CA2588628A1

CA2588628A1 - Devices for air distribution systems

Info

Publication number: CA2588628A1
Application number: CA002588628A
Authority: CA
Original assignee: Venmar Ventilation Inc
Current assignee: Venmar Ventilation Inc
Priority date: 2007-05-15
Filing date: 2007-05-15
Publication date: 2008-11-15
Also published as: WO2008138149A1; US20090029642A1; CA2631280A1

Description

The present invention in an aspect relates to air conditioning systems which include an air ventilation component for delivery of fresh air to an interior space (e.g. of a building). The invention, for example, relates to HVAC systems (i.e. to system that provides heating, ventilating, and/or cooling within or associated with a building) This invention generally relates to the distribution of outside fresh ventilation air into an interior space and/or mixing fresh ventilation air with interior space air. The invention in particular relates to a control set up that may operate an air distribution fan of an air conditioning system (e.g. a fan of a furnace, a fan of a cooler and /or a fan of an air ventilator) independently of the operation of air conditioning elements of the air conditioning system (for example with a furnace element, a cooling element, etc. in lock up mode). The invention more particularly relates to a control set up that may, (with the furnace element, cooling element etc. in lockup mode) activate the air distribution fan (e.g. in response to a timer and/or in response to air temperature such as for example in response to a sensor signal with respect to the temperature of the fresh exterior air and /or stale interior air) and that may operate an outside air damper in an outside air duct of an air conditioning system for the delivery of fresh air to an interior space, in response to air temperature such as for example in response to a sensor signal with respect to the temperature of the fresh exterior air and /or stale interior air.
While the air movement control (ler) will be discussed herein in more detail with respect to a fanless (i.e. passive) air ventilation means, the air movement control (ler) may alternatively be used with an air ventilation means having its own blower component. Thus an air control(ler) may be used in conjunction with the fan of an air conditioning means (or element thereof) where the air ventilation means does not have its own blower means; the air control(ler) may be used with the fan of the air ventilation means if the air ventilation means has its own blower means; and an air control(ler) may be used in conjunction with the fan of an air conditioning means (or element thereof) and the blower means of the air ventilation means when the air ventilation means has its own blower means Air conditioning systems for residential buildings, having heating and/or cooling and/or humidifying and/or dehumidifying and/or air-cleaning modes, for conditioning air, normally operate the system air distribution fan only when the air conditioning system is operating to condition air.
Alternatively, the air distribution fan of an air conditioning system can be operated constantly;
however, such a constant running of the fan would be inefficient.

In air conditioning systems, a heating and/or cooling and/or humidifying and/or dehumidifying and/or air-cleaning apparatus produces conditioned air. Normally, the conditioned air is distributed by a fan or blower through various ducts throughout an interior space in order to place the conditioned air at desirable locations.

Generally, a thermostat and/or humidistat is used to activate the conditioning apparatus. For example, when the air temperature within an interior space drops below a selected level, an air temperature sensor and switch in a thermostat can activate a heating apparatus and an air distribution fan; likewise, when the air temperature within an interior space rises above a selected level, an air temperature sensor and switch in a thermostat can activate a cooling apparatus and an air distribution fan; and in analogous fashion humidity may be like wise controlled.

The conditioning apparatus and air distribution fan are deactivated when the interior space temperature or humidity reaches the selected level.

In some air conditioning systems, while in the heating mode, the air distribution fan may continue to run after the heating apparatus has been deactivated, usually until residual heat in the heating apparatus has been removed by the circulating air. Likewise, in some air conditioning systems, while in the cooling mode, the air distribution fan may continue to run after the cooling apparatus has been deactivated, usually for a preset delay time to continue to distribute cool air while the cooling apparatus is still cold.

The running of the air distribution fan coupled with the introduction (and if desired or necessary the removal of stale air from an interior space to the outside of the interior space) is counter-productive, in that there is an energy penalty related to heated or cooled air being ejected from the interior space.

It would be advantageous to have a control means or setup which could (as desired) limit the delivery of fresh air to the interior of a space to the periods when for example a heating or a cooling apparatus is deactivated , i.e. locked out of heating or cooling mode.

In air conditioning systems, an outside air duct connecting between the outside of an interior space and the return air side of an air distribution fan, for the purpose of drawing in ventilation air, is known. Often, motorized dampers are placed in the outside air duct to limit outside air entry to times when the air distribution fan is operating. Motorized outside air dampers are known and exist commercially. It is known to energize an outside air damper upon energizing an air distribution fan, and it is known to de-energize a damper upon de-energizing an air distribution

2 fan. However, no known control systems exist for (independently) energizing an air distribution fan during non-conditioning mode(s), then for as long as the fan continues to operate, to periodically close and open an outside air damper based in response to air temperature.

The primary objective of the present invention is a fan recycling control system for using the existing air distribution fan and ducts of an air conditioning system, having an air ventilation mode in addition to heating and/or cooling and/or humidifying and/or dehumidifying operating modes, for the periodic distributing of ventilation air and mixing of air throughout the interior air space served by the air conditioning system while the air distribution fan is not operating due to lack of a positive signal from the thermostat or humidistat for heating or cooling or humidifying or dehumidifying or constant fan modes.

The fan recycling control provides a means for operating the air distribution fan, where the last operation of the air distribution fan could have been due to a positive signal from the thermostat or humidistat for heating or cooling or humidifying or dehumidifying or constant fan modes of the air conditioning system, or due to fan operation initiated by the fan recycling control. The present invention includes for example an outside air damper recycling control having a means to open a motorized outside air damper, for the purpose of drawing in ventilation air, each time the air distribution fan operates, and for as long as the air distribution fan continues to operate, having a means to cycle, periodically close then open, the outside air damper based on temperature, and having a means to cause the motorized outside air damper to close at the end of each such operation of the air distribution fan.

The fan recycling control and outside air damper recycling control can be effective on many different types of air conditioning systems. For example, the invention can be equally applied to a cooling only air conditioning system for cooling and dehumidifying, a cooling air conditioning system with electric beat for cooling and dehumidifying and heating, a heat pump air conditioning system for cooling and dehumidifying and heating, a gas or oil furnace system with or without a humidifier for heating and humidifying, and any combination of these systems.

With respect to control in response to temperature such control may be facilitated by the use of temperature sensors, for example, of the thermistor type. The thermistor may for example be located inside the stale air intake (i.e. duct) for monitoring the temperature coming from the air handler such as a furnace or cooling air conditioner (i.e. from the interior of the space) and may transmit the information (i.e. a temperature signal) to the controller. With this information the controller will be able to determine when the air handler is in cooling or heating mode A thermistor

3 may also be placed inside the fresh air intake (duct) for monitoring the temperature coming from outside the space and may likewise transmit the information to the controller.
The controller according to his programation will decide when it is appropriate to ventilate and when it is not.
Based on the information received by the thermistors the controller may also be able to decide when it is appropriate to defrost the energy or heat recovery core. The controller will further be suitable configured (i.e. programmed in case of a programmable controller) to ensure that, as long as it is possible, the periods of ventilation and/or defrosting are outside the cooling and heating periods and also the minimum ventilation time is achieved. -The controller is programmed by the installer or the user to provide the correct amount of ventilation to the house. This could be done by two different ways. First by entering the amount of CFM required by the building code and the amount of CFM that the unit is capable of (measured by the installer). This will give the percentage of ventilation time that we will have. The second way is to enter directly the percentage of ventilation that the unit will work.

4 Inventive statement paragraphs:, i.e. the present invention particularly relates to :

1. An outside air damper recycling control for an air conditioning system, comprising:

- an air conditioning system having a fan to distribute conditioned air to or in an interior space and if desired or necessary to discharge (stale) air from said air space;

- a damper for connecting and disconnecting outside air to the interior space;
and - a recycle control means for controlling the damper in response to temperature of air inside said interior space and/or air outside said interior space (i.e. outside ambient fresh air) - (e.g. in response to one or more (periodic) air temperature signal(s) generated with respect thereto ).
2. The recycling control of paragraph 1, further comprising:

means for controlling both the air conditioning system and/or the fan.

3. The recycling control of paragraph 2, wherein said recycle means additionally controls the operation of said fan in response to temperature [ for example, . of air inside said interior space and/or air outside said interior space (i.e. outside ambient fresh air) ]
(e.g. in response to one or more (periodic) air temperature signal(s) generated with respect thereto ).

4. The recycling control of any one of paragraphs 1 to 3, wherein the air conditioning system comprises air ventilation means, said air ventilation means being configured for at least one of the following air treatments, namely - in general, the delivery of fresh air to said interior space (with or without exchange of stale interior air for fresh interior air, with or without moisture exchange between stale interior air for fresh interior air and with or without (sensible) heat exchange between stale interior air for fresh interior air);
- in particular, the exchange of air between the interior and exterior of said interior space;
- in particular, the transfer of water moisture between exhaust air taken from said interior space and fresh air taken from the exterior ambient air; and - in particular, the transfer of sensible heat between exhaust air taken from said interior space and fresh air taken from the exterior ambient air.

5 5. The recycling control of paragraph 4, wherein the air conditioning system further includes at least one air conditioning means selected from the group consisting of - an air cooling means, - an air heating means, - an air humidifying means, - an air dehumidifying means, and - an air cleaning means (e.g. air filter means).

6. The recycling control of any one of paragraphs 1 to 5, wherein the damper includes:
a motorized control to open and close the damper.

7. The recycling control of any one of paragraphs 1 to 6, wherein the air conditioning system is a central air conditioning system.

7a. The recycle control of any one of paragraphs 1 to 7 wherein the air conditioning system comprises air ventilation means which includes a ventilation fan or blower element (e.g. a stale and/or fresh air blower(s)).

8. A method of mixing air in an interior space with air from outside the interior space when not conditioning the air by one or more air conditioning elements of an air conditioning system(in particular when not conditioning air with for an air cooling means or an air heating means), the system having an air conditioning component comprising a fan and one or more air conditioning elements, the system further comprising an air ventilation component having an outside air damper for opening the interior space to outside air, comprising the steps of:

deactivating air conditioning mode or modes of said one or more air conditioning elements (in particular deactivating any air cooling means or any air heating means as the case may be), activating the fan (if not already activated) and activating an outside air damper in response to a temperature signal from a temperature sensor [ ]; and periodically closing and opening the damper dependent the operating time of the fan and/or or in response to temperature of air inside said interior space and/or air outside said interior space (i.e. outside ambient fresh air) - (e.g. in response to one or more (periodic) air temperature signal(s) generated with respect thereto )

9. The method of paragraph 8 further includes:

selecting the temperatures for opening and closing of the damper.

10. The method of paragraphs 8 or paragraph 9, wherein the air ventilation component comprises air ventilation means, said air ventilation means being configured for at least one of the following air treatments, namely - in general, the delivery of fresh air to said interior space [ a)with or without exchange of stale interior air for fresh interior air, b) with or without moisture exchange between stale interior air for fresh interior air and c) with or without (sensible) heat exchange between stale interior air for fresh interior air];
- in particular, the exchange of air between the interior and exterior of said interior space;
- in particular, the transfer of water moisture between exhaust air taken from said interior space and fresh air taken from the exterior ambient air; and - in particular, the transfer of sensible heat between exhaust air taken from said interior space and fresh air taken from the exterior ambient air.

11. The method of paragraph 4, wherein said one or more air conditioning elements are selected from the group consisting of:

- an air cooling means, - an air heating means, - an air humidifying means, - an air dehumidifying means, and - an air cleaning means.

11 a. The method of any one of paragraphs 8 to 11 wherein the air conditioning system comprises air ventilation means which includes a ventilation fan or blower element (e.g.
a stale and/or fresh air blower(s)).

12. An air movement control(ler) for an air conditioning system, the air movement control comprising a fan recycling control and an outside air damper recycling control, the air conditioning system comprising an air conditioning component comprising a fan and one or more air conditioning elements, the air conditioning system further comprising an air ventilation component and air damper means:

the air conditioning component comprising a fan to distribute conditioned air in or to an interior space and if desired or necessary to discharge (stale) air from said air space, the air conditioning component comprising one or more elements selected from the group consisting of - a cooling apparatus, - a heating apparatus, - a humidifying apparatus, - a dehumidifying apparatus, and an air cleaning apparatus;

the air ventilation component comprising an air damper means, said air ventilation component being configured for at least one of the following air treatments, , namely - in general, the delivery of fresh air to said interior space [ a)with or without exchange of stale interior air for fresh interior air, b) with or without moisture exchange between stale interior air for fresh interior air and c) with or without (sensible) heat exchange between stale interior air for fresh interior air];
- in particular, the exchange of air between the interior and exterior of said interior space;
- in particular, the transfer of water moisture between exhaust air taken from said interior space and fresh air taken from the exterior ambient air; and - in particular, the transfer of sensible heat between exhaust air taken from said interior space and fresh air taken from the exterior ambient air said air ventilation component further comprising an outside air duct connecting outside of a building to said fan and if desired or necessary an inside air duct connecting inside of a building to said fan;

said air damper means comprising an outside air damper in the outside air duct; and if desired or necessary an inside air damper in the inside air duct the air movement control comprising a thermostat and/or humidistat for activating and deactivating said air conditioning elements and the fan;

the fan recycling control means being configured to periodically activate and deactivate only said fan in said air conditioning system in response to a (predetermined) temperature signal when not conditioning the air by said one or more air conditioning elements (in particular when deactivating any air cooling means or any air heating means as the case may be), and the outside/inside air damper recycling control being configured to open the outside and/or inside air damper each time the fan begins to operate in response to the fan recycle control means, and for as long as said fan continues to so operate, cycles, periodically closes and opens, the outside air damper (and as desired or necessary the inside air damper) based the temperature signal.
14. The air movement control (ler) of any one of paragraphs 8 to 11 wherein the air conditioning system comprises air ventilation means which includes a ventilation fan or blower element (e.g. a stale and/or fresh air blower(s)).

The following will discuss in more in more detail example embodiment(s) of the present invention and in particular embodiment(s) where the air ventilation means is passive (i.e. the air ventilation means has no fan or blower means for inducing air movement).

Various systems and apparatus as well as devices and structures which may be used in the context of the present invention to deliver fresh air to an interior space (e.g. to exchange indoor air with outdoor air). The air exchange with outdoor air may be exploited in conjunction with air handling systems (e.g. (air) of a forced-air HVAC system type for the conditioning (e.g. heating, cooling) of air in an enclosure such as a building, a room of a structure such as a residence, and the like.

Such systems (e.g. ventilation apparatus or systems) may for example include a blower element to move air for the air exchange taken from inside an enclosure e.g. a building to outdoor air and to drawn into the enclosure e.g. building air from outdoor. It may also for example include an element for the transfer of heat and or humidity from conditioned exhaust air (taken from inside an enclosure e.g. a building) to exterior fresh air (drawn into the enclosure e.g. building).
Exchanging air with outdoor during conditioning (e.g. heating, cooling) of air by the forced-air HVAC system in an enclosure such as a building, a room of a structure such as a residence, and the like may be detrimental to forced-air HVAC system efficiency.

The present invention relates to a controller that optimizes air exchange with outdoor from and to a forced-air HVAC system. The controller is monitoring the forced-air HVAC
system activity and adjusts the air exchange with outdoor accordingly. If any adverse condition are present, the air exchange with outdoor is suspended during the adverse condition.

In the following, reference will be made to figures 1 to 7 wherein the reference numerals refer to elements which have are described in the legend found below with respect to figures 1 to 7.

Supply - 16 3 01- = =

Heating / Cooling Unit 4 Air Exchanger Forced-air HVAC SYSTEM
11 Heating / Cooling Unit 14 ~ '. . 13 1 f- O
tL
-----O
~ 19 Humidity controller Return 1 7 El 18 Thermostat 10 -Figure 1 (Referring to Figure 1). As an example, a passive air exchanger 1 is shown which is provided with a heat exchanger core 4 (i.e. an air-to-air sensible heat exchanger core and/or a desiccant exchanger core (i.e. both types of cores may be present for transfer of water moisture and sensible heat) to execute exchange between fresh airflow path from outdoor to indoor 11 and the 10 stale airflow path from indoor to outdoor 12. The exchanger 1 is a passive exchanger in that it does not have blower means for inducing movement of air through the air ventilation means (i.e.
air movement through the exchanger 1 is induced by the blower or fan of the air conditioner (i.e.
the fan of the furnace, etc.) . The efficiency of the heat exchanger or desiccant exchanger may vary. In some applications the air-to-air exchanger core 4 may be replaced by a bypass 15 apparatus that does not transfer water moisture or sensible heat between the fresh airflow 11 and the stale airflow 12. In that instance there is a direct air exchange with-outdoor. This may be desirable where climatic conditions are favorable for an extended period of time. The same air exchanger 1 could as may be understood from herein alternatively have its own self contained air moving capacity such as blowers.

(Referring to Figure 1, 2). The mechanical work required to move air through the air exchanger 1 is created by the heating I cooling unit fan 14 the heat / cool exchanger 15 and the duct work inside the dwelling 16, 17. The air supply 33 of the heating / cooling unit builds a positive air static pressure of around 0.3" (w.g.). The air return of the system 34 builds a negative air static pressure of 0.1" (w.g.) maximum. This pressure differential is used to exchange air with outside the dwelling. In some instances, air inlet/outlet are controlled by a humidity controller 21. In that case, air inlet/outlet are opened or closed depending of the humidity controller set point.
(Referring to Figure 2). A portion of the heating /cooling supply airflow 33 is diverted through 12 and passed through a sensible heat exchanger or desiccant exchanger 4 to execute exchange with fresh airflow path from outside to inside 11, 11a prior being exhausted directly 12a.
(Referring to Figure 2 - a known type pf configuration). The fresh airflow from outdoor to indoor 11 is passed through a air filtering media/apparatus 5 then through a sensible heat exchanger or desiccant exchanger 4 to execute exchange with stale airflow path from indoor to outdoor 12, 12a prior being fed to mix with the return air, 11 a , 34 of the heating / cooling unit.

rll 3 - ------------- ; ............_........ ~ 12..-1 32 I11a ~
_..._......... ~.......... , , =---------- ---------~--- --------~ 14 12a 2 12a " 1 - -- i ---+------34 ~--Figure 2 (Referring to Figure 1, 2, 3). The draw-back of this air exchanger unit is that the total energy efficiency in cold or warm climate is almost null over a long period a time.
This is due to the fact that the unit 1, 38 is exchanging air mainly when the Heating / Cooling Unit Fan 14, 35, 36 is running. This means that the air exchange occurs during the heating or cooling process. These results in an energy penalty as a portion of the air treated for heating /
cooling by the exchanger 15 is being exhausted to outdoor atmosphere (see figure 3 for the penalty zone. This treated air 33 has a heat / energy content different than normal ambient air in the dwelling.

Heating / Cooling 1.11 phase Thermostat Call for heat or cool <<1 ----------- t. - ----------------35 f " ' '- '" '-"'-"' ~ Post Heating / Cooling . ~~
Fan cycle Fan of Heating / CooGng unit ---------------------- ~. ..............................__ .................36 Heat or cool cvcle::: =
.......
~.__~.'~_:_'i':~t . . . . . . . . . . . . . .... .:<' '::.;
EXHA
UST&FRESHAIR
Air ;nlet and outlet 37 ::i::
>::: : ::: : :>
TOTAL ENERGY PENALPY ZONE~
~...:::
E_ ........ .
Maximum Minimum Energy penalty zone Energy penalty zone AIR EXCHANGE -....:::::::::
$ 38 .. .......... . ::,,:
ti m e ------------------>
Figure 3 (Referring to Figure 4). The present invention seeks to attenuate this shortfall (i.e. energy penalty), by controlling, with air-to-air exchanger control 22, (in response to temperature) the fresh air inlet damper/stale air outlet damper so as to essentially restrict delivery of fresh air during periods when for example the furnace/cooler is in lock down. This type of control system may be configured in any (suitable) manner to avoid exchanging inside air with outside air when it is less recommendable to do so (i.e. to avoid the energy penalty zone). In order to do so the air-to-air exchanger control may be configured in any (suitable) manner so as to be able to sense and control the Heating / Cooling Unit Fan upon specific request complementary (e.g.
independent) to the Heating / Cooling Unit thermostat.

13 Supply - 16 Heating/ Cooling Unit - 4 24,25,26 Air Exchanger S1 Forced-air HVAC SYSTEM

11 39 -- - - Heating/ Cooling Unit 14 kr 12 27,28,29 O
= -,' ' D

I ! ' <: , o ~

~ -- 10 31 Return 17 68 v 18 - Thermostat Figure 4 (Referring to Figure 4). The first step is to monitor the status of the Heating / Cooling Unit. In a 10 standard residential HVAC system, the thermostat 18 controls the Heating /
Cooling Unit 13. The thermostat provides the necessary control signals for Heating, Cooling and Fan control 19, 20.
Therefore monitoring the thermostat activity enables the air-to-air exchanger control to react accordingly.

15 (Referring to Figure 4). The second step is to enable the air-to-air exchanger control 22 to be able to activate the Heating / Cooling Unit Fan outside the normal Heating /
Cooling phases.
(Referring to Figure 4). The third step, the air-to-air exchanger control 22 may enhance the air exchange strategy upon an external trigger such as for example: Timed Based Functions. The 20 optimized air-to-air exchanger control uses various Time Based Schemes to regulate and/or

14 optimize air exchange accordingly.

However, in accordance with the present invention the air to air exchanger control 22 is configured to respond to temperature for controlling the air dampers 2 and 3 of the air ventilation unit. Outdoor / Indoor climatic Sensors 24, 25, 26, 27, 28, 29. The air-to-air exchanger control may use one or more sensors to monitor temperature to regulate air exchange;
on the other hand, other environmental parameters may as desired or necessary be used in addition to temperature or even in place thereof (such as humidity, gaseous pollutant or particles) to regulate air exchange accordingly.
The detection of Air Moving Devices in the dwelling is determined by 30, 31.
The air-to-air exchanger control may be configured to detect the activity of additional Air Moving Devices such as bathroom fans, range-hoods, cloth dryers or fans.

(Referring to Figure 4a). this figure schematically shows in graphic form similar to figure 3 the avoidance to the energy penalty shown in figure 3. When the thermostat call for heat or cool it send a signal (1) to the furnace or air handler to start its fan (2). The controller of the present invention will know by the thermistor inside the stale air intake port that cooling or heating mode is in progress (i.e. due to temperature signal level) and it will make sure the dampers will be closed.
When the cooling or heating time will be finished (i.e. detected by the lower or higher temperature signal as the case may be) , the controller system is suitably configured to ask the furnace or air handler blower to continue to run (extended fan call) for a determined period of time (Td) to ensure ventilation in the most energy effective period. In the mean time the controller system will open his damper (3).

Extended fan call k _:: :
_ _ _ _ - , - - - - - - ~Xdjustable extended Fan call Therniostat 4 ~
Call for heat or cool ;---------- ( I-- - ----------------IA

------------------------------------- --r---------------------=
, , . .
Air Hemdljr k . . . . . . . Td , .
FAN II' ------------------- .. :.....

2A 1"at~noc?i1~- lr EXHAUST!&SUPPLY k .

DAMPERS CONtROL k r._ . . . . . . . . . .
f sA k A
k. : : ;J ........:..:..::
AIR EXCHANr~E ;
r:

Time ------------------------->
Figure 4a (extended fan call) IA : heating or cooling call 2A : Air handler fan 3A : Damper activation 4A : Ventilation period In particular, when the thermostat calls for heat or cool it sends a signal (1A) to the furnace or air handler to start its fan (2A). The controller will know by the termistor inside the stale air intake port that we are in cooling or heating mode and it will make sure the dampers will be closed. When the cooling or heating time will be finished, the controller system will ask the furnace or air handler blower to continue to run (extended fan call) for a determined period of time (Td) to ensure ventilation in the most energy effective period. In the mean time the controller will open his damper (3A).

(Referring to Figure 5). The air-to-air exchanger control 22 can be a stand-alone device or embedded into various systems and apparatus as well as devices and structures which may be used or to exchange air with outdoor. The thermostat to HVAC forced-air system signal arbiter (TSA) 51 monitors the operating conditions of the forced-air HVAC system.

Optimized Air-to-Air Exchanger Controller for Forced-Air HVAC Systems ., ..
________1 ,_________---------- ____-____----------OUTDOOR AIR-EXC:HANGER OUTDOOR / INDCX7R i AIR MOVING DEVICES
AIR INLE'T / OUTLET BLOWER i BNVIRONMEN'1'AL i ~ DE1'ECTION
CONTROL CON'1'ROI. SE:NSORS CON'1ROL
--------~-r-----------------~.-_-- ------f_.._ -------------- ' i r_ ~s F CPU

-'-, THERMOSTAT to HVAC FORCED-AIR SYSTEM END-USER
SIGNAL ARBITER VENTILATION
TSA REMOTE CONTROL
' ;' : -----------------------O
2C OG RH Wl Yl O RC O =88 : O O O O O O 01 Standard inodule 22 Optional inodule - - - - - -Figure 5 The Thermostat Signal Arbiter (TSA) monitors:
1. Heating activity, 2. Cooling activity and 3. HVAC system Fan activity.

The TSA 51 can control the HVAC system Fan independently from the HVAC SYSTEM
thermostat 18 outside a heating or a cooling call by the thermostat.
The HVAC thermostat connects to the input 52 of the TSA and the TSA output 53 is connected to the HVAC system thermostat terminals.

The microcontroller ( CPU ) 52, provides the necessary combination of electronic components to ensure the functionality of the system.

The outdoor inlet /outlet control module 54, provides the necessary means to control air openings with outdoor. It can provide ON/OFF signals or a more sophisticated control as a proportional aperture control for example.
The optional blower control 55 can be used to control air-to-air exchange blower that could be added to increase the air flows with outside 11, 12.

The optional indoor/outdoor environmental sensors 56 can monitor a single or any combination thereof:

1. Outdoor temperature 2. Outdoor relative humidity 3. Outdoor gaseous pollutant 4. Indoor temperature 5. Indoor relative humidity 6. Indoor gaseous pollutant The air exchange with outside can therefore be based on levels of environmental conditions as stated above.

In addition there are various air exchange strategy based on the operating conditions of the Heating / Cooling Unit activity and time based related functions.

The optional air moving devices detection and control module 57 can be used to implanted alternate ventilation strategies by the detection and or control of air moving devices inside the dwelling 30, 31.

Defrost mode (Referring to Figure 6, 7). During cold weather, prior to expelling the relatively warm exhaust air, the equipment provides for the transfer of heat from the relatively warm exhaust air to the relatively cool (fresh) outside air by the use of a suitable heat exchange element. However, since the warm interior air will usually contain a certain amount of moisture, the cooling of the interior air can result in the formation not only of water but of ice if the exterior air is below the freezing point of water. An uncontrolled buildup of ice on the exhaust air side of the system can result in decreased heat transfer, and even outright blockage of the exhaust air path.
Accordingly a means of periodically defrosting such a system is a requirement in order to maintain its efficiency. Thus, the present invention provides also a defrostable ventilation method, for exchanging air between the interior and exterior of a building, for transferring heat from exhaust air taken from the building 12a, 12b to fresh air 11 taken from the exterior ambient air for delivery to the building, and wherein air from the interior of the building is used as defrost air to defrost the air exchanger as the fresh and stale air Air inlet/outlet in defrost position 37c. The defrost cycle is independent of the heating / cooling unit status 35 as no air is being exchange with outdoor thus avoiding an energy penalty.

f........ - 13 ----- _ ... ~..._ ............. _ _. .

12b ~- ~ 11a ~ ... . ._ .t .............. . --------- ------------------------' 14 12a 1 j ---~------' 34 -~-Figure 6 -----------~
Thermostat Call for heat or cool 1 t ~
---------- ' +----- ----------------35 ~....
l I
Maximum ~-=~---~-: TOTAL ENERGY PENAI t LONE Fe gy penalty one Energy penalty zone . . . -.--~-- -- --~,-,=,,- -~ ~':':':':':':':':'~ ~:4 =
FanofHeaHng/Coolingi .~.~.~.~~~~~~~~'~' I +J+
, , , , =''''''''~'~'~'~'' unit , . , = ;~'~'~'~: : ~
......:..
_---.: L ....: L _--_ ~.... . ..:..: . . . ..
Heat or cool cycle-: .

:::::::::::~:~:~:~:~:~:~:~:~r~
...
EXHAUSTAIR ~~i~i~i~i~~~~~~~~~~~~~i~~~i~~~~~i~i~. ~:~:~.
~:~:~:.~iiiiiiii:i~i~>i~:~~ 37c outlet ::::.. ii~:~:~:~:~~:~:~:~:~:...:.
...::>ii::
i 37a FRESH AIR
inlet ::.:.:...... . . :.:.f:..:.>:. a ..
:....:.....
I ~ ~ Defrost cycle I
3 ~
AIR EXCHANGE

ti m e ------------------>

Figure 7 Legend for Figures 1 to 7 Reference Description 1 Heating / Cooling Unit Air Exchanger 2 Exhaust air outlet damper 3 Fresh air outlet damper 4 Air-to-air Heat / Energy recovery medium Air exchanger air filtering media/apparatus 6 Dwelling exterior wall 7 Fresh air duct from outdoor 8 Stale air duct to outdoor 9 Stale air duct from dwelling treated air supply Fresh air duct to dwelling air return 11 Fresh air from outdoor to dwelling 11 a Fresh air from outdoor to dwelling with differential heat and/or moisture.
12 Stale air to outdoor from dwelling 12a Stale air to outdoor from dwelling with differential heat and/or moisture.
12b Stale air bypass for defrost 13 Heating /Cooling unit 14 Fan of Heating / Cooling unit Heat / Cool exchanger 16 Heating / Cooling Supply air duct 17 Heating / Cooling Return air duct 18 HVAC Thermostat 19 HVAC Thermostat wiring HVAC Air Handler controller terminal block 21 Humidity controller (Humidistat or De-Humidistat 22 Optimized Air Exchanger Controller 23 Optimized Air Exchanger Controller wiring to HVAC Air Handler controller terminal block 24 Outdoor temperature sensor Outdoor humidity sensor 26 Outdoor gas sensor (CO2, VOC, CO) 27 Indoor temperature sensor 28 lntdoor humidity sensor 29 Intdoor gas sensor (CO2, VOC, CO) Air moving devices 31 Air moving devices detection 32 Heating Cooling unit Air filtering media/apparatus 33 Supply air distribution to dwelling 34 Return air distribution from dwelling 35 Thermostat call for heat or cool 36 Fan of Heating / Cooling unit 37 Air exchanger fresh and stale air inlet and outlet 37a Air exchanger exhaust air outlet only 37b Air exchanger fresh air inlet only 37c Fresh and stale air inlet / outlet in defrost position 38 Air exchange between indoor and outdoor 39 Stale air blower (optional) 40 Fresh air blower (optional) 50 CPU or Logic unit 51 Thermostat / HVAC forced-air system signal arbiter (TSA) 52 Thermostat to Air Exchange controller terminal blocks 53 Air Exchange controller to HVAC forced-air system terminal blocks 54 Outdoor air inlet / outlet control 55 Air exchanger blower control (optional) 56 Outdoor / indoor environmental sensor interface (optional) 57 Air moving devices detection and control (optional) 58 & 59 End user ventilation remote control interface The present invention in another aspect relates to a damper assembly (e.g. for an air ventilation apparatus). The present invention in particular relates to a damper assembly exploiting a crankshaft to induce displacement of damper means comprising two or more damper elements from one position to another. The present invention further relates to a damper assembly exploiting a damper (electric) motor the shaft of which rotates in a single rotational direction (i.e.
the motor is not reversible). The damper assembly will be described herein by way of example only in relation to an example ventilation apparatus but may of course be exploited in other contexts.
The present invention additionally relates to a damper assembly which may as desired or necessary exploit a sensor means for detecting the position of a damper e.g.
in relation to its predetermined correct open and closed states (e.g. damper motor off) including maximum open state as well as jammed open or jammed closed states (for more specific details of the structure of a damper position detection means please see US patent application no.
11/195697 published July 13, 2006 under no 20060151736 the entire contents of which are incorporated herein by reference).

Inventive statement paragraphs with respect to a damper assembly: i.e. the present aspect of the invention particularly relates to:

1. A damper assembly, comprising:

a support means defining a first opening (e.g. stale air inlet opening), a second opening (e.g.
fresh air outlet opening) and a third opening (e.g. defrost (stale) air recycle opening);

a first (e.g. stale air recycle) damper element and a second (fresh air) damper element, each of said damper elements comprising a respective connector element, said first damper element being displaceable between a respective first position wherein the first damper element closes off said third opening and the first opening is unobstructed by said first damper and a respective second position wherein the first damper element closes off the first opening and the third opening is unobstructed by said first damper element, said second damper element being displaceable between a respective first position wherein the second opening is unobstructed by said second damper and a respective second position wherein the second damper element closes off said second opening, (i.e. each damper element being pivotally mounted or connected to said support means) a displacement component for displacing said damper elements between said respective first position and said respective second position said displacement component comprising - a damper displacement element comprising a crankshaft component having a first and a second interconnect element (i.e. the crankshaft being pivotally mounted or connected to said support means) and - first and second push-pull (e.g. stiff elongated) damper connection elements (e.g. stiff spring), said first push-pull damper connection element being connected to the connector element of said first damper element and to the first interconnect element of said crankshaft component, said second push-pull damper connection element being connected to the connector element of said second damper element and to the second interconnect element of said crankshaft component, wherein said crankshaft component is configured such that each of said damper elements is coupled to said crankshaft means such that a complete rotation of said crankshaft means in a single direction is able to induce displacement of said first and second damper elements from said respective first position thereof to said respective second position thereof.
2. A damper assembly as defined in paragraph 1 wherein assembly said includes a (electric) motor having a shaft coupled to said crankshaft component for rotation of the crankshaft component by the motor shaft.

3. A damper assembly as defined in paragraph 2 wherein said motor provides a rotational force in a single direction.

4. A damper assembly as defined in paragraph 1, 2 or 3 further comprising damper position detection means comprising a first detection portion fixed to the support means and a second detection portion fixed to the crankshaft means, said damper position detection means being configured for detection of the disposition of the damper means in relation to its open and closed states including maximum open state, intermediate open states and jammed open and jammed closed states. (For more specific details of the structure of damper position detection means please see US patent application no. 11/195697 published July 13, 2006 under no 20060151736 the entire contents of which are incorporated herein by reference).

Figure 8 is a schematic perspective view of a ventilation apparatus in accordance with the present invention, the ventilation apparatus comprising, inter alia, a housing provided with punch out portions (on opposite sides thereof as well as the top thereof) for the provision of a fourth (stale air) inlet opening as well as an example embodiment of a motorized damper assembly in accordance with the present invention as shown in figure 16;

Figure 9 is a side view of the ventilation apparatus shown in figure 8 showing a side punch out portion for the provision of a side fourth inlet opening, the opposite side of the apparatus having similarly disposed side punch out portion;

Figure 10 is a top view of the ventilation apparatus shown in figure 8 showing a top punch out portion for the provision of a top fourth inlet opening;

Figure 11 is a sectional view along A-A in figure 10 showing the example embodiment of the motorized damper assembly of figure 16 in the area designated as Detail A;

Figure 12 shows in enlarged view the Detail A of figure 11;

Figure 13 is a perspective of the ventilation apparatus of figure 1 wherein the outer housing element is cut away to expose the interior of the ventilation apparatus , the heat exchange core also being removed, and the example embodiment of the motorized damper assembly of figure 16 in the area designated as Detail B;

Figure 14 shows in enlarged view the Detail B of figure 13;

Figure 15 is a perspective from the opposite side of the ventilation apparatus as shown in figure 13 wherein the outer housing element is cut away to expose the interior of the ventilation apparatus , the heat exchange core also being removed, FIG. 16 is an exploded perspective view of the example embodiment of a motorized damper assembly in accordance with the present invention as shown in previous figures 11 to 15, the damper assembly being provided with a crankshaft means and a two component damper coupling means;
Figure 17 is a schematic side view of the ventilation apparatus of figure 1 with the example embodiment of the motorized damper assembly of figure 16 shown in solid line while the rest of the apparatus is shown in dotted line outline, the apparatus dampers being in open air exchange position;

Figure 18 is a schematic fresh air in side view of the ventilation apparatus of figure 1 with the example embodiment of the motorized damper assembly of figure 16 shown in solid line while the rest of the apparatus is shown in dotted line outline, the apparatus dampers being in open air exchange position;

Figure 19 is a schematic side view of the ventilation apparatus of figure 1 with the example embodiment of the motorized damper assembly of figure 16 shown in solid line while the rest of the apparatus is shown in dotted line outline, the apparatus dampers being in closed air recirculation (i.e. defrost) position;

Figure 20 is a schematic fresh air in side view of the ventilation apparatus of figure 1 with the example embodiment of the motorized damper assembly of figure 16 shown in solid line while the rest of the apparatus is shown in dotted line outline, the apparatus being in closed air recirculation (i.e. defrost) position;

Turning first to figure 16 the various reference numbers with respect to the illustrated example embodiment of a motorized damper assembly in accordance with the present invention are set forth in the following legend and will be used throughout the figures 8 to 20 as common elements:
REFERENCE nos. FIGURE 16 DESCRIPTION

14 DEFROST DAMPER Bushing and seal 13 (FRESH) AIR SPRING
12 (DEFROST) SPRING

15 DAMPER CAM SUPPORT

16 COVER DAMPER-MOTOR

17 DAMPER CAM CONNECTOR

Figures 8, 9 and 10 show the exterior form of the housing for the ventilation apparatus 20. The housing has three openings, indicated generally as 21 a, 21b and 21c. The ventilation apparatus comprises punch (or cut) out portions (on opposite sides thereof as well as the top thereof) the top punch out and one side punch out being indicated by the reference numerals 22, and 24.
These punch out areas have weakened borders to facilitate the removal a respective part of the housing wall (including interior insulation, if present) so as to provide an opening for use as a fourth (i.e. fresh air) outlet or opening for the ventilation apparatus. The weakness of a punch out portion my be provided in any suitable (known) manner (e.g. by scoring the outer metal) for the provision of a fourth (fresh air) inlet opening as well as an example embodiment of a motorized damper assembly in accordance with the present invention as shown in figure 16.
The choice of which punch out (i.e. top or side) to remove is left to the installer. Once the punch out is removed then stale( interior) air and fresh (exterior) air may for example be caused to flow through the ventilation apparatus as seen in figures 9 and 11 depending on the position of the dampers 3 and 14. Figure 22 (below) illustrates housing with a side punch out removed (and a circular duct ring engaged with the resulting opening. As may be seen in figure 11 a heat exchanger core 28 is disposed in the apparatus in known manner so as to define two separate air flow paths (see for example US patent no. 6209622 and 6855050 the entire contents of which are incorporated herein by reference). In the fresh air mode (i.e. the third opening 29 closed) air may, for example, be forced through the apparatus by the fan of the furnace as set forth with respect to figures 1 to 7; similarly in the recycle mode recourse may be had to the furnace blower to force air through both sides of the exchanger core..

Figure 11 is a sectional view along A-A in figure 10 showing the example embodiment of the motorized damper assembly of figure 16 in the area designated as Detail A. As shown the damper 11 is closing of a first opening (e.g. stale air inlet opening), the damper 3 is closing off a second opening (e.g. fresh air outlet opening) and a third opening 29 (e.g.
defrost (stale) air recycle opening) is unobstructed by the damper 11; i.e. the system as shown in this figure is set for defrost mode whereby warm stale interior air is passed through both air paths of the core 28.
As may be seen the openings are disposed in a T like fashion with the third opening being associated with the stalk of the T while the first and second opening are associated with a respective laterally extending arm of the T. It is to be noted that the foot of the stalk engages a corner edge of the core 28. This 3 component type opening configuration advantageously lends itself to the making of a compact ventilation apparatus which on the one hand allows for the passage of fresh and stale air through the core in respective separate air paths and on the other for the passage of warm stale air through both air paths of the core 28. . The dampers 3 and 11 are pivotally connected to the housing structure (e.g. support) of the apparatus. The damper 11 is pivotally connected at 30 (e.g. in the manner of a door hinge) whereas damper 3 has pivot pins 34 and 35 (figure 16) which rotatably engage suitable openings.

Referring to figures 12, 14 and 16, Figure 12 shows in enlarged view the Detail A of figure 11 and Figure 14 shows in enlarged view the Detail B of figure 13. As may be seen the dampers have attachment elements to which one end of a respective spring 12 or 13 is attached whereas the other end of the springs 12 and 13 is attached to the damper cam; the damper cam is configured such that the springs 12 13 may be attached thereto so that the damper cam may induce displacement of the springs 12 and 13 in a manner analogous to the displacement of pistons attached to a crankshaft of an internal combustion motor. Thus damper movement is effected by the damper cam 8 which as it turns it induces the (stiff) springs 12 and 13 to either respectively push out or pull in such that the dampers 11 and 13 are displaced accordingly.
The damper displacement is induced by the motor 6 which may be activated and deactivated in any suitable manner so as to achieve the desired blockage of the herein mentioned openings.
The motor 6 may for example be associated with a damper position detection means as disclosed in US
patent application no. 11/195697 published July 13, 2006 under no 20060151736 the entire contents of which are incorporated herein by reference.

Figures 17 and 18 show the dampers with the third opening closed (i.e. fresh is able to pass through the ventilator apparatus. On the other hand is a schematic side view of the ventilation apparatus of figure 1 with the example embodiment of the motorized damper assembly of figure 16 shown in solid line while the rest of the apparatus is shown in dotted line outline, the apparatus dampers being in open air exchange position;

Figure 18 is a schematic fresh air in side view of the ventilation apparatus of figure 1 with the example embodiment of the motorized damper assembly of figure 16 shown in solid line while the rest of the apparatus is shown in dotted line outline, the apparatus dampers being in open air exchange position;

Figure 19 is a schematic side view of the ventilation apparatus of figure 1 with the example embodiment of the motorized damper assembly of figure 16 shown in solid line while the rest of the apparatus is shown in dotted line outline, the apparatus dampers being in closed air recirculation (i.e. defrost) position;

Figure 20 is a schematic fresh air in side view of the ventilation apparatus of figure 1 with the example embodiment of the motorized damper assembly of figure 16 shown in solid line while the rest of the apparatus is shown in dotted line outline, the apparatus being in closed air recirculation (i.e. defrost) position;

In accordance with an additional aspect the invention relates to an (preliminary) attachment mechanism allowing a ventilation device to be directly to the duct work of an air conditioning system (e.g. furnace).
Ventilation devices are known which comprise a frame means (e.g. a housing) and ventilation components mounted to said frame (e.g. within a housing) configured so as to define air paths (e.g. internal air paths) for the exchange of sensible and/or latent heat between exhaust air (e.g.
warm and/or moist air) taken from inside a building or enclosure and exterior fresh air (e.g. cool and/or dry air) which is drawn into the building or enclosure; see for example U.S. patent nos.
5,771,707 and 6,209622.

It would be advantageous to have a ventilation device (such as for example shown in figures 8 to 20) which could be directly mounted to the duct work of an air conditioning system, i.e. to facilitate installation thereof, advantageously by a single installer. The following will in particular by way of example only discuss this attachment aspect in relation to the ventilation device shown in figures 8 to 20.

Generally the present invention relates to a two part (preliminary) attachment mechanism comprising a female component (e.g. opening(s)) and a male component (hook(s)) which are able hookingly engage each other for the attachment of a ventilation device to a support (e.g.
duct work) Thus the present invention provides a ventilation device comprising a frame means (e.g. a housing) and ventilation components mounted to said frame (e.g. within a housing) configured so as to define air paths (e.g. internal air paths) for the exchange of sensible and/or latent heat between exhaust air (e.g. warm and/or moist air) taken from inside a building or enclosure and exterior fresh air (e.g. cool and/or dry air) which is drawn into the building or enclosure, characterized in that said frame means comprises a female engagement element configured for (hookingly) engagement with a male element for attaching the ventilation device to a support (e.g. a ventilation duct), the male element being attached to the support.

In figures 23 to 34 which follow the ventilation apparatus shown is the apparatus of figures 8 to 20. The housing of the apparatus has a plurality of female openings 40 along three sides of the upper part of the apparatus housing for hook engagement with a male engagement element having a plurality of male hook members as described below.

FIGs. 21 and 22 illustrate a ventilation apparatus having female openings 40 and a separate male engagement element 42 (having 3 male elements 42a) as well as a type of additional attachment bracket 46 that may be used to complete the attachment of the ventilation apparatus to a duct support structure. The hook engagement between the male and female elements is also shown.
This type of attachment mechanism facilitates the attachment of the ventilation apparatus whereby the forth opening punched out of the top or side wall of the ventilation device may essentially be directly attached to a duct opening by a ring gasket 55a or 55b or the like (see also elements 55c and 55d in figures 25 and 32), i.e. without the necessity of adding additional duct work. The male engagement element 42 is first attached to the duct work by screws or the like, i.e. through screw attachment openings. The additional attachment bracket(s) 46 is (are) likewise so attached to the ventilation apparatus housing. See figure 21 for screw attachment of element 46 thereafter the ventilation apparatus may be attached to a duct work 50 as shown in the various positions and configurations illustrated in figures 23 to 33.

The present invention also relates to a further aspect of an air ventilation apparatus namely water pan for collecting water produced by an air ventilation apparatus through condensation from air;
the pan may a pair of sloped floors sloping downwardly toward each other and may have a water collection groove at the end at least one of the floor surfaces.
Figures 35 to 39 relate to this aspect and by way of example illustrate this aspect of the invention in relation to the ventilation apparatus shown in Figures 8-20.

Figure 35 illustrates an exploded perspective view of various example components of the multi-component housing structure for a ventilation apparatus as shown in figures 8-20 and in particular a water drip pan 70;

Figure 36 is side view of the water drip pan 70 shown in figure 35;

Figure 37 is a perspective side view of the water drip pan 70 shown in figure 35;

Figure 36 is side longitudinal cross-section view of the water drip pan 70 shown in figure 35; and Figure 36 is top view of the water drip pan 70 shown in figure 35 showing the pan interior floor.
As may be seen from figure 38, the water drip pan 70 has a support member indicated generally by the reference numeral 75 for engagement of a corner edge of the heat exchange core 28. As may be surmised the core 28 is maintained in the water drip pan such that the core sides defining the core edge, slope downwardly towards the support member 75. The water pan floors on either side of the support member 75 likewise each possess a surface also sloping downwardly (i.e. inwardly) towards the support member 75 from sidewalls 77 and 79. A
water collection groove is also provided, i.e. to one side of the support member. The support member is broken by (three) channel grooves for allowing liquid communicating with the water collection groove slope from the other side of the support member 75; if desired or necessary these grooves may include a sponge plug. The pan is also provided with a water discharge drain opening communicating with the containment groove plugged by a removable screw plug 80.