US20200370776A1

US20200370776A1 - Dynamic misting control for outdoor condensers

Info

Publication number: US20200370776A1
Application number: US16/883,569
Authority: US
Inventors: Maurice A. Ramirez; Michael V. Bivins; Jonathan Carson
Original assignee: Natural Air E-Controls LLC
Current assignee: Natural Air E-Controls LLC
Priority date: 2019-05-24
Filing date: 2020-05-26
Publication date: 2020-11-26
Also published as: US20200393152A1

Abstract

A dynamic misting control system can supply water to a condenser coil in varying degrees. The control system can include a controller, flow regulator (e.g., pump or separate), and mist generator (e.g., spray nozzles or otherwise). The controller can read outdoor humidity and temperature and vary power to the pump accordingly. The controller can also compare temperatures of the condenser coil to the outdoor humidity and temperature in adjusting the voltage. This can include calculating a voltage based on a first temperature of a coolant supply line and a second temperature in a return line and comparing those temperatures to the outside temperature and humidity.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

This non-provisional application claims priority to provisional application No. 62/852,967, titled “Adaptive, Responsive, Dynamic Building Ventilation Control and Equipment Monitor,” filed May 24, 2019, and also claims priority to provisional application No. 62/852,968, titled “HVAC Compressor and Heat Pump Monitoring System with Misting System for Condenser Coils,” filed May 24, 2019, both of which are incorporated by reference in their entireties.

BACKGROUND

Energy necessary for heating and cooling accounts for nearly 50% of the total energy cost for homes and other small structures. HVAC cooling options for such buildings has largely been limited to air source heat pumps and air source air conditioners for most consumers. However, the energy efficiency of air source heat pumps and air source air conditioners is dependent on the outdoor temperature and outdoor humidity. Water source heat pumps and water source air conditioners, available for large buildings, mid-rise and high-rise buildings, are designed to improve energy efficiency in high humidity and high temperature conditions. Unfortunately, the use of water source systems is limited for low-rise buildings and residences because of the large cooling towers and mist sprayers required on such systems.
Climate scientists split the Earth into approximately five main climate zones: tropical, dry, temperate, continental, and polar. The United States Department of Energy (“DOE”) divides these zones into eight climate regions: hot-humid, mixed-humid, hot-dry, mixed-dry, cold, very-cold, subarctic, and marine. Of these, the only DOE climate regions with efficient cooling by air source heat pumps and air conditioners are mixed-dry, cold, very-cold, and subarctic. This is because air source heat pump and air source air conditioner-based low-rise-building HVAC systems lose efficiency in high outdoor air humidity and/or high outdoor air temperature conditions.
For at least these reasons, a need exists for an improved misting system for condenser coils.

SUMMARY

A monitoring system is described for air conditioning and heat pump condensers (collectively, called outdoor condensing units). The monitoring system can include a controller that determines when to mist the condenser unit and at what intensity level. The decisions can be based on sensor information from compressor current sensors, compressor coil temperature sensors, refrigerant pressure sensors, and a fan motor current sensor, in an example.
The controller can be a microprocessor that monitors the control signals from the air handler and thermostat to determine if the condenser unit is on. When the condenser unit is on, the controller can determine a mist intensity based on environmental temperature, outdoor humidity, cooling loop liquid supply, and suction return line temperatures. These controller can use these factors to determine the optimal conditions to: a) open a solenoid valve simultaneously with compressor cooling operation, b) regulate water flow to provide the optimal volume of water mist onto the cooling fins through the system.
In one example, the system can include mist generators, such as nozzles, for attaching to an outside condenser unit of an air conditioning system. The nozzles can be attached to a pump that receives a control signal specified by the controller. The controller can detect an outdoor humidity level from one or more outdoor sensors. The controller can also detect that the condenser unit is on, such as by receiving heating and cooling calls from a thermostat.
In one example, the system can include ultrasonic mist generators with mist towers for attaching to an outside condenser unit of an air conditioning system. The mist generators can be attached to a flow regulator that receives water flow control signals specified by the controller. The controller can detect an outdoor humidity level from one or more outdoor sensors. The controller can also detect that the condenser unit is on, such as by receiving heating and cooling calls from a thermostat.
When the condenser unit is on and humidity and outdoor temperature levels meet thresholds, the controller can open a valve for supplying water to the pump. This can include opening a valve for a flow regulator that is part of the pump or attaches to the pump. The controller can adjust water flow rate based on the outdoor humidity level. This can cause the flow regulator or pump to move more or less water, depending on the environmental factors that influence the need for the misting. The pump supplies water to nozzles attached to the condenser unit according to the control signal while the flow regulator supplies water to the mist generators of the mist towers. In one example, the control signal is sent to the flow regulator, which is attached to the mist generators. In another example, the flow regulator is part of a pump and the control signal can be a power level that adjusts pump speed. Although the pump is referred to in examples below, it is understood that a pump can include flow regulation and that a separate flow regulator can be used in other examples.
The misting system for condenser coils can include an irrigation water filter, self-priming variable speed medium pressure fluid pump, flow regulator, low-voltage water-controlling irrigation, and solenoid valve. The pump, the controller, mist generators and spray-nozzles can, in one example: a) attach to an air conditioner; b) control and regulate specific quantity, angle and size of water particles (spray) to the cooling fins/coil; c) connect to a variety of water supplies. The controller can extend equipment longevity and saves electricity by causing a) decreasing air temperature near the condenser coil by mist cooling, b) increasing evaporative cooling of the condenser coil, c) facilitating rapid coolant conversion from gas to liquid in the condenser coil, and d) optimizing compressor head pressure to cool both faster and more efficiently. The self-priming pump can draw water from a pressurized or unpressurized supply-water and pump pressurized water through the water filter and solenoid valve under control of the microprocessor. The microprocessor can monitor the control signals from the air handler and thermostat along with environmental temperature and humidity and cooling loop liquid supply and suction return line temperatures to determine the optimal conditions to a) open the solenoid valve simultaneously with compressor cooling operation, and b) turn on the pump and regulate pump speed to provide the optimal volume of water mist onto the cooling fins through the system.
The system can deploy the right sized droplets at the right volume and speed. This can be based on current humidity levels, ensuring that the condenser is at the correct humidity. This can include dynamically varying the volume and particle size based on the compressor, in an example. The controller can ensure that the water is limited such that it insulates the coil and makes it less useful.
To do this, the system can utilize a variable speed pump to provide variable pressure for the mist particles. The pump can be hooked up to a hose, such as a conventional garden hose in an example. In another example, the water is filtered before entering the pump. In one example, an all-terrain vehicle (“ATV”) racing fuel pump can be repurposed for operation with water based on outputs from the controller.
The controller can be a microprocessor that monitors the control signals from the air handler and thermostat along with environmental temperature and humidity and cooling loop liquid supply and suction return line pressures, compressor coil temperature, compressor and fan motor current draw to determine the function of the monitored components, to identify malfunction of a monitored component, to monitor refrigerant pressure, and to identify refrigerant leaks. The system can report changes in component function and refrigerant pressure that require service via the wireless interface.
A monitoring system is described for air conditioning and heating air handler (collectively, called indoor air handler units). The monitoring system can include a controller that determines when to sanitize the evaporator coil, drip pan, air handler and air stream and at what intensity level. The decisions can be based on sensor information from air handler current sensors, evaporator coil temperature sensors, and a fan motor current sensor, in an example.
The controller can be a microprocessor that monitors the control signals from the air handler and thermostat to determine if the air handler fan unit is on. When the air handler fan unit is on, the controller can activate a UV sanitizer.
In one example, the system can include UV sanitizer panels for attaching to the inside of the air handler unit of an air conditioning system. The UV sanitizer panels can be attached above and below the condenser coil. The UV sanitizer panels receive a control signal specified by the controller.
When the air handler fan unit is on, the controller can activate the UV sanitizer. A safety switch can ensure that the UV sanitizer does not illuminate when the air handler casing is open. This feature protects people from exposure to UV radiation during servicing of the air handler.
The examples summarized above can each be incorporated into a non-transitory, computer-readable medium having instructions that, when executed by a processor associated with a computing device, cause the processor to perform the stages described.
Both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the examples, as claimed.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a flowchart of an example method for misting control for an outdoor condenser unit.

FIG. 2 is an example sequence diagram for misting control system at an outdoor condenser unit.

FIG. 3 is an example system diagram of components for controlled misting in an air conditioning system.

FIG. 4 is an example illustration of a condensing unit equipped with misting components.

DESCRIPTION OF THE EXAMPLES

Reference will now be made in detail to the present examples, including examples illustrated in the accompanying drawings. Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or like parts.
FIG. 1 is an example flowchart with stages performed by a controller for operating a misting system. The misting system can be attached to an outdoor condenser unit, which may be part of a heating, ventilation, and air conditioning (“HVAC”) system. The condenser unit can be part of any type of air conditioning system, such as a heat pump system. The controller can either be located indoors or mounted outdoors on the condenser unit, in various examples. A pump can be mounted to the condenser unit, along with a series of nozzles to mist the condenser coils. A water supply, such as a hose, can be attached to the pump.
At stage 110, the controller can detect an outdoor humidity level. This can be based on outdoor sensor information from one or more sensors. As will be described, the controller can control the pump based on current humidity and temperature information. The controller can continuously or periodically monitor humidity and temperature. In one example, the controller only monitors temperature and humidity when the condenser is on.
At stage 120, the controller can detect that the condenser unit is on. In one example, when there is a “cool on” signal from the thermostat, the controller can send requests for data to various sensors. The sensors can respond with the latest measurements captured. Simultaneously, when a “cool on” signal is received from the thermostat, the controller can determine if the temperature and humidity of outside air is appropriate for mist cooling of intake air and/or evaporative cooling of the condenser coil. To make this determination, the controller can compare condenser coil temperature to outdoor temperature and humidity, as shown in Equation 1, below.
Condenser Coil Temperature (° F.)>Outdoor Temperature (° F.)+((% humidity−0.6)*100)+10 Equation 1
In one example, the controller can open a water supply valve at stage 130 when the condenser unit is on and the outdoor sensor information dictates. For example, if there is a “cool on” signal from the thermostat and outside air temperature and humidity meets the requirements of Equation 1, the controller can command the irrigation valve solenoid to allow source water to flow to the fluid pump. The controller can also turn on power to the fluid pump motor.
At stage 140, the controller can control the volume of water provided for mist cooling of intake air and/or evaporative cooling of the condenser coil. To do this, the controller can vary the voltage supplied to the fluid pump motor, which change the speed at which the motor pumps water. The controller can vary the pump power voltage in response to coolant temperatures in the coolant evaporator suction return line and the coolant liquid supply line in relationship to the outdoor temperature and outdoor humidity. Sensors in or on the suction return line and coolant liquid supply line can supply sensor information used by the controller to calculate the voltage level. In one example, the controller can use Equation 2, below to determine the voltage (V).
V=[(8+(ET−37)*0.30556]+[(LT−OT)*0.28947]−[(H−90%)*289.47368] Equation 2
Where:

- V=Pump Motor Supply Voltage (DC)
- ET=Coolant Evaporator Line Temperature in ° F.
- LT=Coolant Liquid Line Temperature in ° F.
- OT=Outdoor Temperature in ° F.
- H=% Outdoor Humidity

In one example, the controller can continuously adjust pump voltage until an off condition exists. The off condition can occur when there is no longer a “cool on” signal from the thermostat. Alternatively, the off condition can occur when outside air temperature and humidity is no longer appropriate for mist cooling of intake air and/or evaporative cooling of the condenser coil—such through use of Equation 1. When an off condition exists, the controller can command the irrigation valve solenoid to stop source water flow to the fluid pump and turn off power to the fluid pump motor.
At stage 150, the pump supplies water to the nozzles according to the power level (i.e., voltage supplied from the controller). The nozzles can be part of a tubing loop or line that is attached to the condenser unit. The nozzles can spray the water such that a mist contacts the condenser lines. This can help with the heat transfer between the condenser lines and outdoor air.
The pump can variably operate between 50 to 160 psi operating pressure, depending on the voltage supplied from the controller. This can allow the pump to range between 5 to 20 gallon per hour output fluid pump.
FIG. 2 is an example sequence diagram for controlling misting for a condenser unit. At stage 205, the controller can detect that the HVAC system is on. This detection can be based on the controller monitoring control signals from the thermostat in the HVAC system. For example, the thermostat can send heating and cooling calls. In some HVAC systems, a cooling call causes condenser unit operation. In other HVAC systems, such as with a heat pump, the condenser can operate for heating and cooling calls. In another example, a sensor on a power line to the condenser unit can allow the controller to determine the outdoor condenser is on based on the voltage or current being supplied. For example, a current sensor can detect power flowing to the condenser blower.
In one example, if the condenser is on, the controller can begin determining whether to mist the condenser coils and the relative amount of water to apply. As part of this, at stage 210, sensors can provide humidity and temperature information to a controller. The sensors can provide both indoor and outdoor information, in an example. One or more of the sensors can be part of a sensor package, in an example. A sensor package can include a microprocessor board with memory and I/O connections, a temperature sensor, a humidity sensor, and various environmental sensors in an example. Alternatively, the system can use standalone sensors that produce sensor information interpreted by the controller.
In this example, at stage 210 an outdoor sensor can indicate a low humidity level, such below 55%. Sensor information can also indicate the outdoor air temperature, such as 85 degrees Fahrenheit.
At stage 215, the controller can send a signal to open the solenoid value and supply water to the pump. This signal can be based on the operational status detected at stage 205 and the outdoor sensor information of stage 210. For example, Equation 1 or a similar equation can be used to determine that outdoor air temperatures are high enough in combination with the humidity to warrant misting. This can allow the controller to ensure that water is not wasted and that the condenser coils are not excessively wet, in an example.
When the valve is open, the controller can also set the pump rate by supplying a voltage to the pump. In this example, at stage 220 the controller sends a voltage signal indicating a relatively high pump rate. This can be based, for example, on an outside temperature above 85 degrees Fahrenheit with a humidity below 60 percent.
The controller can continue to monitor condenser operation and sensor information and adjust the misting operation accordingly. For example, at stage 225 the controller can detect that humidity has increased. For example, the humidity may rise to 90%. As a result, less mist may be needed to keep the condenser coils sufficiently wet for increased heat transfer. This is because the evaporation of the mist can slow when the outside air is already very humid. As a result, at stage 240 a lower voltage can be sent to the pump, decreasing the water supply sent to the nozzles.
At stage 235, the controller can detect that the condenser is switched to off. This can occur when the desired indoor temperature is met, and the thermostat sends a signal to turn off air conditioning or end a cooling cycle. The controller can detect this operational change in the same manner as described for stage 205.
When the condenser is off, there is no need to continue misting the condenser. As a result, the controller can send a command to close the valve at stage 240. The controller can also send an “off” command to the pump, such as by ceasing to supply voltage, at stage 245. This can deactivate the pump and cause the nozzles to discontinue spraying mist on the condenser coils.
The controller can detect when the condenser operational state changes back to “on,” such as at stage 255. The controller can again retrieve the most recent temperature and humidity sensor information, such as at stage 250. In this example, a 100 percent humidity can indicate the presence of rain. Alternatively, temperatures approaching freezing can be detected by the controller. In either case, the controller can send a signal to close the valve at stage 260 and turn off the pump at stage 265. When rain exists, it can be wasteful to also mist the condenser coils and can also lead to excess moisture in the area of the condenser unit. Likewise, when cold temperatures exist, efficiency for heat transfer can fall to a level that nullifies practical advantages of the misting improvements. Preventing excess moisture in that scenario can become more important for purposes of preventing freezing of the condenser coils.
Later, at stage 270, the controller can detect reduced humidity and higher temperatures. In response, the controller can once again open the valve at stage 275 and supply a medium level voltage at stage 280.
This process can continue indefinitely, generating substantial operational cost savings for the HVAC system while avoiding issues related to excess moisture at the outdoor air condenser.
FIG. 3 is an example system diagram of components for controlled misting in an air conditioning system. In one example the control system can a controller 310. In one example, the controller 310 can include a microprocessor board with memory and input/output (“I/O”) connections (“COTS”). The controller can include custom hardware using COTS components, such as 24 volt AC to DC voltage converters, switches, relays, DC microprocessor controlled variable output DC converters, and a wireless communications interface. The controller 310 can read the various control lines of the HVAC system, read the data from sensors 312, 314, 316, 318 and control relays on a relay board, in an example.
To determine if the condenser unit 350 is on, the controller 310 can receive a signal from a thermostat 330 in an example. For example, the thermostat can send heating and cooling calls on various wires to the HVAC system. Those wires can be connected to the controller, in an example, or to a wireless module that communicates with the controller. The thermostat 310 can send signals to the air handler 340, which in turn can communicate with the condenser unit 350.
The controller 310 can alternatively determine operational state by monitoring signals for one or more of a mode control 342, blower control 344, and compressor mode 346. Since an HVAC system typically uses 24 volts AC and the controller can use DC voltage to operate, buffering between the two environments can be handled by a custom circuit—one circuit per HVAC line required to be monitored. In one example, the controller 310 only needs to detect the presence of 24 volts AC on a control line so an Optical Isolator (opto-isolator) is used to allow for this detection without imposing a burden onto the HVAC system. Resistors on the AC side can allow for the opto-isolator to interface with the HVAC system while resistors and capacitors on the DC voltage side allow for a steady output dependent on the state of the monitored HVAC line. The output on the DC voltage side is tied to an input on the processor board so the system can read the output state.
The controller can operate a valve 320 and pump motor 322. To turn the valve 320 on and off, the controller 310 can send a valve control signal to the valve 320. Likewise, the controller can vary the pump speed with a motor control voltage sent to the pump 322. The valve 320 can be a 24-volt AC solenoid irrigation water valve with three-quarter-inch pipe size, in an example. The valve 320 can be attached to or integrated with pump 322. The assembly can include a three-quarter-inch water filter and a garden hose fitting, in an example. The pump 322 can include a self-priming variable speed DC voltage, high pressure, high gallon per hour (“GPH”), fluid pump, in an example. The pump assembly can include both the valve 320 and pump 322 and can be weatherproof in an example. The pump assembly can attach to a nozzle assembly or mist generator in an example.
The control system can control the irrigation valve 320 by applying or removing 24 volts AC to the solenoid control lines. Similarly, the system controls power to the fluid pump 322 by applying or removing varying DC power to the power lines of the fluid pump motor. These voltages can be interrupted with a relay board, in an example.
To determine when and how to operate the valve 320 and pump 322, the controller 310 can receive sensor information from various sensors. In one example, an Outdoor Air Quality (“OAQ”) sensor package 312 can include COTS components. The controller 310 can request data from the OAQ sensor package 312, and the OAQ sensor package can send sensor information related to temperature and humidity. The OAQ sensor package can include an array of sensors for detecting temperature and humidity.
In one example, a condenser coil temperature sensor 314 can provide the temperature of the condenser coil. This sensor 314 can clamp onto the condenser coil, in an example. To determine whether open the valve 320 or in adjusting the pump 322 level, the controller can compare condenser coil temperature to a function output of the outdoor temperature and outdoor humidity.
An evaporator line sensor 316 or coolant liquid supply line sensor 318 likewise can allow the controller to adjust misting downward when the evaporator line is already beneath a coldness threshold. The control system can use data from a combination of sensor arrays to determine if, when, and what volume of filtered water mist is appropriate to optimize operating efficiency for each HVAC operational cycle.
In one example, the controller 310 can connect to the internet and local internet protocol (“IP”) network via a wireless communications interface module installed in the Main Controller case. Internet connectivity can be used for user interactions and system functions including but not limited to the items in Table 1, below.

	TABLE 1

	Display Outdoor Air Temp and Humidity
	Display Refrigerant Evaporator Line Pressure
	Display Refrigerant Condenser Coil Temp
	Display Refrigerant Liquid Supply Line Pressure
	Display Compressor Current Draw
	Display Fan Current Draw
	Display Water Valve On/Off State
	Display Fluid Pump Speed/Voltage
	User Notifications
	Store, Display and Export Outdoor Temp and
	Humidity, Refrigerant Line Temps, Condenser Temp,
	Valve State and Fluid Pump Parameters over time
	Graph Outdoor Temp and Humidity, Refrigerant Line
	Temps, Condenser Temp, Valve State and
	Fluid Pump Parameters over time
	Pause/Deactivate Automated Mist Functions
	Communicate with other Natural Air E-Controls
	Products and Services
	Software Updates

In one example, the control system is designed to use water from both pressurized and unpressurized filterable water sources common to low-rise building and residential communities. The COTS three-quarter-inch hose fitting of the COTS inline water filter provides connection for supply water. The water filter screws into the three-quarter-inch fitting of the COTS irrigation valve which controls water flow to the connected self-priming variable speed fluid pump. Water leaves the pump through a COTS three-sixteenth-inch fluid line that forms a loop terminating in a COTS auto drain valve. The COTS Tee fittings and COTS mist nozzles/mist generators along the COTS fluid line produce the mist for mist cooling of intake air and evaporative cooling of the condenser coil.
The controller 310 can operate with an outdoor air quality (“OAQ”) sensor package. The Outdoor Sensor Package can include a processor board, a temperature sensor and a humidity sensor. The data from the sensor array is combined by the on-board processor in the Air Quality Sensor Package, evaluated for their validity then packaged into data-packets and made available to the Main Controller via a four-wire cable using a common data protocol. Pull-up resistors on the data-lines allow for transmission over the wires at distances greater than 100 feet. Sensor packages are powered by a common DC voltage regulated power-supply. Since the temperature and humidity sensors operates at a lower voltage, a COTS DC voltage level shifter is utilized to regulate the DC voltage supply to the voltage required by the gas sensor. Data to and from the gas sensor is buffered by the DC voltage level shifter. An example sensor array is shown in FIG. 8.
The controller 310 can operate according to settings on a mobile application or web interface in one example. For simplicity, the mobile application is discussed but the same concepts are possible for the web interface. The mobile application can allow a user to set temperature and humidity thresholds for powering on the misting, in an example. The mobile application can allow the user to also set misting intensity so that the controller ramps up pump 322 speed according to a user-defined set of temperature and humidity thresholds.
The mobile application can also allow the user to view various statistics about the control system. For example, the mobile application can have user-selectable options, including:

- Display Outdoor Air Temp and Humidity;
- Display Refrigerant Evaporator Line Pressure;
- Display Refrigerant Condenser Coil Temp;
- Display Refrigerant Liquid Supply Line Pressure;
- Display Compressor Current Draw;
- Display Fan Current Draw;
- Display Water Valve On/Off State;
- Display Fluid Pump Speed/Voltage;
- User Notifications;
- Store, Display and Export Outdoor Temp and Humidity, Refrigerant Line Temps, Condenser Temp, Valve State and Fluid Pump Parameters over time;
- Graph Outdoor Temp and Humidity, Refrigerant Line Pressure, Condenser Temp, Current Draws, Valve State and Fluid Pump Parameters over time; and
- Pause /Deactivate Automated Mist Functions.

The mobile application can also be set to control the misting system according to US DOE climate regions, which can have different default thresholds for adjusting pump power.
In one example, the controller 310 can also activate an ultraviolet sanitizer module 341 that sanitizes the evaporator coils of the air handler. The UV sanitizer module 341 can be powered by a 240V A/C source in one example. The UV sanitizer module 341 can include two or three UV sanitizer illumination panels positioned inside the air handler to sanitize the surfaces of the evaporator coil, drip pan and air handler walls.
FIG. 4 is an example illustration of a condensing unit 400 equipped with misting components. In one example, a pump housing 420 is mounted to the condensing unit 400. The pump housing 420 can weatherproof the pump 322 and valve 320, in an example. A water supply inlet 422 can be attached to a hose or other water source.
A nozzle tube 430 can be attached to the pump 322 and the condenser unit 400. The nozzle tube 430 can include multiple nozzles 432 for misting purposes. In this example, four nozzles 432 are provided, but other configurations are possible. The nozzles 432 can be oriented to spray mist on condenser coils within the condenser unit 400. When the fan 440 is on, the mist can be drawn in through vents 450 in the sides of the condenser unit 400, in an example.
Additionally, controller housing 410 can house the controller 310. The controller housing 410 can be installed on the condenser unit 400 or elsewhere, depending on the example. The controller can monitor function of the outside compressor unit (e.g., AC or Heat Pump) in both cooling and heating cycles, in an example. As described above, the monitoring can be based on an outdoor air temperature sensor and outdoor air humidity sensor. In addition, the controller can utilize a current sensor circuit to monitor fan and compressor motor operation and energy use and determine that the operational state is on. The controller can also use a pressure sensor to monitor refrigerant pressure and compressor output. Further, the controller can utilize refrigerant temperature sensors to monitor compressor output and coil efficiency.
The UV sanitizer system can be attached to an air handler unit, which may be part of the HVAC system. The air handler unit can be part of any type of air conditioning system, such as a heat pump system. The controller can be located indoors on or inside the air handler unit, in various examples. UV sanitizer illumination panels can be mounted inside the air handler unit above and below the evaporator coil(s). A safety switch is located at the access panel to deenergize the UV sanitizer illumination panel when the air handler access panel is open. The controller can detect that the air handler fan is on. This can be based on current sensor information from one or more sensors or on the detection of a “fan on” signal from the thermostat. As will be described, the controller can control the UV sanitizer. The controller can detect that the air handler unit access panel is closed. In one example, there can be a safety switch that signals the controller that the access panel is closed. The controller can energize the UV sanitizer illumination panels.
This process can continue indefinitely, generating substantial operational safety for the building occupants served by the HVAC system while avoiding issues related to excess moisture at the air handler and ducts.
Other examples of the disclosure will be apparent to those skilled in the art from consideration of the specification and practice of the examples disclosed herein. Though some of the described methods have been presented as a series of steps, it should be appreciated that one or more steps can occur simultaneously, in an overlapping fashion, or in a different order. The orders of steps presented are only illustrative of the possibilities and those steps can be executed or performed in any suitable fashion. Moreover, the various features of the examples described here are not mutually exclusive. Rather any feature of any example described here can be incorporated into any other suitable example. It is intended that the specification and examples be considered as exemplary only, with a true scope and spirit of the disclosure being indicated by the following claims.

Claims

What is claimed is:

1. A misting system co control signal mprising:

mist generators for attaching to an outside condenser unit of an air conditioning system;

a flow regulator coupled to the mist generators; and

a controller that communicates with the flow regulator, wherein the controller performs stages comprising:

detecting an outdoor humidity level;

detecting that the condenser unit is on;

opening a valve for supplying water to the flow regulator when the condenser is on; and

adjusting a control signal to the flow regulator based on the outdoor humidity level,

wherein the flow regulator supplies water to mist generators attached to the condenser unit according to the control signal.

2. The system of claim 1, wherein detecting that the condenser is on includes receiving a signal from a thermostat.

3. The system of claim 1, the stages further comprising:

detecting an outside air temperature by receiving information from a sensor; and

wherein adjusting the control signal to the flow regulator is further based on the outside air temperature.

4. The system of claim 3, wherein the controller opens the valve based on calculating that a condenser coil temperature is greater than a function of the outdoor temperature and outdoor humidity.

5. The system of claim 3, wherein the control signal to the flow regulator varies a water flow rate.

6. The system of claim 1, wherein the control signal is adjusted based on a first temperature of coolant in a suction return line and a second temperature in a liquid supply line, the first and second temperatures being weighted relative to an outdoor temperature and the outdoor humidity.

7. The system of claim 1, the stages further comprising sending a sanitation signal that causes an ultraviolet light panel in an indoor unit to sanitize an evaporator coil.

8. A method for providing mist control for an outside condenser unit of an air conditioning system, comprising:

detecting, at a controller, an outdoor humidity level based on outdoor sensor information;

detecting, at the controller, that the condenser unit is on;

opening a valve for supplying water to a flow regulator when the condenser unit is on; and

9. The method of claim 8, wherein detecting that the condenser unit is on includes receiving a signal from a thermostat.

10. The method of claim 8, further comprising:

11. The method of claim 10, wherein the controller opens the valve based on calculating that a condenser coil temperature is greater than a function of the outdoor temperature and outdoor humidity.

12. The method of claim 10, wherein the control signal causes a pump to vary a pump motor speed.

13. The method of claim 8, wherein the control signal is adjusted based on a first temperature of coolant in a suction return line and a second temperature in a liquid supply line, the first and second temperatures being weighted relative to an outdoor temperature and the outdoor humidity.

14. The method of claim 8, further comprising sending a sanitation signal that causes an ultraviolet light panel in an indoor unit to sanitize an evaporator coil.

15. A non-transitory, computer-readable medium containing instructions for providing mist control for an outdoor condenser unit, the instructions executed by a controller to perform stages comprising:

detecting, at the controller, that the condenser unit is on;

opening a valve for supplying water to a pump when the condenser unit is on; and

adjusting a control signal to the pump based on the outdoor humidity level,

wherein the pump supplies water to mist generators attached to the condenser unit according to the control signal.

16. The non-transitory, computer-readable medium of claim 15, wherein detecting that the condenser unit is on includes receiving a signal from a thermostat.

17. The non-transitory, computer-readable medium of claim 15, the stages further comprising:

wherein adjusting the control signal to the pump is further based on the outside air temperature, and wherein the control signal is sent to a flow regulator that is attached to the mist generators.

18. The non-transitory, computer-readable medium of claim 17, wherein the controller opens the valve based on calculating that a condenser coil temperature is greater than a function of the outdoor temperature and outdoor humidity.

19. The non-transitory, computer-readable medium of claim 17, wherein the control signal to the pump varies a pump motor speed.

20. The non-transitory, computer-readable medium of claim 15, wherein the control signal is adjusted based on a first temperature of coolant in a suction return line and a second temperature in a liquid supply line, the first and second temperatures being weighted relative to an outdoor temperature and the outdoor humidity.