US1984866A - Air humidification apparatus - Google Patents

Air humidification apparatus Download PDF

Info

Publication number
US1984866A
US1984866A US541242A US54124231A US1984866A US 1984866 A US1984866 A US 1984866A US 541242 A US541242 A US 541242A US 54124231 A US54124231 A US 54124231A US 1984866 A US1984866 A US 1984866A
Authority
US
United States
Prior art keywords
air
drum
water
heating
casing
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US541242A
Inventor
Vincent S Day
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Carrier Engineering Corp
Original Assignee
Carrier Engineering Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Carrier Engineering Corp filed Critical Carrier Engineering Corp
Priority to US541242A priority Critical patent/US1984866A/en
Application granted granted Critical
Publication of US1984866A publication Critical patent/US1984866A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24HEATING; RANGES; VENTILATING
    • F24DDOMESTIC- OR SPACE-HEATING SYSTEMS, e.g. CENTRAL HEATING SYSTEMS; DOMESTIC HOT-WATER SUPPLY SYSTEMS; ELEMENTS OR COMPONENTS THEREFOR
    • F24D5/00Hot-air central heating systems; Exhaust gas central heating systems

Definitions

  • This invention relatesto a unit apparatus for conditioning an atmosphere, and more'particularly to an arrangement for humidifying a volume of air treated by the unit.
  • a featurepof the invention resides inthe arrangement'of an evaporator in combination with a circulating; system served by a source of heat independent lof an associated heating apparatus forming'prt of a unified system.
  • the positioning of th'e evaporator in a location substantially removed from the influence of heating apparatus belonging to the same air conditioning unit allows the rate of evaporation to be controlled independently of the heating process carried on fontemperature control.
  • Another' feature resides in the positioning of the evaporator at the point of discharge of the airserved by theunit, so' that effective humidication may take place and the evaporation process aided.
  • Fig. 1 is a diagrammatic representation of an air conditioning apparatus incorporating a hu- 15 midification system in accordance with'the invention.
  • Fig. 2 is a detail showing an arrangement for feeding water to the humidification system
  • Figs. 3 and 4 illustrate the accessibility of the 20 heating drum and the method of applyingheat to the water circulation system
  • Fig. 5 is a plan view of the piping and circulation arrangement
  • Fig. 6 is a detail showing the method of seg- 25 regating the water drum of the circulationsystem from th-e rest of the unit.
  • numeral 7 designates, generally, an air conditioning unit suitable for controlling the temperature and relative humidity of an enclosure connected by ducts to outlet A8.
  • the apparatus includes inlet 9 for air from any desired source, filters 10, fan 11, fire' box 12, burners 13 .Within the fire box for heating 35 air, burners 14 for heating water drum 16, shield 15 segregating water drum 16 from the rest of the fire box, interchangers 17 and 18, header 19, cooling chamber 20 for products of combustion, diverter 21 for mixing products of combustion with air drawn in from surroundingatmosphere and iiue 22. As indicated by the arrows ⁇ ,'the air indrawn through inlet 9 is first filtered and then sent to the conditioning portion ⁇ of the unit by the fan.
  • 'Ihe humidication apparatus comprises a water circulating system, including open water trough 23, water channels or pipes 24 and 25 55 (hereinafter described in detail) adapted to maintain a predetermined level of water within the trough 23.
  • the iioat arrangement 30 (Fig. 2) is mounted near the trough 23 and a pipe connecting the two has its discharge adjacent the entrance of pipe 25. Cool Waterfrom 30 enters the trough and establishes a temperature differential between the water at one end of the trough and at the other. Hence, a circulation of water between the drum 16 and the trough 23 will be established by thermosyphon action.
  • the drum is located within the fire box, but is effectively segregated from the effect of the burners 13 by the confining shield 15.
  • the drum is therefore subject only to the inuence of its related set of burners 14 which serve the humidication system and remains uninfluenced by the burning equipment used for temperature control of the air served by the unit.
  • elements 26 provide sealing joints at the points where pipes 24 and 25 enter the i'lre box. These pipes are connected to the drum in any suitable manner. and 6, elements 26 are mounted in contact with wall 27 of the re box and are retained in sealing position by spring 28 arranged between the element and fitting 29.
  • the water in the humidification apparatus is retained at a desired level by means of float apparatus 30, of any usual type, connected to a source of supply.
  • the float arrangement 30 comprises a tank in communication with trough 23.
  • a float adapted to operate a valve, thereby controlling the admission of water to the tank from any suitable source, in response to changes linthe level of water therein. Since the tank and trough 23 are in communication, it is obvious that the float, in responding to changes in level in the tank, simultaneously responds to changes in the level of water in the trough.
  • Figs. 3 and 4 show the assembly of the drum in the unit, with its independent burners 14, served by gas supply from any desired source through pipe 31, and more particularly denote the ease with which the interior of drum 16 may be made accessible. As illustrated, drum 16 terminates in a flange 32 suitably mounted in the outer wall 33 of Vthe unit.
  • burning equipment for humidication and heating is thu's concentrated at one point of the apparatus, and yet independent heating is provided for the humidier, separate and unrelated to the air heater.
  • the provision of burner equipment at the bottom of the unit, where it most logically belongs enables maximum circulation between the drum and the evaporator comprising through 23 which is best adapted to function at the top of the unit, apart from and uninfluenced by the heating equipment, and in position where maximum contact with the all' will take place prior to direct discharge from the unit.
  • the provision of the trough near outlet 8 assures issuing the humidied air at the temperature it leaves the unit, since it then has no opportunity to be affected by any of the heating apparatus in the unit. Humidication, therefore, remains independent at all points in the unit, without relation 'to the apparatus for heating the air.
  • a casing for the main portion of air supplied by said fan, air humidifying means, and a partition between said rebox and said casing, said partition forming a passageway with said casing for diverting a portion of the air supplied by said fan to said humidifying means, said partition forming a passageway with said flrebox for diverting another portion of the air supplied by said fan over the surfaces of said frebox to cool it.
  • a combination of apparatus for heating and humidifying air a casing, a rebox in said casing, a heat interchanger in communication with said flrebox, an evaporator comprising an open water trough, a fan for supplying air to said casing and over the outer surfaces of said interchanger, a conduit for supplying av portion of air from said fan over said evapcrator without Icontacting said 1,os4,ssa
  • a combination of apparatus for heating and humidifying air a casing, a tan tor supplying air to said casing, a rebox in said casing, a heat interchanger in communication with said iirebox, a passageway formed by the outer surfaces of said interchanger and a portion of said ilreboxv for the main portion of air supplied by said fan, an evaporator comprising an open water trough, a partition between said casing and a portion of said rebox, a first passageway formed between 'said casing and said partition for conveying a small portion of the 'air supplied by said Ian over said evaporator without contacting said interchanger, a second passageway formed between said partition and said rebox for conveying another small.
  • a combination of apparatus for heating and humidifying air a casing, a fan for supplying air to said casing, a rebox in said casing, a heat interchanger in communication with said rebox,
  • a ilrst set of burners for heating said interchanger, an enclosed water drum, ⁇ a pair of pipes for connecting said drum to said evaporator, a second set of burnersfor heating said drum to cause a circulation of water through said pipes and said evaporator, and a ilrebox for containing said water drum and both of said sets of burners.
  • a combination ot -apparatus for heating and humidifying air a casing, a fan for supplying air to said casing, a iirebox in said casing, a heat vinterchanger in communication with said nrebox, means in said rebox for heating said interchanger, a passageway formed by the outer surfaces ofV said interchanger and a portionI of the outer surfaces of said irebox ⁇ for the main por- .tion of air supplied by said fan, a partition between said casing and a.
  • an open water trough mounted between said casing and said partition, an enclosed water drum in said rebox, a plurality of pipes between said drum and said water trough, means in said firebox for heating said drum to cause a circulation of water through said pipes and said water trough, a iirst passageway between said partition and said casing for conveying a portion of the air supplied by said fan over said water trough without contacting said interchanger, a second passageway between said partition and said rebox for conveying another small portion of air over said rebox without contacting said water trough or said interchanger, vand a 'duct for collecting air from all of said passageways.
  • a combination of apparatus for heating and humidifying air a casing, a fan 'for supplying air to said casing, a rebox in said casing, a heat interchanger in communication with said rebox, a passageway formed by the outer surfaces of said interchanger anda portion of the outer surfaces of said rebox through which the main portion of air supplied bysaid fan is passed, an open water trough, a passageway for conveying a small portion of the air supplied by the fan 'over said water trough without contacting saidy interchanger, a conduit for collecting air from vboth of said passageways, a ilrst -set of burners 'in said ilrebox for heating said interchanger, an enclosed water drum in said rebox, a plurality oi? pipes connecting said drum to said water trough.

Landscapes

  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Air Humidification (AREA)

Description

Dec. 18, 1934. y, s, DAY I 1,984,866
AIR HUMIDIFICATION APPRATUS INVENTOR ATTORNEY Dec. 18, 1934. v. s. DAY 1,984,866
AIR HUMIDIFICAT ION APPARATUS Filed June l, 1951 2 Sheets-Sheet 2 so iis; 5 LiL E'- 25 H-I l 2g l ,l h i 16/ i l l m 32 INVENToR 34 V//V'f/Vf /VY ATTORN EY Patented Dec. 18, 1934 'UNITED STATES l AIR HUMIDIFICATION APPARATUS Vincent S. Day, Summit; N. J., assignor, by mesne assignments, to Carrier Engineering Corporation, Newark, N. J., a corporation of New York Application June 1, 1931, serial No. 541,242
7 claims. (c1. 12s-11s) This invention relatesto a unit apparatus for conditioning an atmosphere, and more'particularly to an arrangement for humidifying a volume of air treated by the unit.
The general object of the invention is to provide a water circulating system, including an evaporator and affording means for controlling the temperature of the water, and hence the rate of evaporation in conditioning systems, where desired volumes of air are treated at one point and then distributed by means of a fan or otherwise to the conditioned area, and wherev it is desirable to control both the temperature and relative humidity of the air at the point of conditioning.
The requirements of temperature and humidity, however, may vary or may change, and not at the same rate. Thus, a high or low temperature may be desired for different purposes with dif-y fecting the one condition must be kept independent of those relating to the other.
A featurepof the invention resides inthe arrangement'of an evaporator in combination with a circulating; system served by a source of heat independent lof an associated heating apparatus forming'prt of a unified system. The positioning of th'e evaporator in a location substantially removed from the influence of heating apparatus belonging to the same air conditioning unit allows the rate of evaporation to be controlled independently of the heating process carried on fontemperature control.
Another' feature resides in the positioning of the evaporator at the point of discharge of the airserved by theunit, so' that effective humidication may take place and the evaporation process aided.
Another feature covers the employment of a heating drum as part of the circulation system having an outlet readily accessible from without the unit. 'I'his enables the circulation system to be speedily drained and the drum easily cleaned and scaled. Since the drum is subjected to relatively high temperatures, its interior should he periodically cleaned in order that circulation may not be impeded. The feature providing for easy access is not merely for convenience alone, but
insures maintaining the evaporation process at maximum elciency.
A further feature provides for a'water circulation system used for humidicatlon purposes in an air conditioning unit wherein one part is located within a fire box of the unit and the rest of the system is located outside. Meansare provided for effectively separating the fire box area from the rest of the unit at the points of con- 5 nection of the portions of the circulating system within and without the fire box.
Other objects and features, covering advantagesof design and construction. and making for economy in operation, will be moreapparent from 10 the following detailed description of one form of the invention, to be read in connection with the accompanying drawings, in which:
Fig. 1 is a diagrammatic representation of an air conditioning apparatus incorporating a hu- 15 midification system in accordance with'the invention.
Fig. 2 is a detail showing an arrangement for feeding water to the humidification system,
Figs. 3 and 4 illustrate the accessibility of the 20 heating drum and the method of applyingheat to the water circulation system,
Fig. 5 is a plan view of the piping and circulation arrangement, and
Fig. 6 is a detail showing the method of seg- 25 regating the water drum of the circulationsystem from th-e rest of the unit.
Considering the drawings, similar' designations referring to similar parts, numeral 7 designates, generally, an air conditioning unit suitable for controlling the temperature and relative humidity of an enclosure connected by ducts to outlet A8. The apparatus includes inlet 9 for air from any desired source, filters 10, fan 11, fire' box 12, burners 13 .Within the fire box for heating 35 air, burners 14 for heating water drum 16, shield 15 segregating water drum 16 from the rest of the fire box, interchangers 17 and 18, header 19, cooling chamber 20 for products of combustion, diverter 21 for mixing products of combustion with air drawn in from surroundingatmosphere and iiue 22. As indicated by the arrows`,'the air indrawn through inlet 9 is first filtered and then sent to the conditioning portion `of the unit by the fan. Part of the air proceeds above. the fire 45l box and through the first interchanger, whereas anothe'r portion goes directly to the second interchanger. Still another part ofthe air is routed around the fire box and bypasses the in- I terchangers. 'I'his bypassed. air, however, is 50 forced i'nclose proximity `to `trough 23 of the humidication arrangement.
'Ihe humidication apparatus comprises a water circulating system, including open water trough 23, water channels or pipes 24 and 25 55 (hereinafter described in detail) adapted to maintain a predetermined level of water within the trough 23. The iioat arrangement 30 (Fig. 2) is mounted near the trough 23 and a pipe connecting the two has its discharge adjacent the entrance of pipe 25. Cool Waterfrom 30 enters the trough and establishes a temperature differential between the water at one end of the trough and at the other. Hence, a circulation of water between the drum 16 and the trough 23 will be established by thermosyphon action. The drum is located within the lire box, but is effectively segregated from the effect of the burners 13 by the confining shield 15. The drum is therefore subject only to the inuence of its related set of burners 14 which serve the humidication system and remains uninfluenced by the burning equipment used for temperature control of the air served by the unit. In order to confine the products of combustion within the lire box, elements 26 provide sealing joints at the points where pipes 24 and 25 enter the i'lre box. These pipes are connected to the drum in any suitable manner. and 6, elements 26 are mounted in contact with wall 27 of the re box and are retained in sealing position by spring 28 arranged between the element and fitting 29. The water in the humidification apparatus is retained at a desired level by means of float apparatus 30, of any usual type, connected to a source of supply. For example, the float arrangement 30 comprises a tank in communication with trough 23. Within the tank is a float adapted to operate a valve, thereby controlling the admission of water to the tank from any suitable source, in response to changes linthe level of water therein. Since the tank and trough 23 are in communication, it is obvious that the float, in responding to changes in level in the tank, simultaneously responds to changes in the level of water in the trough. Figs. 3 and 4 show the assembly of the drum in the unit, with its independent burners 14, served by gas supply from any desired source through pipe 31, and more particularly denote the ease with which the interior of drum 16 may be made accessible. As illustrated, drum 16 terminates in a flange 32 suitably mounted in the outer wall 33 of Vthe unit. Any methodof fixing the drum in position may be utilized, the important feature being to have the ange or extremity of the drum atv the outer wall of the unit apparatus. In the particular arrangement illustrated, ange 32 receives cover 34 which is securely bolted to the flange, suitable packing or gasket being employed in the usualmanner. The cover may, therefore, be quickly removed from outside the unit, making the interior of the'drum available for cleaning of scaling. If desired, a spigot or drain v35 may be fitted within the cover so that the humidiflcation system may be drained before the cover is removed. Sinceit may often be inconvenient to remove the cover on one side of the unit, similar assembly is provided on opposite sides, so that the drum is accessible from either side and easily cleaned.
In practice, some of the air enteringv the unit will be sent around partitions or shielding 36 which effectively separates the heating apparatus This air will, therefore, remain substantially unaffected by the heating apparatus and will be subject only to the influence of evaporation taking place from the open faced trough. The rate vof evaporation will depend In the arrangement shown in Figs. 5-
y 1,984,866 heating drum 16, and a float arrangement 30- upon the operation 'of burners 14 serving the drum, and these burners may be controlled in any suitable manner to provide desired humidiflcation. It may be noted that the air passing between partition 36 and the outer extremities of the unit will pass in close proximity to the trough and be deflected by baflie 37 downwardly toward the trough. The resultant intimacy of contact between the moving air and water, which, in practice, is at times so great as to agtate the water, aords great efficiency in securing maximum humidiflcation. After leaving the trough, the humidied air enters outlet 8 and thence to the area served by the unit. It may be noted that air collecting tube 38 which is used for removing heated air for raising the temperature Within ue 22 is` sopositioned that 4it will not remove any humidied air, all of which is free to proceed sembly and marked economy in operation. The
burning equipment for humidication and heating is thu's concentrated at one point of the apparatus, and yet independent heating is provided for the humidier, separate and unrelated to the air heater. Also, the provision of burner equipment at the bottom of the unit, where it most logically belongs, enables maximum circulation between the drum and the evaporator comprising through 23 which is best adapted to function at the top of the unit, apart from and uninfluenced by the heating equipment, and in position where maximum contact with the all' will take place prior to direct discharge from the unit. lThe provision of the trough near outlet 8 assures issuing the humidied air at the temperature it leaves the unit, since it then has no opportunity to be affected by any of the heating apparatus in the unit. Humidication, therefore, remains independent at all points in the unit, without relation 'to the apparatus for heating the air.
invention could be made without departing from the scope thereof, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.
Having described my invention, what I claim as new and desire to secure by Letters Patents,
1. In an air conditioning unit, a casing, a rebox in said casing, a heat interchanger in communication with said frebox, a fan for supplying air to said casing, the surfaces of said rebox and said interchanger forming a passageway. for the main portion of air supplied by said fan, air humidifying means, and a partition between said rebox and said casing, said partition forming a passageway with said casing for diverting a portion of the air supplied by said fan to said humidifying means, said partition forming a passageway with said flrebox for diverting another portion of the air supplied by said fan over the surfaces of said frebox to cool it.
2. A combination of apparatus for heating and humidifying air, a casing, a rebox in said casing, a heat interchanger in communication with said flrebox, an evaporator comprising an open water trough, a fan for supplying air to said casing and over the outer surfaces of said interchanger, a conduit for supplying av portion of air from said fan over said evapcrator without Icontacting said 1,os4,ssa
interchanger, a first set of barriers in said rebox, an enclosed water drum' in said tlrebox, a shield between said flrst set of burners and s aid water drum, a plurality of pipes connecting Athe drum and the evaporator, and a second set of burners for heating said'water drum to cause a circulation of water through'said drum, said pipes and said evaporator. V
3. A combination of apparatus for heating and humidifying air, a casing, a tan tor supplying air to said casing, a rebox in said casing, a heat interchanger in communication with said iirebox, a passageway formed by the outer surfaces of said interchanger and a portion of said ilreboxv for the main portion of air supplied by said fan, an evaporator comprising an open water trough, a partition between said casing and a portion of said rebox, a first passageway formed between 'said casing and said partition for conveying a small portion of the 'air supplied by said Ian over said evaporator without contacting said interchanger, a second passageway formed between said partition and said rebox for conveying another small.
v portion of the air supplied by said fan over the surfaces of said rebox to cool said rebox and substantially to prevent the heating of air in said rst passageway, a iirst set of burners in saidrebox for heating said interchanger, a water drum in said iirebox, a plurality of pipes between said water drum and said evaporator, and a second set of burners in said iirebox for heating said water drum to` causea circulation of water through said drum and said evaporator.
'4. A combination of apparatus for heating and humidifying air, a casing, a fan for supplying air to said casing, a rebox in said casing, a heat interchanger in communication with said rebox,
. aV passageway formed by the outer surfaces of said interchanger and a portion of said iirebox .10 forvthe main portion of aix' supplied" by said ian,
an open water trough, a conduit for ,conveying a small portion of the air supplied by said fan over said water trough without contacting said' humidifying air, a heat interchanger inv said 'cas-1 ing, a fan for supplying air to said casing and for discharging the main portion thereof over said 55 interchanger, an evaporator comprising an open,
3 portion of the air supplied by said fan over said evaporator without contacting said interchanger,
a ilrst set of burners for heating said interchanger, an enclosed water drum, `a pair of pipes for connecting said drum to said evaporator, a second set of burnersfor heating said drum to cause a circulation of water through said pipes and said evaporator, and a ilrebox for containing said water drum and both of said sets of burners.
6. A combination ot -apparatus for heating and humidifying air, a casing, a fan for supplying air to said casing, a iirebox in said casing, a heat vinterchanger in communication with said nrebox, means in said rebox for heating said interchanger, a passageway formed by the outer surfaces ofV said interchanger and a portionI of the outer surfaces of said irebox` for the main por- .tion of air supplied by said fan, a partition between said casing and a. portion of said rebox, an open water trough mounted between said casing and said partition, an enclosed water drum in said rebox, a plurality of pipes between said drum and said water trough, means in said firebox for heating said drum to cause a circulation of water through said pipes and said water trough, a iirst passageway between said partition and said casing for conveying a portion of the air supplied by said fan over said water trough without contacting said interchanger, a second passageway between said partition and said rebox for conveying another small portion of air over said rebox without contacting said water trough or said interchanger, vand a 'duct for collecting air from all of said passageways.
7. A combination of apparatus for heating and humidifying air, a casing, a fan 'for supplying air to said casing, a rebox in said casing, a heat interchanger in communication with said rebox, a passageway formed by the outer surfaces of said interchanger anda portion of the outer surfaces of said rebox through which the main portion of air supplied bysaid fan is passed, an open water trough, a passageway for conveying a small portion of the air supplied by the fan 'over said water trough without contacting saidy interchanger, a conduit for collecting air from vboth of said passageways, a ilrst -set of burners 'in said ilrebox for heating said interchanger, an enclosed water drum in said rebox, a plurality oi? pipes connecting said drum to said water trough.
' VINCENT S. DAY.
water trough, a conduit for conveying a small
US541242A 1931-06-01 1931-06-01 Air humidification apparatus Expired - Lifetime US1984866A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
US541242A US1984866A (en) 1931-06-01 1931-06-01 Air humidification apparatus

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US541242A US1984866A (en) 1931-06-01 1931-06-01 Air humidification apparatus

Publications (1)

Publication Number Publication Date
US1984866A true US1984866A (en) 1934-12-18

Family

ID=24158765

Family Applications (1)

Application Number Title Priority Date Filing Date
US541242A Expired - Lifetime US1984866A (en) 1931-06-01 1931-06-01 Air humidification apparatus

Country Status (1)

Country Link
US (1) US1984866A (en)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2740396A (en) * 1953-02-02 1956-04-03 Skuttle Mfg Company Humidifier apparatus
US3016892A (en) * 1958-06-04 1962-01-16 Ervin J Sperath Humidifier
US3302630A (en) * 1965-10-18 1967-02-07 Home Furnace Company Hot air furnace
US3841301A (en) * 1973-02-27 1974-10-15 Atlanta Stove Works Inc Heat exchanger for wall furnace

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2740396A (en) * 1953-02-02 1956-04-03 Skuttle Mfg Company Humidifier apparatus
US3016892A (en) * 1958-06-04 1962-01-16 Ervin J Sperath Humidifier
US3302630A (en) * 1965-10-18 1967-02-07 Home Furnace Company Hot air furnace
US3841301A (en) * 1973-02-27 1974-10-15 Atlanta Stove Works Inc Heat exchanger for wall furnace

Similar Documents

Publication Publication Date Title
US4401261A (en) Flue gas heat recovery apparatus
US2827893A (en) Furnace system for heating air and water
US2160269A (en) Air heating and conditioning unit
US1984866A (en) Air humidification apparatus
US2089407A (en) Air conditioning furnace
US2023622A (en) Air conditioning apparatus
US2150514A (en) Air conditioning apparatus
US3308805A (en) Heating and air conditioning apparatus
US2164718A (en) Heating and air conditioning system
US2013136A (en) Hot air furnace
US2385652A (en) Heating apparatus
US1687983A (en) Hot-air furnace
US1877223A (en) Method of humidifying air
GB1041223A (en) Improvements relating to air-warming installations
US2424927A (en) Air heating and humidifying apparatus
US1993539A (en) Apparatus for conditioning air
US2232347A (en) Humidifier
US1745401A (en) Water heater
US2190997A (en) Air heating apparatus
US2190998A (en) Air conditioning apparatus
US1925601A (en) Automatic humidity regulating mechanism for heating systems
US2157531A (en) Comfort cooling unit
US1986538A (en) Improved furnace construction
US2012547A (en) Air conditioning apparatus
US2178268A (en) Method and apparatus for domestic house heating