US2171917A - Combustion apparatus - Google Patents

Combustion apparatus Download PDF

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Publication number
US2171917A
US2171917A US134983A US13498337A US2171917A US 2171917 A US2171917 A US 2171917A US 134983 A US134983 A US 134983A US 13498337 A US13498337 A US 13498337A US 2171917 A US2171917 A US 2171917A
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inner casing
heat exchanger
air
openings
compartments
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US134983A
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Lin Martin De
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HOLLAND FURNACE CO
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HOLLAND FURNACE CO
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    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24HEATING; RANGES; VENTILATING
    • F24HFLUID HEATERS, e.g. WATER OR AIR HEATERS, HAVING HEAT-GENERATING MEANS, e.g. HEAT PUMPS, IN GENERAL
    • F24H3/00Air heaters
    • F24H3/02Air heaters with forced circulation
    • F24H3/06Air heaters with forced circulation the air being kept separate from the heating medium, e.g. using forced circulation of air over radiators
    • F24H3/065Air heaters with forced circulation the air being kept separate from the heating medium, e.g. using forced circulation of air over radiators using fluid fuel

Definitions

  • Figure 2 is a vertical sectional View of the apparatus taken on substantially the line 2 2 of Figure l;
  • Figure 3 is a horizontal sectional view taken on substantially the line 3 3 of Figure 1;
  • Figure 4 is a fragmentary elevational view taken on substantially the line 4 4 of Figure l;
  • Figure 5 is a fragmentary sectional view taken on substantially the line 5 5 of Figure 1;
  • Figure 6 is a fragmentary view taken on the line 6 6 of Figure 2;
  • Figure 7 is a fragmentary horizontal sectional view taken on substantially the line 1 1 of Figure l;
  • FIGS 8, 9, 10 and 11 are perspective views of the apparatus in various stages of assembly.
  • a supporting frame I0 a heat exchanger II mounted upon the supporting frame I0, an inner casing I2 enclosing the heat exchanger, an outer casing I3 enclosing the inner casing, circulating fan units Il', air filters 9, an oil burning unit I5, and an open topped primary combustion chamber I6 disposed within and spaced from the walls of heat exchanger Il.
  • the nozzle of oil burning unit I5 discharges into the chamber IB.
  • the heat exchanger II, the inner casing I2 and the outer casing I3 are constructed from standard sectional elements whereby the size thereof may be readily varied.
  • the filters 9 and fan units I4 are of a character whereby one or more may be used.
  • outer casing I3 is provided with a cold air inlet opening I0 adjacent the top thereof and immediately over the exhaust nues I1 and Il.
  • the outer casing may be provided with a plurality of smaller openings in its vertical walls as shown at Ila. Communication is provided between 5 the interior of outer casing Il and the intericry of inner casing I2 through means of a pair of openings 20 in the bottom wail ⁇ of the inner casing I2.
  • Each of the fan units I4 is operatively associated with one of the openings 20 I n the bottomof inner casing I2. They are of the axially intake and radial discharge Ftype whereby the cold 1f air is drawn into the outer casing i3 through inlet opening I9 and then forced' through inner casing I2 and out of outlet opening,2i. j'lIhus, ⁇ the air in the outer casing 'Il is under a vacuum and the airin the lnnerrcaslng i'2 is under pres- 20 sure. Consequently, there can be no loss of heat or combustion gases 'through outer casing I3.
  • the fans I4 are mounted upon a rotatable shaft 22 which is driven through a driving connection 2l by an electric motor 24.
  • the con- 25 nectlon between the discharge outlets of fans I4 and the openings 20 include a flexible tube Ila of canvas or the like (see Fig. 5).
  • the fan units I4 are housed within a compartment a0 defined by the bottom wall I2a of vertical casing I2, the vertical viframe members 8, the vertical walls 8 and 1, and the removable filter units 9.
  • Outer casing Il is provided with openings in its side walls affording access to the filter 35l units l (see Fig. 11). These openings are closed by removable panels.
  • Five filter units are shown, the two on each side of the apparatus being inclined from the vertical to ⁇ expose a larger surface area to the air traveling verti- 40 cally downwardly from opening I9. The direction of travel through the apparatus of the air to be heated is shown by the arrows in Figure 2. Thus, it will be seen that all of such air passes through the filters I. 45
  • the heat exchanger II is of novel construction. 55
  • the entire heat exchanger II is made up of a plurality of sectional compartments Il and I2 detachably connected to each other.
  • compartments II and I! are of generally ⁇ elliptical shape in horisontal cross-section
  • the openings 3l in compartments II provide a straight horizontal passageway for the products of combustion which is of substantially uniform height and width, the height being materially greater than the width.
  • Communication is provided for between the expansion chamber IIa and the economiser chamber IIb by corresponding restricted openings formed in the side wall o! adjacent compartments II and I2. Communication is provided between the compartments I! by cooperating restricted openings II formed in the adjacent ,side walls thereof. Communication is provided l' between the economizer chamber Ill) andthe exhaustiiuesilandllbyapairofrestricted openings It and I1 in the adjacent side wall of compartment 82.
  • Openings u and 3l are the same height as openings but of materially less width.
  • the 'size and location of all of the openings Il, Il. ll 'and 31 are such that a major portion of the side walls in which they are formed are directly exposed to the air circulated through inner casing I2.
  • these openings are arranged to form a serpentine passageway through the economizer chamber IIb. The air circulated through inner casing I2 passes between the convolutions of this passageway.
  • Each of the compartments Il and 32 isv provided with four ears ll.
  • the ears on adjacent compartments are formed with aligned openings for the reception oi' securing rods Il which together with the clamping nuts 4I at the opposite extremities thereof serve to detachably connect all of the compartments li and I2 together in operative relation.
  • Coil spring elements l! are shown as mounted upon one end of the rods Il and interposed between the compartment l2 and the adjacent clamping nut 4I.
  • the compartments are connected to each other in a manner to permit the natural expansion and contraction resulting from the changes in temperature produced within the heat exchanger I I.
  • the heat exchanger I I is mounted upon a supporting frame Il.
  • 'Ihe supporting frame I l consists of two spaced apart hor-L izontally extending parallel pipes IIb supported at their opposite ends by vertical pipes Ita.
  • Each pair oi vertical pipes Ila are connected to each other by a cross-support llc.
  • a rigid supporting frame for the heat exchanger II The rear end of the heat exs,171,o1v
  • the. heat exchanger II is not connected to the supporting frame in any w'ay. but is merely 4mounted upon the horizontally extending pipes IIb and held in position by gravity and the surrounding inner jacket I2. Consequently, the compartments 3i and I2 comprising the heat exchanger Il are free to expand and contract in a' horizontal direction longitudinally of the pipes IIb.
  • the ears Il at the top and bottom of the compartments 3i and 32 prevent horizontal movement of the heat exchanger in a lateral direction relative to the pipes IIb.
  • the opening Il in the end compartment ti (right hand side of Figures 1 and 3) is partially l closed by a plate 4I provided with a large rectangular opening.
  • a second plate or closure u is detachably connected to plate 43 by lugs a which hold it in position to close said opening.
  • Closure plate M is insulated, as shown, and is provided with an opening through which a conduit extends.
  • Primary combustion chamber Il is connected to the inner end of the conduit.
  • Burner Il is connected to the outer end of the conduit.
  • the plate 44, combustion chamber II, and burner Il comprise a unitary assembly which can be removed and installed as a unit.
  • Burner I I is supported by a bracket 45 carried by plate 44.
  • Auxiliary combustion supporting air is admitted toheat exchanger II through an opening in plate u with which is associated an adjustable closure 40 (see Iiig. 4).
  • the inner casing I! and the outer casing I3 are provided with openings in the front end thereof which are closed by the plates 4I and u. Oi' course, in this particular sone the inner casing I2 is not spaced from the heat exchanger II, and the outer casing Il is not spaced from the inner casing Il.. Plates 4I and ll vand burner IS-are enclosed within an auxiliary housing 41.
  • Exhaust iiues I1 and Il are shown as connected to a common chimney iiue 4I of uniform crosssectional area.
  • the upper exhaust iiue Il is providedwith a damper ll whereby to vary the cross-sectional area of that nue to provide for a uniform pressure in the two ilues I'I and I8. This is done in order to insure that the products of combustion passing through the two sections oi the heat exchanger will be distributed uniformly throughout the vertical extent of the passageway therethrough.
  • Combustion is initiated in the primary combustion chamber iCby the oil burner I5.
  • the combustion there initiated expands into the expansion section VIIa of heat exchanger II and the products of combustion 'then pass into the economizer section IIb and ilnally into the chimney ue 4l through the exhaust nues I1 and Il.
  • the expansion section provides a passageway for the products oi' combustion which is of uniform height and width.
  • the economizer sectionof the heat exchanger provides a eway for the products of combustion which is of uniform height and varying width.
  • Airisdrawnintotheoutercasing Itthrough the inlet opening I9 by the fans I4.
  • major portion of the air either passes over the outer surface of the inner casing I2 or over the outer surface of the exhaust nues I1 and I8, absorbing some heat therefrom.
  • the fans I4 force the air from outer casing I3 into inner casing I2 through the openings 20 and-out of the inner casing I2 through the outlet opening 2l.
  • the air passes between all of the compartments 3
  • the present invention provides a selfcontined combustion apparatus, so designed as to obtain the most efficient transfer of heat to the medium to be heated.
  • a device of the character described comprising a heat exchanger, an inner casing completely surrounding the heat exchanger having an inlet opening in its bottom wall and an outlet opening in its top wall, an air circulating compartment formed below the inner casing, said circulating compartment being defined in part by a series of filters constituting substantial continuations of a plurality of the side walls of said inner casing, an outer casing surrounding the inner casing and the circulating compartment, said outer casing having an inlet opening adjacent the top thereof, and a circulating unit located in said circulating compartment for drawing air into the outer casing and forcing it through the inner casing, communicationbeing provided between the outer casing and the inner casing solely through the filters forming side walls of the circulating compartment.

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  • 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 Supply (AREA)

Description

Sept. 5, 1939.
M. DE LIN `COMBUSTION APPARATUS Filed April 5, 1937 4 Sheets-Sheet l Sept. 5, 1939. M DE L|N 2,171,917
COMBUSTION APPARATUS Filed April 5, 1957 4 Sheets-Sheet 2 /N I/ EN TOR Nariz?? ZeZIZ' A TTORNE Y Sept. 5, 1939. M DE L|N 2,171,917
COMBUSTION APPARATUS Filed April 5, 1937 4 SheebS--Sheel'l 3 /NI/ENTOR A TTORNEV sept. 5,1939.
M. DE LIN COMBUSTION APPARATUS Filed April 5. 19257 4 Sheets-Sheet 4 /N VENTOR Mara?? elz'rg.
A RNE Patented Sept. 5, 1939 n UNITED STATES PATENT OFFICE OOHBUB'HON APPARATUS slm-tm ne un. um. una., nlmto nolland Furnace Company, Holland, lich., a corporation of Michigan An illustrative embodiment of the inventionis shown in the accompanying drawings, wherein- Figure 1 is a vertical sectional view of .combustion apparatus embodying the present invention, taken on substantially the line I I of Figure 8;
Figure 2 is a vertical sectional View of the apparatus taken on substantially the line 2 2 of Figure l; Figure 3 is a horizontal sectional view taken on substantially the line 3 3 of Figure 1;
Figure 4 is a fragmentary elevational view taken on substantially the line 4 4 of Figure l; Figure 5 is a fragmentary sectional view taken on substantially the line 5 5 of Figure 1;
Figure 6 is a fragmentary view taken on the line 6 6 of Figure 2;
Figure 7 is a fragmentary horizontal sectional view taken on substantially the line 1 1 of Figure l; and
Figures 8, 9, 10 and 11 are perspective views of the apparatus in various stages of assembly.
The apparatus illustrated in the accompanying drawings includes several major parts,
namely, a supporting frame I0, a heat exchanger II mounted upon the supporting frame I0, an inner casing I2 enclosing the heat exchanger, an outer casing I3 enclosing the inner casing, circulating fan units Il', air filters 9, an oil burning unit I5, and an open topped primary combustion chamber I6 disposed within and spaced from the walls of heat exchanger Il. The nozzle of oil burning unit I5 discharges into the chamber IB. The heat exchanger II, the inner casing I2 and the outer casing I3 are constructed from standard sectional elements whereby the size thereof may be readily varied. Likewise, the filters 9 and fan units I4 are of a character whereby one or more may be used.
The products of combustion formed in the heat exchanger Il are discharged through exhaust flues I1 and I8 extending through inner casing I2 and outer casing I3. Outer casing I3 is provided with a cold air inlet opening I0 adjacent the top thereof and immediately over the exhaust nues I1 and Il. As an alternative to the use of a single air inlet opening Il, the outer casing may be provided with a plurality of smaller openings in its vertical walls as shown at Ila. Communication is provided between 5 the interior of outer casing Il and the intericry of inner casing I2 through means of a pair of openings 20 in the bottom wail `of the inner casing I2. 'I'he inner casing I2 is p rovideti'withl an outlet opening 2| in its top wall gfor the dis- 10 charge oi' heated air. 1 j Each of the fan units I4 is operatively associated with one of the openings 20 I n the bottomof inner casing I2. They are of the axially intake and radial discharge Ftype whereby the cold 1f air is drawn into the outer casing i3 through inlet opening I9 and then forced' through inner casing I2 and out of outlet opening,2i. j'lIhus,` the air in the outer casing 'Il is under a vacuum and the airin the lnnerrcaslng i'2 is under pres- 20 sure. Consequently, there can be no loss of heat or combustion gases 'through outer casing I3.
The fans I4 are mounted upon a rotatable shaft 22 which is driven through a driving connection 2l by an electric motor 24. The con- 25 nectlon between the discharge outlets of fans I4 and the openings 20 include a flexible tube Ila of canvas or the like (see Fig. 5).
As best 'shown in Figures 2, 3, 'l andll, the fan units I4 are housed within a compartment a0 defined by the bottom wall I2a of vertical casing I2, the vertical viframe members 8, the vertical walls 8 and 1, and the removable filter units 9. Outer casing Il is provided with openings in its side walls affording access to the filter 35l units l (see Fig. 11). These openings are closed by removable panels. Five filter units are shown, the two on each side of the apparatus being inclined from the vertical to `expose a larger surface area to the air traveling verti- 40 cally downwardly from opening I9. The direction of travel through the apparatus of the air to be heated is shown by the arrows in Figure 2. Thus, it will be seen that all of such air passes through the filters I. 45
In order to control the direction of flow of the air passing from outer casing Il into inner casing I2 through openings 20, there are associateci with openings 2li adjustable vanes 30. These vanes distribute the air delivered to the 50 inner casing I2 by the fans I4 in such manner that the air will contact the maximum area of heat exchanger II in passing through the inner casing I2. e i
The heat exchanger II is of novel construction. 55
It includes expansion chamber IIa surrounding the primary combustion chamber Il and an economiser chamber IIb adjacent the exhaust nues I1 and Il. The entire heat exchanger II is made up of a plurality of sectional compartments Il and I2 detachably connected to each other.
'I'he several sectional compartments II formthe expansion chamber IIa and the compartments l2 form the economizer chamber IIb.
All of the compartments II and I! are of generally `elliptical shape in horisontal cross-section,
.and of substanially rectangular shape in vertical ures 1 and 3, the openings 3l in compartments II provide a straight horizontal passageway for the products of combustion which is of substantially uniform height and width, the height being materially greater than the width.
" Communication is provided for between the expansion chamber IIa and the economiser chamber IIb by corresponding restricted openings formed in the side wall o! adjacent compartments II and I2. Communication is provided between the compartments I! by cooperating restricted openings II formed in the adjacent ,side walls thereof. Communication is provided l' between the economizer chamber Ill) andthe exhaustiiuesilandllbyapairofrestricted openings It and I1 in the adjacent side wall of compartment 82.
Openings u and 3l are the same height as openings but of materially less width. The 'size and location of all of the openings Il, Il. ll 'and 31 are such that a major portion of the side walls in which they are formed are directly exposed to the air circulated through inner casing I2. As best shown in Figure 3, these openings are arranged to form a serpentine passageway through the economizer chamber IIb. The air circulated through inner casing I2 passes between the convolutions of this passageway.
Each of the compartments Il and 32 isv provided with four ears ll. The ears on adjacent compartments are formed with aligned openings for the reception oi' securing rods Il which together with the clamping nuts 4I at the opposite extremities thereof serve to detachably connect all of the compartments li and I2 together in operative relation. Coil spring elements l! are shown as mounted upon one end of the rods Il and interposed between the compartment l2 and the adjacent clamping nut 4I. Thus, the compartments are connected to each other in a manner to permit the natural expansion and contraction resulting from the changes in temperature produced within the heat exchanger I I.
As previously stated, the heat exchanger I I is mounted upon a supporting frame Il. 'Ihe supporting frame I l consists of two spaced apart hor-L izontally extending parallel pipes IIb supported at their opposite ends by vertical pipes Ita. Each pair oi vertical pipes Ila are connected to each other by a cross-support llc. Thus,there is provided a rigid supporting frame for the heat exchanger II. The rear end of the heat exs,171,o1v
jchangerisanchoredtothesupportingframeby saddles I, which have an interlocking engagement with the frame and .the lower edge of one of the compartments I! (see Fig. 6). Except for the two saddles I. the. heat exchanger II is not connected to the supporting frame in any w'ay. but is merely 4mounted upon the horizontally extending pipes IIb and held in position by gravity and the surrounding inner jacket I2. Consequently, the compartments 3i and I2 comprising the heat exchanger Il are free to expand and contract in a' horizontal direction longitudinally of the pipes IIb. The ears Il at the top and bottom of the compartments 3i and 32 prevent horizontal movement of the heat exchanger in a lateral direction relative to the pipes IIb.
The opening Il in the end compartment ti (right hand side of Figures 1 and 3) is partially l closed by a plate 4I provided with a large rectangular opening. A second plate or closure u is detachably connected to plate 43 by lugs a which hold it in position to close said opening.
Closure plate M is insulated, as shown, and is provided with an opening through which a conduit extends. Primary combustion chamber Il is connected to the inner end of the conduit. Burner Il is connected to the outer end of the conduit. The plate 44, combustion chamber II, and burner Il, comprise a unitary assembly which can be removed and installed as a unit. Burner I I is supported by a bracket 45 carried by plate 44. Auxiliary combustion supporting air is admitted toheat exchanger II through an opening in plate u with which is associated an adjustable closure 40 (see Iiig. 4).
As clearly shown in Figures 1 and 3, the inner casing I! and the outer casing I3 are provided with openings in the front end thereof which are closed by the plates 4I and u. Oi' course, in this particular sone the inner casing I2 is not spaced from the heat exchanger II, and the outer casing Il is not spaced from the inner casing Il.. Plates 4I and ll vand burner IS-are enclosed within an auxiliary housing 41.
Exhaust iiues I1 and Il are shown as connected to a common chimney iiue 4I of uniform crosssectional area. The upper exhaust iiue Il is providedwith a damper ll whereby to vary the cross-sectional area of that nue to provide for a uniform pressure in the two ilues I'I and I8. This is done in order to insure that the products of combustion passing through the two sections oi the heat exchanger will be distributed uniformly throughout the vertical extent of the passageway therethrough.
The operation of the apparatus herein illustrated and described is as follows:
Combustion is initiated in the primary combustion chamber iCby the oil burner I5. The combustion there initiated expands into the expansion section VIIa of heat exchanger II and the products of combustion 'then pass into the economizer section IIb and ilnally into the chimney ue 4l through the exhaust nues I1 and Il. The expansion section provides a passageway for the products oi' combustion which is of uniform height and width. The economizer sectionof the heat exchanger provides a eway for the products of combustion which is of uniform height and varying width. The use of the two exhaust iiues Il and il assures a proper vertical distribution of the products oi' combustion whereby the heat thereof is distributed to all portions of the sectional compartments Il and 32.
Airisdrawnintotheoutercasing Itthrough the inlet opening I9 by the fans I4. In traveling between the inlet opening I8 and the fans I4 a. major portion of the air either passes over the outer surface of the inner casing I2 or over the outer surface of the exhaust nues I1 and I8, absorbing some heat therefrom. The fans I4 force the air from outer casing I3 into inner casing I2 through the openings 20 and-out of the inner casing I2 through the outlet opening 2l. In traveling through the inner casing I2 the air passes between all of the compartments 3| and I2, and is directly exposed to contact with a substantial portion of the side walls of compartments 3l and a major portion of the side walls of. compartments 32. All together, ve sides of the heat exchanger are directly exposed to the air passing through inner casing I2. In this manner, a very ei'iicient transfer of heat from the heat exchanger to the air to be heated is effected. In traveling from the outer casing I3 to the inner casing I2, all of the air to be heated passes through the filters 9.
From the foregoing description it will be apparent that the present invention provides a selfcontined combustion apparatus, so designed as to obtain the most efficient transfer of heat to the medium to be heated.
While, as previously indicated, the invention resides in the construction and arrangement of the apparatus herein illustrated and described, it will be readily apparent to those skilled in this art that the invention is not limited to such apparatus butmay be embodied in various other forms of apparatus. The scope of the invention is indicated by the appended claims.
I claim:
1. A device of the character described comprising a heat exchanger, an inner casing completely surrounding the heat exchanger having an inlet opening in its bottom wall and an outlet opening in its top wall, an air circulating compartment formed below the inner casing, said circulating compartment being defined in part by a series of filters constituting substantial continuations of a plurality of the side walls of said inner casing, an outer casing surrounding the inner casing and the circulating compartment, said outer casing having an inlet opening adjacent the top thereof, and a circulating unit located in said circulating compartment for drawing air into the outer casing and forcing it through the inner casing, communicationbeing provided between the outer casing and the inner casing solely through the filters forming side walls of the circulating compartment.
2. A device of the character defined in claim 1 wherein the filters are arranged at an inclination to the side walls of the inner casing whereby to expose a larger area thereof to the air passing from the outer casing into the circulating compartment.
3. A device of the character deilned in claim 1 wherein said filters constitute a substantial continuation of at least two of the side walls of the inner casing.
MARTIN DE LIN.
US134983A 1937-04-05 1937-04-05 Combustion apparatus Expired - Lifetime US2171917A (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2581145A (en) * 1947-09-05 1952-01-01 Bone Tool & Gauge Company Oil burning hot-air furnace

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2581145A (en) * 1947-09-05 1952-01-01 Bone Tool & Gauge Company Oil burning hot-air furnace

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