CA1109440A - Heating system - Google Patents
Heating systemInfo
- Publication number
- CA1109440A CA1109440A CA324,351A CA324351A CA1109440A CA 1109440 A CA1109440 A CA 1109440A CA 324351 A CA324351 A CA 324351A CA 1109440 A CA1109440 A CA 1109440A
- Authority
- CA
- Canada
- Prior art keywords
- heating
- coil
- compartment
- burner
- holding
- 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
Links
Landscapes
- General Induction Heating (AREA)
Abstract
ABSTRACT OF DISCLOSURE
A heating system comprises serially connected heating and holding coils connected in a closed heating liquid circulating circuit with a collector coil at the space to be heated. The heating and holding coils are disposed in a compartment wherein both are subject to direct heating by one or more gas burners, and flue gas is drawn through the compartment in heat exchange relation with the holding coil before being exhausted.
A heating system comprises serially connected heating and holding coils connected in a closed heating liquid circulating circuit with a collector coil at the space to be heated. The heating and holding coils are disposed in a compartment wherein both are subject to direct heating by one or more gas burners, and flue gas is drawn through the compartment in heat exchange relation with the holding coil before being exhausted.
Description
~1~9440 This invention relates to heating systems that burn gas and particularly to closed circuit systems of this type having special arrangements for heating a liquid to be eireu-lated.
The invention contemplates a highly efficient gas burner energized system wherein a heating liquid is passed through heating and holding coils disposed in special heat exchange relationship with one or more gas burners whereby heat derived by conduction and radiation from the burners and by passage of the flue gases through the holding coil prior to exhaust is cumulatively utilized to heat the liquid, and this is a major objeet of the invention.
The invention further contemplates passing the liquid so heated through a closed circuit ineluding a heat collector coil assembly disposed to selectively impart heat to space to be heated, together with associated controls for preheating the liquid in the circuit to a desired temperature and auto-matically acitvating components of the system to perform their sequential functions, and this is a further object of the invention.
More detailed objects of the invention include insulated heating compartment construction embodying special arrangements of serially connected heating and holding coils relative to the burner or burners, and an associated perforated eompartment wall strueture whereby flue gases from the burners may be drawn in heat exehange relation through at least the holding coil before exhaust through the perforated walls.
Further objects of the iDvention will appear in con-nection with the appended elaims and the annexed drawings.
The present invention provides a heating system having communicating means leading to space to be heated com-C prising means defining a closed compartment with at least one ~1~9440 gas burner assembly disposed in the compartment, said burner assembly having a high heat conducting and radiating flue gas discharge wall facing the interior of said compartment said wall containing multiple perforations, a heating coil in said compartment at least in closely adjacent radiant heat exchange with said wall and extending planar to and substantially the length of said wall, a holding coil in said compartment posi-tioned separate from an inwardly of said heating coil and con-nected at one end to one end of said heating coil, a heat col-lector coil disposed in an enclosure in said space to be heatedconnected to said communicating means, means for forcing air to be heated over said heat collector ooil into said ducting, a heating liquid supply conduit connecting the other end of said holding coil to one end of said heat collector coil, a heating liquid return conduit connecting the other end of said heat collector coil to the other end of said heating coil, thus providing a closed circuit between and including said -coils containing a heating liquid, a motor driven pump in said supply line adapted when actuated to force liquid from said holding coil toward said heat conduit, means responsive to a drop in the temperature in said heat collector coil below a predetermined lower value for energizing said burner and actuating the pump to circulate heating fluid through said circuit and for stopping such circulation and inactivating the burner when that temperature raises to a predetermined higher value, said heating and holding coils being subject to direct heating from said burner and there being means at said compartment for ~orcing hot flue gases from said burner through said holding coil before exhaust.
In another embodiment, the heating system comprises means defining a closed compartment, at least one gas burner assembly disposed in said compartment, said burner assembly C
~ 9440 having a high heat conducting and radiating flue gas discharge wall facing the interior of said compartment, said wall con-taining multiple perforations, a heating coil in said compart-ment at least in closely adjacent radiant heat exchange with said wall and extending planar to and substantially the length of said wall, a holding coil in said compartment positioned separate from and inwardly of said heating coil and connected at one end to one end of said heating coil, said heating and holding coils being subject to direct heating from said burner, a heating liquid outlet conduit connected to the other end of said holding coil, a heating liquid inlet conduit connected to the other end of said heating coil, pump means for forcing liquid from said holding coil through said liquid outlet con-duit, and means for forcing hot flue gas from said burner through said holding coil.
In drawings which illustrate the embodiments of the invention, Fig, 1 is a diagrammatic view illustrating the heating - system of the invention according to a preferred embodiment;
and Fig, 2 is a partly diagrammatic view showing preferred physical relationships of the parts of the heat generating portion of the system.
Referring now to the drawings, the illustrated system shown in Fig. 1 comprises two burner assemblies 11 and 12 dis-posed in a compartment 13 at opposite sides of a holding coil 14, with heating coils 15 and 16 serially connected to the holding coil and disposed between the respective burners and the holding coil.
In a preferred structure such as shown in Fig. 2, holding coil 14 is composed of copper or other suitable metal tubing carrying thin heat conductive fins; and the respective ,. ll~g4~0 burner assemblies are gas burners having hign heat conductive perforated ceramic walls 17 and 18 facing into the compartment, with heating coils 15 and 16 being sinuous lengths of copper or like metal tubing preferably mounted directly on the per-forated burner walls or immediately adjacent thereto.
As shown, adjacent ends of heating coils 15 and 16 are connected to one end of the holding coil 14, The other end of holding coil 14 is connected to a heating liquid supply line 19 connected through a motor driven pump 21 to one end of a heat collector coil 22, The other ends of heating coils 15 and 16 are connected to a heating liquid return line 24 connected to the other end of the heat collector coil, The heating liquid may be water or any other liquid capable of being heated with-out deterioration of the system components, The foregoing coils and lines constitute a closed circuit (can be a closed circuit of an open circuit with expan-sion tank mounted outside combustion chamber on hot line l9) that is filled with a heating liquid, The volumetric capacity of holding coil 14 is preferably about equal to that of collec-tor coil 22, An aquastat or equivalent heat sensitive device 25in the circuit in ~r adjacent heat collector coil 22 is con-nected to a control device 20 for simultaneous actuation or deactivation of pump 21 and the burners, as will appear~
Heat collector coil 22 as shown may be disposed in an enclosure 26 in the building containing a motor driven fan 27 and connected to the conventional hot air ducting 28 leading ; to the space or spaces to be heated, A thermostat 29 in that space is connected to selectively operate the fan to force air through the heat collector coil as will appear, Preferably lines 19 and 24 are heavily covered with heat insulation where they extend between compartment 13 and . enclosure 26, That is true whether the compartment 13 is )94~0 ' located outside the building as shown, or within the same building which is an important phase of the invention that decreases the extent of heat insulation required for compart-ment 13.
The disposition and heating of the heating and holding coils is a very important phase of the invention, As disclosed above the heating coils 15 and 16 may be in direct heat con-ductive contact or at least in closely adjacent radiant heat exchange with the cer~mic walls 17 and 18 of the burners, both the heating coils and holding coil 14-being exposed to direct radiant heat from the perforated burner walls.
Additionally it will be noted that the inner top wall 31, inner bottom wall 32 and the inner front and rear walls 33 ; (rear wall only shown in Fig. 1) that partly bound the compart-ment 13 are perforated stainless steel or other rigid metal j~ plates. The compartment inner side walls 35 and 36 on which burner assemblies 11 and 12 are mounted are preferably imper-forate stainless steel plates. The outer top wall 37, outer bottom wall 38 and outer front and rear walls (not shown) are also imperforate stainless steel plates. All of these imper-forate plates are joined at their edges so that the outer walls define a complete outer jacket enclosure that is imperforate except for flue gas outlet 39, combustion air ~nlets such as the louvers indicated at 41 and 42, arrangements for introduc-ing the gas conduits to gas burners 43 and 44 and electrical wires for spark discharge igniters 45 and 46 of the burners.
Fig. 1 shows an exhaust fan assembly 50, which when idle closes and seals off flue outlet 39, and the motor of fan 50 is suitably connected to operate the fan to withdraw flue gas only when the gas burners are energized. When fan 50 rotates the products of combustion including the flue gas are pulled into compartment 13 through the perforations in ~ 9~4(3 burner walls 17 and 18 and circu]ated through the compartment in heat exchange relation with the finned holding coil 14 before being drawn out through the perforated metal walls around the compartment. Preferably a layer 51 of asbestos or like heat insulation, lines all of the imperforate plates and there is a small space between that layer and the adjacent perforated plates providing passage so that the flue gas drawn through the perforated plates travels through that passage to exit at 39.
As shown in chain lines in Fig. 1 the entire compart-ment structure is disposed in a heavily insulated enclosure, and may be located externally of the building wall W. Alter-natively it may be disposed internally of the building wherein ; the collector coil is mounted In either event the liquid heating portion of the system is essentially a separate u~it capable of being factory made and shipped to a point of use ; for installation in coaction with existing ducting in a building.
The term coil is meant to include substantially all passage forming structures for equivalently circulating the heating liquid. While a two burner system is specifically ; disclosed, the invention contemplates a system using one burner and one heating coil associated with the holding coil.
The foregoing structure and mode of operation has been found to be unexpectedly efficient. In an existing system a building containing about 5400 square feet of floor space has been heated successfully in the rigorous climate of South Dakota. The heating liquid was preheated to about 180F and the pump and burners were activated, when the tempera-ture reached about 145 at the collector coil and cut off when the temperature in there again reached about 180.
The remarkable efficiency of about at least 35 to 50 per cent more efficiency for a properly installed and operated ~' h~ -6-system is claimed.
The invention may be embodied in other specific forms without departing from the spirit or essential character-istics thereof. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, - the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.
. .
.
, .
The invention contemplates a highly efficient gas burner energized system wherein a heating liquid is passed through heating and holding coils disposed in special heat exchange relationship with one or more gas burners whereby heat derived by conduction and radiation from the burners and by passage of the flue gases through the holding coil prior to exhaust is cumulatively utilized to heat the liquid, and this is a major objeet of the invention.
The invention further contemplates passing the liquid so heated through a closed circuit ineluding a heat collector coil assembly disposed to selectively impart heat to space to be heated, together with associated controls for preheating the liquid in the circuit to a desired temperature and auto-matically acitvating components of the system to perform their sequential functions, and this is a further object of the invention.
More detailed objects of the invention include insulated heating compartment construction embodying special arrangements of serially connected heating and holding coils relative to the burner or burners, and an associated perforated eompartment wall strueture whereby flue gases from the burners may be drawn in heat exehange relation through at least the holding coil before exhaust through the perforated walls.
Further objects of the iDvention will appear in con-nection with the appended elaims and the annexed drawings.
The present invention provides a heating system having communicating means leading to space to be heated com-C prising means defining a closed compartment with at least one ~1~9440 gas burner assembly disposed in the compartment, said burner assembly having a high heat conducting and radiating flue gas discharge wall facing the interior of said compartment said wall containing multiple perforations, a heating coil in said compartment at least in closely adjacent radiant heat exchange with said wall and extending planar to and substantially the length of said wall, a holding coil in said compartment posi-tioned separate from an inwardly of said heating coil and con-nected at one end to one end of said heating coil, a heat col-lector coil disposed in an enclosure in said space to be heatedconnected to said communicating means, means for forcing air to be heated over said heat collector ooil into said ducting, a heating liquid supply conduit connecting the other end of said holding coil to one end of said heat collector coil, a heating liquid return conduit connecting the other end of said heat collector coil to the other end of said heating coil, thus providing a closed circuit between and including said -coils containing a heating liquid, a motor driven pump in said supply line adapted when actuated to force liquid from said holding coil toward said heat conduit, means responsive to a drop in the temperature in said heat collector coil below a predetermined lower value for energizing said burner and actuating the pump to circulate heating fluid through said circuit and for stopping such circulation and inactivating the burner when that temperature raises to a predetermined higher value, said heating and holding coils being subject to direct heating from said burner and there being means at said compartment for ~orcing hot flue gases from said burner through said holding coil before exhaust.
In another embodiment, the heating system comprises means defining a closed compartment, at least one gas burner assembly disposed in said compartment, said burner assembly C
~ 9440 having a high heat conducting and radiating flue gas discharge wall facing the interior of said compartment, said wall con-taining multiple perforations, a heating coil in said compart-ment at least in closely adjacent radiant heat exchange with said wall and extending planar to and substantially the length of said wall, a holding coil in said compartment positioned separate from and inwardly of said heating coil and connected at one end to one end of said heating coil, said heating and holding coils being subject to direct heating from said burner, a heating liquid outlet conduit connected to the other end of said holding coil, a heating liquid inlet conduit connected to the other end of said heating coil, pump means for forcing liquid from said holding coil through said liquid outlet con-duit, and means for forcing hot flue gas from said burner through said holding coil.
In drawings which illustrate the embodiments of the invention, Fig, 1 is a diagrammatic view illustrating the heating - system of the invention according to a preferred embodiment;
and Fig, 2 is a partly diagrammatic view showing preferred physical relationships of the parts of the heat generating portion of the system.
Referring now to the drawings, the illustrated system shown in Fig. 1 comprises two burner assemblies 11 and 12 dis-posed in a compartment 13 at opposite sides of a holding coil 14, with heating coils 15 and 16 serially connected to the holding coil and disposed between the respective burners and the holding coil.
In a preferred structure such as shown in Fig. 2, holding coil 14 is composed of copper or other suitable metal tubing carrying thin heat conductive fins; and the respective ,. ll~g4~0 burner assemblies are gas burners having hign heat conductive perforated ceramic walls 17 and 18 facing into the compartment, with heating coils 15 and 16 being sinuous lengths of copper or like metal tubing preferably mounted directly on the per-forated burner walls or immediately adjacent thereto.
As shown, adjacent ends of heating coils 15 and 16 are connected to one end of the holding coil 14, The other end of holding coil 14 is connected to a heating liquid supply line 19 connected through a motor driven pump 21 to one end of a heat collector coil 22, The other ends of heating coils 15 and 16 are connected to a heating liquid return line 24 connected to the other end of the heat collector coil, The heating liquid may be water or any other liquid capable of being heated with-out deterioration of the system components, The foregoing coils and lines constitute a closed circuit (can be a closed circuit of an open circuit with expan-sion tank mounted outside combustion chamber on hot line l9) that is filled with a heating liquid, The volumetric capacity of holding coil 14 is preferably about equal to that of collec-tor coil 22, An aquastat or equivalent heat sensitive device 25in the circuit in ~r adjacent heat collector coil 22 is con-nected to a control device 20 for simultaneous actuation or deactivation of pump 21 and the burners, as will appear~
Heat collector coil 22 as shown may be disposed in an enclosure 26 in the building containing a motor driven fan 27 and connected to the conventional hot air ducting 28 leading ; to the space or spaces to be heated, A thermostat 29 in that space is connected to selectively operate the fan to force air through the heat collector coil as will appear, Preferably lines 19 and 24 are heavily covered with heat insulation where they extend between compartment 13 and . enclosure 26, That is true whether the compartment 13 is )94~0 ' located outside the building as shown, or within the same building which is an important phase of the invention that decreases the extent of heat insulation required for compart-ment 13.
The disposition and heating of the heating and holding coils is a very important phase of the invention, As disclosed above the heating coils 15 and 16 may be in direct heat con-ductive contact or at least in closely adjacent radiant heat exchange with the cer~mic walls 17 and 18 of the burners, both the heating coils and holding coil 14-being exposed to direct radiant heat from the perforated burner walls.
Additionally it will be noted that the inner top wall 31, inner bottom wall 32 and the inner front and rear walls 33 ; (rear wall only shown in Fig. 1) that partly bound the compart-ment 13 are perforated stainless steel or other rigid metal j~ plates. The compartment inner side walls 35 and 36 on which burner assemblies 11 and 12 are mounted are preferably imper-forate stainless steel plates. The outer top wall 37, outer bottom wall 38 and outer front and rear walls (not shown) are also imperforate stainless steel plates. All of these imper-forate plates are joined at their edges so that the outer walls define a complete outer jacket enclosure that is imperforate except for flue gas outlet 39, combustion air ~nlets such as the louvers indicated at 41 and 42, arrangements for introduc-ing the gas conduits to gas burners 43 and 44 and electrical wires for spark discharge igniters 45 and 46 of the burners.
Fig. 1 shows an exhaust fan assembly 50, which when idle closes and seals off flue outlet 39, and the motor of fan 50 is suitably connected to operate the fan to withdraw flue gas only when the gas burners are energized. When fan 50 rotates the products of combustion including the flue gas are pulled into compartment 13 through the perforations in ~ 9~4(3 burner walls 17 and 18 and circu]ated through the compartment in heat exchange relation with the finned holding coil 14 before being drawn out through the perforated metal walls around the compartment. Preferably a layer 51 of asbestos or like heat insulation, lines all of the imperforate plates and there is a small space between that layer and the adjacent perforated plates providing passage so that the flue gas drawn through the perforated plates travels through that passage to exit at 39.
As shown in chain lines in Fig. 1 the entire compart-ment structure is disposed in a heavily insulated enclosure, and may be located externally of the building wall W. Alter-natively it may be disposed internally of the building wherein ; the collector coil is mounted In either event the liquid heating portion of the system is essentially a separate u~it capable of being factory made and shipped to a point of use ; for installation in coaction with existing ducting in a building.
The term coil is meant to include substantially all passage forming structures for equivalently circulating the heating liquid. While a two burner system is specifically ; disclosed, the invention contemplates a system using one burner and one heating coil associated with the holding coil.
The foregoing structure and mode of operation has been found to be unexpectedly efficient. In an existing system a building containing about 5400 square feet of floor space has been heated successfully in the rigorous climate of South Dakota. The heating liquid was preheated to about 180F and the pump and burners were activated, when the tempera-ture reached about 145 at the collector coil and cut off when the temperature in there again reached about 180.
The remarkable efficiency of about at least 35 to 50 per cent more efficiency for a properly installed and operated ~' h~ -6-system is claimed.
The invention may be embodied in other specific forms without departing from the spirit or essential character-istics thereof. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, - the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.
. .
.
, .
Claims (16)
1. A heating system having communicating means leading to space to be heated comprising means defining a closed compart-ment with at least one gas burner assembly disposed in the com-partment, said burner assembly having a high heat conducting and radiating flue gas discharge wall facing the interior of said compartment said wall containing multiple perforations, a heating coil in said compartment at least in closely adjacent radiant heat exchange with said wall and extending planar to and substantially the length of said wall, a holding coil in said compartment posi-tioned separate from an inwardly of said heating coil and connec-ted at one end to one end of said heating coil, a heat collector coil disposed in an enclosure in said space to be heated connected to said communicating means, means for forcing air to be heated over said heat collector coil into said ducting, a heating liquid supply conduit connecting the other end of said holding coil to one end of said heat collector coil, a heating liquid return con-duit connecting the other end of said heat collector coil to the other end of said heating coil, thus providing a closed circuit between and including said coils containing a heating liquid, a motor driven pump in said supply line adapted when actuated to force liquid from said holding coil toward said heat conduit, means responsive to a drop in the temperature in said heat collec-tor coil below a predetermined lower value for energizing said burner and actuating the pump to circulate heating fluid through said circuit and for stopping such circulation and inactivating the burner when that temperature raises to a predetermined higher value, said heating and holding coils being subject to direct heating from said burner and there being means at said compartment for forcing hot flue gases from said burner through said holding coil before exhaust.
2. In the heating system defined in claim 1, there being two of said burner assemblies in said compartment at oppo-site sides of said holding coil, and there being a heating coil between each burner assembly and the holding coil.
3. In the heating system defined in claim 2, adjacent ends of said heating coils being connected to said one end of the holding coil, and the other ends of said heating coils being con-nected to said return line.
4. In the heating system defined in claim 1, said means for forcing hot flue gas through said holding coil comprising side walls of said compartment formed with a plurality of perfo-rations and passage means behind said side walls leading to a flue exhaust device.
5. The heating system defined in claim 1, wherein said compartment is outside the space to be heated.
6. The heating system defined in claim 1, wherein said compartment is inside the space to be heated.
7. In the heating system defined in claim 6, means for actuating said burner and pump for preheating the liquid in said circuit to be predetermined value, and there being means respon-sive to the temperature in said space for activating said means for forcing air through the collector coil.
8. In the heating system defined in claim 1, said heat-ing coil being mounted in direct heat conductive relation upon said perforated burner wall.
9. In the heating system defined in claim 1, said heat-ing coil being mounted immediately adjacent said perforated burner wall.
10. In the heating system defined in claim 1, said per-forated burner wall being ceramic.
11, In the heating system defined in claim 1, said hold-ing coil and heat collector coils having substantially equal volu-metric capacities.
12. A heating system as defined in claim 1 wherein the heating coil is in the form of a sinuous length of metal tubing.
13. A heating system comprising means defining a closed compartment, at least one gas burner assembly disposed in said compartment, said burner assembly having a high heat conducting and radiating flue gas discharge wall facing the interior of said compartment, said wall containing multiple perforations, a heating coil in said compartment at least in closely adjacent radiant heat exchange with said wall and extending planar to and substan-tially the length of said wall, a holding coil in said compartment positioned separate from and inwardly of said heating coil and connected at one end to one end of said heating coil, said heating and holding coils being subject to direct heating from said burner, a heating liquid outlet conduit connected to the other end of said holding coil, a heating liquid inlet conduit connected to the other end of said heating coil, pump means for forcing liquid from said holding coil through said liquid outlet conduit, and means for forcing hot flue gas from said burner through said holding coil.
14. In the heating system defined in claim 12, there being two of said burner assemblies in said compartment at oppo-site sides of said holding coil, and there being a heating coil between each burner assembly and the holding coil.
15. In the heating system defined in claim 13, adjacent ends of said heating coils being connected to said one end of the holding coil, and the other ends of said heating coils being con-nected to said heating liquid inlet conduit.
16. In the heating system defined in claim 12, said means for forcing hot flue gas through said holding coil compri-sing side walls of said compartment formed with a plurality of perforations and passage means behind said side walls leading to a flue exhaust device.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA324,351A CA1109440A (en) | 1979-03-28 | 1979-03-28 | Heating system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA324,351A CA1109440A (en) | 1979-03-28 | 1979-03-28 | Heating system |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1109440A true CA1109440A (en) | 1981-09-22 |
Family
ID=4113853
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA324,351A Expired CA1109440A (en) | 1979-03-28 | 1979-03-28 | Heating system |
Country Status (1)
| Country | Link |
|---|---|
| CA (1) | CA1109440A (en) |
-
1979
- 1979-03-28 CA CA324,351A patent/CA1109440A/en not_active Expired
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US4401261A (en) | Flue gas heat recovery apparatus | |
| US4406402A (en) | Flue heat recovery system | |
| US5944090A (en) | Heat exchanger for furnace flue | |
| EP0004058B1 (en) | Heat storage device | |
| RU2138740C1 (en) | Method of and device for heating of room by pipe with electrically heated water | |
| CA2286040C (en) | Heaters | |
| US4558689A (en) | Combustion gas heat recovery apparatus | |
| EP0354334B1 (en) | Integrated apparatus for producing warm water | |
| US4436079A (en) | Fireplace for heating indoor spaces and water for sanitary use | |
| US4147301A (en) | Heating system | |
| US5299278A (en) | Forced air circulation electric convection space heating system utilizing heated air discharge to preheat air to be heated | |
| US4066210A (en) | Chimney heat reclaimer | |
| US4132263A (en) | Combined household heating and cooling unit for air and water | |
| US4149673A (en) | Self-pumping water boiler system | |
| CA1109440A (en) | Heating system | |
| KR101670334B1 (en) | Flat stone type residential heating system with air circulation | |
| RU2095695C1 (en) | Gas-fired furnace of complete combustion | |
| GB2116299A (en) | A water heating system | |
| US4158386A (en) | Self-pumping water boiler system | |
| US20070062935A1 (en) | A microwave heating system for conditioning air in a space by heating the air to change its temperature | |
| US4947930A (en) | Heat bonnet for heat pump | |
| CA1107702A (en) | Heating unit for hot water room heating systems | |
| US2241303A (en) | Hot-air furnace | |
| US20240175585A1 (en) | Stationary infrared radiator | |
| CA1187300A (en) | Heat exchanger coil |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| MKEX | Expiry |