Title:
FORCED CIRCULATION GAS WATER HEATER
United States Patent 3627202
Abstract:
A gas valve for the burner of a water heater is L-shaped with valves in each branch of the L. Push rods, positioned at right angles to each other, respectively operate the valves. One rod is actuated by an electromagnet and the other by a fluid pressure responsive diaphragm connected to a venturi. The venturi is in a water circuit that includes the heater, two temperature-limiting thermostats, a radiator and a circulating pump. An electrical circuit has two branches; one of which includes a switch controlled by one thermostat and the circulating pump motor; and the other of which includes switches controlled by both thermostats and the electromagnet.
US Patent References:
Gas-heated continuous-flow heater for hot-water circulation heating
Mobus et al. - May 1968 - 3383042
Gas-heated continuous-flow heater for hot-water circulation heating
Mobus et al. - May 1968 - 3383042
Application Number:
05/011125
Publication Date:
12/14/1971
Filing Date:
02/13/1970
View Patent Images:
Export Citation:
Assignee:
Joh. Vaillant KG (Remscheid, DT)
Primary Class:
Other Classes:
237/8D, 236/21R, 236/25R
International Classes:
F23N1/08; F24D3/02
Field of Search:
237/8
Primary Examiner:
Michael, Edward J.
Claims:
I claim
1. A hot water heating system including:
2. A hot water heating system as set forth in claim 1, wherein said two branches of said passage are at right angles to each other and the two valves are at right angles to each other, and the push rods are at right angles to their respective valves.
3. A hot water heating system as set forth in claim 2, wherein said one valve is normally biased in the closing direction of that valve and said fluid pressure responsive diaphragm-actuating means comprises:
4. A hot water heating system as set forth in claim 1, wherein said one valve is normally biased in the closing direction of that valve and said fluid pressure responsive diaphragm-actuating means comprises:
1. A hot water heating system including:
2. A hot water heating system as set forth in claim 1, wherein said two branches of said passage are at right angles to each other and the two valves are at right angles to each other, and the push rods are at right angles to their respective valves.
3. A hot water heating system as set forth in claim 2, wherein said one valve is normally biased in the closing direction of that valve and said fluid pressure responsive diaphragm-actuating means comprises:
4. A hot water heating system as set forth in claim 1, wherein said one valve is normally biased in the closing direction of that valve and said fluid pressure responsive diaphragm-actuating means comprises:
Description:
BACKGROUND AND SUMMARY OF THE INVENTION
The invention relates to a forced circulation gas water heater for operating a hot water heating system and comprising: a gas fitting in the gas path to the burner, which fitting has an L-shaped gas passage with a gas valve in each branch of the gas passage, each of which valves are a plate valve and are operated by a push rod, the push rods of the two gas valves being disposed in cruciform pattern relative to each other; a diaphragm-actuating member adapted to respond to the flow pressure in the circulating water path operatively associated with the push rod of one of said gas valves; a magnet whose armature is operatively associated with the push rod of the other gas valve; and a temperature-limiting control which can be actuated by a thermostat which responds to excess temperature.
A requirement for forced circulation gas water heaters is to have a gas safety valve, controlled by a temperature-limiting device, in addition to the gas valve which is controlled by the room thermostat and feed thermostat as well as by the flame monitor.
In forced circulation water-heating systems with a thermoelectric ignition safety device, the temperature-limiting switch is connected in the thermostat circuit so that the limiting switch interrupts the thermostat circuit in the event of excess temperature thus causing the ignition safety valve to close. However, an ignition safety valve of the kind heretofore described is not provided in apparatus having electronic flame monitoring for the burner. Accordingly, such apparatus requires an electrically controllable gas safety valve which is governed by the temperature-limiting device.
It has already been proposed for the temperature-limiting device switch, taking the form of an electric switch which opens with rising temperature, to be connected in circuit of the circulating pump, which pump in turn governs a low water safety valve via a diaphragm-actuating member responding to the closing pressure in the water-circulating path.
The prior art also discloses a system in which a gas fitting with an L-shaped gas passage is provided in the gas path to the burner. One gas valve each, constructed as plate valve, is provided in each branch of the L-shaped gas passage. The gas valve in the horizontal branch is the ignition safety valve which may be pushed open by means of a horizontally disposed push rod actuated by a manually operated pushbutton. A gas valve, which can be operated by an electromagnet via a vertically disposed push rod, is positioned in the vertical branch of the gas passage. The room thermostat and feed thermostat, as well as a switch contact operated by a diaphragm-actuating element which responds to the flow pressure in the water circulation path is connected in the circuit of the electromagnet.
It is an object of the invention to provide a forced circulation gas water heater of the kind mentioned heretofore which is as simple as possible and to construct it from a minimum number of parts.
It is a further object of the invention to provide a forced circulation gas water heater in which the flame is monitored by an electronic flame monitor and in which a gas valve is provided which is controlled by the temperature-limiting device and is independent of the flame monitor.
According to the invention this is achieved in that the diaphragm-actuating element acts directly on the horizontally disposed valve push rod of the fitting and the temperature limiter is connected in the circuit of the water-circulating pump; the ionization apparatus (flame monitor) controls the circuit of the magnet controlling the actuation of the vertically disposed push rod of the gas valve operated by the magnet.
DESCRIPTION OF THE DRAWING
The drawing illustrates diagrammatically a system embodying the invention with the electrical, but not the gas, circuit in "operating" position.
DESCRIPTION OF SPECIFIC EMBODIMENT
The following disclosure is offered for public dissemination in return for the grant of a patent. Although it is detailed to ensure adequacy and aid understanding, this is not intended to prejudice that purpose of a patent which is to cover each new inventive concept therein no mater how others may later disguise it by variations in form or additions or further improvements. The claims at the end hereof are intended as the chief aid toward this purpose, as it is these that meet the requirement of pointing out the parts, improvements, or combinations in which the inventive concepts are found.
The water in a water circuit, generally 1, is circulated by a pump 2 between a heat exchanger 5 and the radiators 3. The heated water flows from the heat exchanger through a feedline 6 and returns through a venturi 4. In the feedline 6 are a temperature-limiting control thermostat 7 and a feed thermostat 8.
Gas is supplied to burner 14 through a gas control indicated generally by reference number 16 through a supply socket 10 a . The gas control 16 is basically of L-shape, comprising a horizontally disposed branch 10 and a vertically disposed branch 9. The horizontal branch 10 contains a spring-loaded disc valve 11 which also is urged in the closing direction by gas pressure. Valve 11 is controlled by a water-actuating device 12 one of whose diaphragm chambers is biased by the negative pressure in the venturi nozzle 4. Diaphragm 12 actuates valve 11 through a push rod 11 a . The passage of the gas is also controlled by a gas valve 13 in the vertical branch 9 of the gas fitting 16 before it reaches the gas burner 14. The gas burner is electronically monitored by a flame-sensing means 17 and electrically ignited, features which are known and, in the interests of simplicity, the latter is not shown in the drawing. The gas valve 13 is operated by an electromagnet 15 through a push rod 13 a . The armature of the electromagnet is connected to a dashpot device so that the operation thereof is delayed.
An electrical circuit, generally 18, includes (starting from R/Mp) a branch through only switch 7' to the motor of pump 2 and a second branch through switch 7', switch 8' and switch 17' controlling electromagnet 15. Through switch 7', the temperature-limiting device 7 controls the circulating pump 2 and the electromagnet 15. The feed thermostat 8 and the flame-sensing means 17 only control the magnet 15 through switches 8' and 17' respectively.
During heating operation and when the temperature preselected on the feed thermostat 8 is reached (e.g. 185° F.), the switch 8' of the feed thermostat opens. This interrupts the circuit of the electromagnet 15 so that the gas valve 13 closes by reason of the spring pressure thereon. The gas path is thereby blocked and the heating is interrupted until the circulating heating water is cooled to the switching-on temperature. If there is a fault in this control procedure so that heating is continued despite the fact that the preselected feed temperature was reached, the circuit of the switch 7' of the temperature-limiting device 7 and controlling the circulating pump 2 and the electromagnet 15, is opened when a preselected limiting temperature (e.g. 205° F.) is reached. The pump 2 is stopped and this results in response of the diaphragm-actuating device 12 so that the gas valve 11 closes (low water safety valve) and also blocks the passage of gas to the gas burner. The flame-sensing means 17 opens switch 17' should the flame go out.
The invention relates to a forced circulation gas water heater for operating a hot water heating system and comprising: a gas fitting in the gas path to the burner, which fitting has an L-shaped gas passage with a gas valve in each branch of the gas passage, each of which valves are a plate valve and are operated by a push rod, the push rods of the two gas valves being disposed in cruciform pattern relative to each other; a diaphragm-actuating member adapted to respond to the flow pressure in the circulating water path operatively associated with the push rod of one of said gas valves; a magnet whose armature is operatively associated with the push rod of the other gas valve; and a temperature-limiting control which can be actuated by a thermostat which responds to excess temperature.
A requirement for forced circulation gas water heaters is to have a gas safety valve, controlled by a temperature-limiting device, in addition to the gas valve which is controlled by the room thermostat and feed thermostat as well as by the flame monitor.
In forced circulation water-heating systems with a thermoelectric ignition safety device, the temperature-limiting switch is connected in the thermostat circuit so that the limiting switch interrupts the thermostat circuit in the event of excess temperature thus causing the ignition safety valve to close. However, an ignition safety valve of the kind heretofore described is not provided in apparatus having electronic flame monitoring for the burner. Accordingly, such apparatus requires an electrically controllable gas safety valve which is governed by the temperature-limiting device.
It has already been proposed for the temperature-limiting device switch, taking the form of an electric switch which opens with rising temperature, to be connected in circuit of the circulating pump, which pump in turn governs a low water safety valve via a diaphragm-actuating member responding to the closing pressure in the water-circulating path.
The prior art also discloses a system in which a gas fitting with an L-shaped gas passage is provided in the gas path to the burner. One gas valve each, constructed as plate valve, is provided in each branch of the L-shaped gas passage. The gas valve in the horizontal branch is the ignition safety valve which may be pushed open by means of a horizontally disposed push rod actuated by a manually operated pushbutton. A gas valve, which can be operated by an electromagnet via a vertically disposed push rod, is positioned in the vertical branch of the gas passage. The room thermostat and feed thermostat, as well as a switch contact operated by a diaphragm-actuating element which responds to the flow pressure in the water circulation path is connected in the circuit of the electromagnet.
It is an object of the invention to provide a forced circulation gas water heater of the kind mentioned heretofore which is as simple as possible and to construct it from a minimum number of parts.
It is a further object of the invention to provide a forced circulation gas water heater in which the flame is monitored by an electronic flame monitor and in which a gas valve is provided which is controlled by the temperature-limiting device and is independent of the flame monitor.
According to the invention this is achieved in that the diaphragm-actuating element acts directly on the horizontally disposed valve push rod of the fitting and the temperature limiter is connected in the circuit of the water-circulating pump; the ionization apparatus (flame monitor) controls the circuit of the magnet controlling the actuation of the vertically disposed push rod of the gas valve operated by the magnet.
DESCRIPTION OF THE DRAWING
The drawing illustrates diagrammatically a system embodying the invention with the electrical, but not the gas, circuit in "operating" position.
DESCRIPTION OF SPECIFIC EMBODIMENT
The following disclosure is offered for public dissemination in return for the grant of a patent. Although it is detailed to ensure adequacy and aid understanding, this is not intended to prejudice that purpose of a patent which is to cover each new inventive concept therein no mater how others may later disguise it by variations in form or additions or further improvements. The claims at the end hereof are intended as the chief aid toward this purpose, as it is these that meet the requirement of pointing out the parts, improvements, or combinations in which the inventive concepts are found.
The water in a water circuit, generally 1, is circulated by a pump 2 between a heat exchanger 5 and the radiators 3. The heated water flows from the heat exchanger through a feedline 6 and returns through a venturi 4. In the feedline 6 are a temperature-limiting control thermostat 7 and a feed thermostat 8.
Gas is supplied to burner 14 through a gas control indicated generally by reference number 16 through a supply socket 10 a . The gas control 16 is basically of L-shape, comprising a horizontally disposed branch 10 and a vertically disposed branch 9. The horizontal branch 10 contains a spring-loaded disc valve 11 which also is urged in the closing direction by gas pressure. Valve 11 is controlled by a water-actuating device 12 one of whose diaphragm chambers is biased by the negative pressure in the venturi nozzle 4. Diaphragm 12 actuates valve 11 through a push rod 11 a . The passage of the gas is also controlled by a gas valve 13 in the vertical branch 9 of the gas fitting 16 before it reaches the gas burner 14. The gas burner is electronically monitored by a flame-sensing means 17 and electrically ignited, features which are known and, in the interests of simplicity, the latter is not shown in the drawing. The gas valve 13 is operated by an electromagnet 15 through a push rod 13 a . The armature of the electromagnet is connected to a dashpot device so that the operation thereof is delayed.
An electrical circuit, generally 18, includes (starting from R/Mp) a branch through only switch 7' to the motor of pump 2 and a second branch through switch 7', switch 8' and switch 17' controlling electromagnet 15. Through switch 7', the temperature-limiting device 7 controls the circulating pump 2 and the electromagnet 15. The feed thermostat 8 and the flame-sensing means 17 only control the magnet 15 through switches 8' and 17' respectively.
During heating operation and when the temperature preselected on the feed thermostat 8 is reached (e.g. 185° F.), the switch 8' of the feed thermostat opens. This interrupts the circuit of the electromagnet 15 so that the gas valve 13 closes by reason of the spring pressure thereon. The gas path is thereby blocked and the heating is interrupted until the circulating heating water is cooled to the switching-on temperature. If there is a fault in this control procedure so that heating is continued despite the fact that the preselected feed temperature was reached, the circuit of the switch 7' of the temperature-limiting device 7 and controlling the circulating pump 2 and the electromagnet 15, is opened when a preselected limiting temperature (e.g. 205° F.) is reached. The pump 2 is stopped and this results in response of the diaphragm-actuating device 12 so that the gas valve 11 closes (low water safety valve) and also blocks the passage of gas to the gas burner. The flame-sensing means 17 opens switch 17' should the flame go out.