US2468268A - Heating system - Google Patents

Description

' April 26, 1949. H. E. MORTON HEATING SYSTEM Filed June 13, 1947 A v M 7 M v w a [r y j 7 9 1 #7 v m m IN VEN TOR.

WK) E Morrow BY QMJ E724,

Patented Apr. 26, 1949 UNITED STATES; PATENT OFFICE HEATING SYSTEM Harry E. Morton, Hyde Park, Mass. Application June 13, 1947, Serial No. 754,493

2 Claims. 1

This invention relates to steam heating systems, and has an object to maintain heat in the radiators of such systems during the periods of the thermostats in the heated spaces are not calling for heat.

In an intermittently fired, one-pipe, steam heating system, such, for example, as one fired by an oil burner, the radiators usually get cold before the burner, started by an indoor thermostat, can heat the boiler sufliciently to again supply steam to the radiators. This results in the radiators being alternately hot and cold, and in discomfort during the ofi periods of the burner when the outdoor temperatures are relatively low.

This invention provides controls for an intermittently fired steam heating system, which results in steam being supplied to the radiators of the system during the off periods of the burner at low outdoor temperatures, thereby providing comfort equal to that provided by a conventional, hot water heating system.

The invention will now be described with reference to the drawing which illustrates diagrammatically, a one-pipe, steam heating system embodying this invention.

The conventional boiler 5 fired by a conventional oil burner 6 driven by an electric motor I, supplies steam through the pipe 8 to a radiator 9 having a conventional vent valve 20.

The motor I is connected to be started and stopped by the conventional control in which responds to the temperature of the boiler water, and by the conventional control thermostat II which responds to the temperature of the space heated by the radiator 9.

The steam pipe 8 contains the valve I! which acts as a vacuum breaker and which has the air bleed port lB therein. The port I8 is opened and closed by the piston I!) which responds to negative pressures in the boiler, and the opening or down movement of which is opposed by a spring 20. The port H in the valve I2 communicates with a closed chamber which, itself communicates with the atmosphere through the port l3. The piston 14 closes the port l3 and is movable by the hydraulic bellows IS. The bellows I5 is connected by the tube Hi to a conventional thermostat H which is exposed to the temperature of the outdoor air.

' It is obvious that when the port I3 is not closed by the piston I4, the port I8 will be opened to the atmosphere by the down movement of the piston l9. When the port I3 is closed by the atmosphere even though the piston is moves downward.

At one specific setting the thermostat I! may be adjusted to cause the bellows l5 to move the piston l4 toopen the port l3 at outdoor air temperatures above 34 F. and to close the port H at outdoor temperatures below 34 F'.

The piston I9 and the spring 20 may be ad: justed to open the port I8 when the negative pressure in the boiler reaches 10" of mercury.

The control I 0 which may be a conventional "Aquastat may be adjusted to maintain the boiler water at a mean temperature of about 175 F.,

The indoor thermostat ll may be adjusted to attempt to maintain a desired indoor temperature of F.

In operation the thermostat Il may call for heat and start the burner 6 to create steam in the boiler 5 and expel all air from the system through the valve 20. When the temperature surrounding the indoor thermostat l 1 reaches 75, the burner 6 will be stopped. Steam will con dense throughout the system, creating a negative pressure in all parts above the water level in the boiler. When this negative pressure reaches 10" of mercury the piston l9 will move downwardly to open the port Hi. If the outdoor temperature is above 34 F., the port i3 will be open, and consequently, the entire system will be vented to the atmosphere through the ports l8 and IS. The port l8 will remain open until the pressure Within the system stabilizes at 10 of mercury, negative pressure. As the negative pressure increases, the boiling point of the water in the boiler 5 drops so that vapor is continuously formed and the heat of evaporation can be obtained from the heat stored in the system. The boiling point at 10" of mercury is 193 F.

If the temperature surrounding the outdoor thermostat i1 is below 34 F., the port l3 will be closed by the piston I4, and although the port l8 may be opened as the negative pressure increases in the boiler, there can be no venting and no air will be bled into the boiler. The negative pressure in the boiler will continue to increase beyond 10" of mercury until the pressure equals 16.4 of mercury which corresponds to the temperature. At this point the Aquastat It) will start the motor I and the burner 6, thus adding heat to the water and causing more steam to flow to the radiator 9. The continued operation of the burner will raise the temperature of the water to the cut-off temperatureof the control l0 which piston H, the port i8 will not be opened to the I will again stop the motor.

' escapee It should be clear that valve [2 as described, will permit the heating system to operate as a vacuum system with a negative pressure which does not increase above of mercury whenever the outdoor temperature is greater than 34 F., thus producing the desirable hold-over characteristic necessary for this moderate temperature when the burner is stopped. The valve I: will also cause the system to act as a vacuum system when the outdoor temperature is less than 34 F. and maintain steam in the system during the periods when the burner is not operating.

It should be further understood that the above selected outdoor temperatures and water temperatures may be varied to suit the climatic conditions as they exist.

While one embodiment of the invention has been described for the purpose of illustration, it should be understood that the invention is not limited to the exact apparatus and arrangement of apparatus illustrated, as modifications thereof may be suggested by those skilled in the art without deparature from the essence of the invention.

What is claimed is:

1. A steam heating system comprising a boiler, a heat producer for heating the boiler, a radiator in the space to, be heated and connected to the boiler, a thermostat responsive to the temperature of said space for energizing said heat producer, means responsive to the temperature oi the boiler water for energizing said heat producer for maintaining the water at a predetermined minimum temperature, an air bleeding valve connected to the boiler, an outdoor thermostat, and means including said outdoor thermostat and including means responsive to pressure changes in theboiler for maintaining a predetermined negative pressure in the boiler and for actuating said l the boiler water for energizing said heat producer for maintaining the water at a predetermined minimum temperature, an air bleeding valve connected to the boiler, a port in said valve for bleeding air into the interior thereof, means including an outdoor air thermostat for opening and closing said port for bleeding air into said valve at outdoor temperatures above a predetermined temperature, a second port in said valve connecting the interior thereof with the interior of the boiler, and means responsive to changes in the pressure above the water level in the boiler tor opening and closing said second port for maintaining a predetermined negative pressure in said boiler.

HARRY E. MORTON.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED S TATES PATENTS Number Name Date 616,575 Jamer Dec. 27, 1898 1,921,708 Snavely Aug. 8, 1933 2,249,706 Ferguson July 15, 1941

Images