DE2625736A1 - Central heating gas burner output adjusting system - has motorised valve for short circuiting diaphragm valve for heating medium - Google Patents

Abstract

Gas fired central heating burner feed channels are controlled by digital flow rate limiting device. The latter is actuated by a diaphragm valve loaded by the dynamic pressure by the heated medium flowing through a heat source. The path of the heating medium has changeover valve for short circuiting the diaphragm valve. The heat source output is automatically adjusted to the quantity of heat required at any required time. The electrical circuit of the switching motor (12) for the changeover valve has a contact (21) of an external sensor (23). The changeover valve (14) actuated by motor in the pipeline (11) has two positions. These positions ensure flow in two directions (15) and (16). In one direction (16) the pipeline (11) is connected by a short circuiting line (18) with the draining line (10) and this also ensures that the diaphragm valve (8) is ineffective.

Description

Fuel-heated heat source

The present invention is directed to fuel fired Heat source according to the preamble of the claim.

From the UT-PS 20 52 404 is a part-load controlled .därmequelle for a Umiaufwasserhizer with domestic water operation become known in the dependency from the circulating water stream, a diaphragm arranged in the gas path over a membrane switch is adjusted.

The arrangement is created in such a way that the gas throughput limiting element the heat source in domestic water operation the one position with the greater throughput, in the case of tleizungsbetrieb, however, the throttled, other indoor position.

In particular, with hot water operation, the problem arises that the Temperature of the circulating water heater in the domestic water heater on a certain Keeping the level is to provide the consumer with instant hot water of the desired level To be able to offer temperature. This means that even when the heating system is not in operation, So in summer, the heat source has to go into operation more often to keep the water volume, according to the volume of the heat source, the pipes and the domestic water heater keep on temperature. Here, however, no heat is used profitably, because this process takes place independently of the consumer's tap water requirement.

There are still central heating systems that are controlled depending on the outside temperature Flow temperature known, see DT-AS 19 28 575.

In heating and sanitary engineering, the term so-called annual efficiency has emerged, which reads: In this equation, rj = annual efficiency, Qk = heat source efficiency, riv = distribution efficiency (pipeline losses), b = annual operational time, b = annual operational time and qb = operational readiness loss.

From the position of the elements in the formula it can be seen that with constant heat source and distribution efficiency, the number for the annual efficiency Can be decisively improved if the ratio of operational readiness is kept as small as possible during operating time.

The present invention is accordingly based on the object of providing a automatic output adjustment of the heat source to the time required amount of heat to reach.

The solution to this problem takes place with the in the characterizing part of the claim specified measure.

This has the advantage of ensuring that the annual efficiency is increased and thus a significant energy saving is achieved. The invention lies here the knowledge is based on a large part of the operating conditions "operating time with To replace full load / operational time with an operating time with partial load, where the partial load is controlled depending on the outside temperature and so is the operating time at full load as well as to minimize the operational readiness time.

An embodiment of the invention is based on the enclosed Drawing explained in more detail, which the essential elements of the partial load control in Showing principle. A gas water heater, not shown, of course a valve-controlled burner, a heat exchanger, a flow and return line for the water to be heated and a consumer, has in the gas supply channel a choke 1 that can occupy two discrete positions. These locations are from a Actuator 2 controlled and are either the fully open position or the partially closed position. The actuator is hinged by a pin 3, which of a two-armed lever 4 is controlled, which can be pivoted about a pivot point 5. The lever in turn is actuated by a diaphragm pin 6, which is in dependence of the position of a membrane 7, which is pressure-tight inside a membrane switch 8 is clamped, moved. Two pressure chambers 9 and 10 of the membrane are with lines 11 and 12 in connection with pressure medium.

In the line 11 is a switchover valve controlled by an electric motor 13 14 switched on, which has two possible positions, namely the position in Direction of arrow 15 and that in the direction of arrow 16. In the latter The operating direction is the line 11 via a short-circuit line 18 to the drain line 19 connected, the membrane switch 8 so switched ineffective.

The membrane switch 8 is under the action of a return spring 20, which presses the membrane or the membrane pin into the position shown. That Reversing valve 14 is in the position shown by arrow 16.

The electric motor 13 is connected to a supply voltage R / Mp, in which Path a contact 21 is placed, which is open in the idle state. This contact will acted upon by a thermal motor 22, the function of which depends on a Outside temperature sensor 23 is through a building outer wall 24 is led through into the open. The outside temperature sensor works according to the principle the thermal expansion of a liquid.

The function of the partial load control just shown is as follows: Since the circuit for the voltage source R and Mp through the open contact 21 is interrupted, the electric motor 13 is de-energized. The reversing valve 14 is located in one end position, so that the pressure in lines 17 and 19 is unequal is.

The membrane switch 8 is thus acted upon by differential pressure, the return spring 20 is stretched, the throttle 1 is in the end position, which only a partial gas flow allowed to the burner, not shown, of the heat source.

Now the outside temperature falls below a set changeable one Value, the contact 21 closes. The electric motor 13, which is energized, controls the reversing valve 14 in the second position, so that the line 17 is closed. The pin 6 then adjusts the lever 4 under the action of the restoring force of the Spring 20, so that the gas throttle 1 is adjusted to its other working position, at which the maximum permissible gas flow is led to the burner.

Claim:

Claims (1)

Patent claim Fuel-heated heat sources with a fluid-fed one Burner to which the fuel is fed via a feed channel in which a digital Throughput limiting member is arranged, which is operated by a tienibranschalter is the one to be heated by the flow pressure of the medium passing through the heat source is acted upon, whereby in the path of the medium one of an electric switching motor driven changeover valve is provided for short-circuiting the membrane switch, characterized in that a contact (21) in the circuit of the switching motor (12) an outside temperature sensor (23) is arranged.