GB1589849A

GB1589849A - Wall mountable electrically heatable water boiler for central heating and domestic water heating systems

Info

Publication number: GB1589849A
Application number: GB5035677A
Authority: GB
Original assignee: Individual
Current assignee: Individual
Priority date: 1977-03-21
Filing date: 1977-12-02
Publication date: 1981-05-20
Also published as: NL7713249A; DE7736213U1; YU287777A; FR2385047A1; LU78575A1; DK525577A; BE861291A

Description

(54) IMPROVEMENTS IN OR RELATING TO A WALL MOUNTABLE, ELECTRICALLY HEATABLE, WATER BOILER FOR CENTRAL HEATING AND DOMESTIC WATER HEATING SYSTEMS (71) I, ZIVOJIN STAJIC, a Yugoslav citizen, of 4bis, avenue Sambre-et-Meuse, 93220 Gagny, Seine Saint-Denis, France, do hereby declare the invention, for which I pray that a patent may be granted to me, and the method by which it is to be performed, to be particularly described in and by the following statement:- This invention relates to a wall mountable, electrically eatable, water boiler for central heating and domestic water heating systems.

Electrically heated boilers are already known for heating water for radiators of a central heating system and at the same time for heating water for a domestic hot water supply system, but these boilers are very clumsy and unsuitable for installation in small premises and fiats.

For such small premises, it has been customary to install gas water boilers but these have many disadvantages, particularly the fact that a pilot gas jet is permanently lit and in some cases this can cause serious accidents either of explosion or causing fire.

There is thus a need for an improved electric water boiler able to heat water for a central heating system and simultaneously water for a domestic hot water system.

According to the invention, there is provided a wall mountable, electrically heatable, water boiler for central heating and domestic water heating systems, including a housing for containing water for the central heating system, which housing is directly connected to an expansion chamber and contains electrical resistance heating elements whose electrical supply is controlled by an automatic device which, depending on the temperature of the central heating system water in the housing, turns on and off the electrical supply to the heating elements, a pipe for containing water to be heated for the domestic hot water system, which pipe is in the form of a series of coils contained in the housing with each heating element being mounted substantially in the centre of a respective coil of the series, a by-pass water circuit connectible to a cold water source for passing incoming cold water to the housing and central heating system by-passing the domestic water system, and a pump for circulating through the pipe water being, or to be, heated by the heating elements.

For a better understanding of the present invention, and to show how the same may be carried into effect, reference will now be made, by way of example, to the accompanying drawing, in which: Figure 1 is a diagrammatic partially sectioned view of a wall mountable, electri calls heatable, water boiler according to the invention, Figure 2 is a cross sectional view taken substantially along line 11-11 of Figure 1, and Figure 3 is a circuit diagram for the connection of heating elements of the boiler of Figures 1 and 2.

In Figure 1, a wall mountable, electrically heatable water boiler according to the invention has a closed housing 1, of a substantially right-angled parallelepipedic shape for containing water to be heated for a central heating system and having at its top 2, an automatic air-vent 3 for bleeding air from the central heating system.

The housing 1, which has a volume in proportion to the required central heating output, is small enough to be easily mounted on a wall, for example that of a kitchen, a bath-room, or other small room.

Generally the housing 1 is made of metal resistant to corrosion and is preferably made of stainless steel. This housing is connected at its lower portion 4 by a duct 5 to an expansion chamber 6 placed behind the housing 1. The bottom 4 of the housing 1 supports a plurality of, in this case three, reinforced resistance heating elements 7, 8, 9 each of which is surrounded by a respective coil 10, 11, 12 of a series of coils in a pipe for containing water to be heated for a domestic hot water supply system. The end 10a of the coil 10 is connectible as an inlet to a cold water supply and end 12a of the coil 12 is connectible as an outlet to a distribution conduit for hot water for a kitchen, a bathroom, or the like.

A connection 13 to the cold water supply includes a bypass conduit 14 which, through a first valve 15 then a second valve 16, is connected to a water inlet 17 in the lower portion of the housing 1. An upper water outlet 18 in the housing, collecting hot water produced by the boiler for the central heating system runs, through a pipe 19, to a pump 20 then to a three-way valve 21. The valve 21 is connected to a water inlet 22 of the housing 1 for the central heating water and to a pipe 23 connecting the housing 1 to heat exchanger radiators in the central heating system.

Numeral 24 designates a return duct from the central heating system to the water inlet 17 of the housing 1. A pressure gauge 25 is provided on by-pass conduit 14 between the valves 15 and 16 in order to check the prcssure of the circulating central heating water.

The heating elements 7, 8 and 9 are connected in series to a feed line 26 and to a gencral switch 27 controlled by a relay 28 with the current supply to the relay being itself controlled by an automatic device 29, commonly called "Aquastat", (Registered Trade Mark) similar to a thermostat turning on and off the switch 27 through the relay 28 depending on the temperature of the water contained in the housing 1.

In the winter season, the water heated in the housing 1 runs out at 18 at an elevated temperature and is then put in circulation through the central heating system under a low pressure by the pump 20, via the valve 21 and the duct 23. The central heating water returns at a lower temperature via the duct 24 and the inlet 17 to the lower portion of the housing 1 in which it is heated again.

In the summer season, the three-way valve 21 is activated and the hot water contained in the housing 1 comes out from the outlet 18, passes through the pump 20, and then, through the valve 21, returns by the duct 22 back into the housing 1 in order to ensure a closed circuit.

In some cases and in order to prevent a significant loss of heat, the housing 1 as well as some of the ducts 19, 23, 24 are heat insulated. However, if the boiler 1 is used to heat the premises in which it is installed, it has not necessarily be to heat insulated.

Various modifications may moreover be made to the embodiment of the invention given as an example, without departing from the scope of the invention, as defined in the appended claims. More particularly, the three way valve 21 can be omitted. In such a case, an atmosphere thermostat is mounted in the premises to be centrally heated and controls the current supply of the pump 20 in such a way to cut off its current supply when the temperature of the premises is sufficicnt so that water circulation in the heating system is stopped.

WHAT I CLAIM IS: 1. Wall mountable, electrically heatable, water boiler for central heating and domestic water heating systems, including a housing, for containing water for the central heating system, which housing is directly connected to an expansion chamber and contains electrical resistance heating elements whose electrical supply is controlled by an automatic device which, depending on the temperature of the central heating system water in the housing turns on and off the electrical supply to the heating elements, a pipe for containing water to be heated for the domestic hot water system, which pipe is in the form of a series of coils contained in the housing with each heating element being mounted substantially in the centre of a respective coil of the series, a by-pass water circuit connectible to a cold water source for passing incoming cold water to the housing and central heating system by-passing the domestic water system, and a pump for circulating through the pipe water being, or to be, heated by the heating elements.

2. Boiler according to claim 1, including a three way valve connectible between a central heating water inlet and a central heating water outlet of the housing and operable to by-pass a central heating system.

3. Boiler according to claim 1 or claim 2, wherein the heating elements are reinforced electrical resistor heating elements connectible to a source of electrical supply via a switch controlled by the automatic device.

4. A wall mountable, electrically heatable, water boiler, substantially as hereinbefore described with reference to the accompanying drawings.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. is connectible as an outlet to a distribution conduit for hot water for a kitchen, a bathroom, or the like. A connection 13 to the cold water supply includes a bypass conduit 14 which, through a first valve 15 then a second valve 16, is connected to a water inlet 17 in the lower portion of the housing 1. An upper water outlet 18 in the housing, collecting hot water produced by the boiler for the central heating system runs, through a pipe 19, to a pump 20 then to a three-way valve 21. The valve 21 is connected to a water inlet 22 of the housing 1 for the central heating water and to a pipe 23 connecting the housing 1 to heat exchanger radiators in the central heating system. Numeral 24 designates a return duct from the central heating system to the water inlet 17 of the housing 1. A pressure gauge 25 is provided on by-pass conduit 14 between the valves 15 and 16 in order to check the prcssure of the circulating central heating water. The heating elements 7, 8 and 9 are connected in series to a feed line 26 and to a gencral switch 27 controlled by a relay 28 with the current supply to the relay being itself controlled by an automatic device 29, commonly called "Aquastat", (Registered Trade Mark) similar to a thermostat turning on and off the switch 27 through the relay 28 depending on the temperature of the water contained in the housing 1. In the winter season, the water heated in the housing 1 runs out at 18 at an elevated temperature and is then put in circulation through the central heating system under a low pressure by the pump 20, via the valve 21 and the duct 23. The central heating water returns at a lower temperature via the duct 24 and the inlet 17 to the lower portion of the housing 1 in which it is heated again. In the summer season, the three-way valve 21 is activated and the hot water contained in the housing 1 comes out from the outlet 18, passes through the pump 20, and then, through the valve 21, returns by the duct 22 back into the housing 1 in order to ensure a closed circuit. In some cases and in order to prevent a significant loss of heat, the housing 1 as well as some of the ducts 19, 23, 24 are heat insulated. However, if the boiler 1 is used to heat the premises in which it is installed, it has not necessarily be to heat insulated. Various modifications may moreover be made to the embodiment of the invention given as an example, without departing from the scope of the invention, as defined in the appended claims. More particularly, the three way valve 21 can be omitted. In such a case, an atmosphere thermostat is mounted in the premises to be centrally heated and controls the current supply of the pump 20 in such a way to cut off its current supply when the temperature of the premises is sufficicnt so that water circulation in the heating system is stopped. WHAT I CLAIM IS:

1. Wall mountable, electrically heatable, water boiler for central heating and domestic water heating systems, including a housing, for containing water for the central heating system, which housing is directly connected to an expansion chamber and contains electrical resistance heating elements whose electrical supply is controlled by an automatic device which, depending on the temperature of the central heating system water in the housing turns on and off the electrical supply to the heating elements, a pipe for containing water to be heated for the domestic hot water system, which pipe is in the form of a series of coils contained in the housing with each heating element being mounted substantially in the centre of a respective coil of the series, a by-pass water circuit connectible to a cold water source for passing incoming cold water to the housing and central heating system by-passing the domestic water system, and a pump for circulating through the pipe water being, or to be, heated by the heating elements.