Heating system

[GARYF]

Hi,

I am replacing an indirect cylinder and have a few queries:

1) The boiler is a Baxi. It has a gas feed at the bottom and a flow and return at the top. The pump is fitted in the flow on the top of the boiler. In the loft is a DHW header tank and a feed and expansion tank feeding a indirect copper cylinder. There is no thermostat on the cylinder, how does the boiler know when the water is to temp? There is also an immersion fitted.

2) There are no TRV'S or room thermostats! How does the boiler know when to shut off? There is a dial on boiler for temp, is this the only method of control?

3) Cant seem to find a 3 way valve, is it possible that there isnt one?

Thanks in advance for any advice given,

Gary.

[jondeau]

The boiler thermostat is the only method of controlling the hot water with this sort of system.

It used to be quite common to instal systems in this manner.......3 way valves were the exception some years ago.

It is probable that somewhere in the house (very often the hall) there is ,or was, a thermostat to control the radiators.