On Fri, 10 Sep 2004 09:45:58 +0100, "Christian McArdle"
wrote:

Surely the boiler senses the return water temp and turn itself off
when only the bypass is open? That's how our system works where all
rads have TRVs (including in the room with the thermostat) and the
bypass is a length of pipe in the airing cupboard with a gate valve.
It works fine and the boiler shuts down when all the TRVs close. Or is
that what you mean by a boiler interlock - just a temp sensor in the
boiler? Are they not standard?

The problem is that without a room thermostat or flow switch, the boiler
won't know when any TRVs are opened. What will actually happen is that the
boiler will start burning again once the circuit has cooled down a little.
Your system, if left on at the height of summer, would actually use gas.
This is not acceptable under the law.

Christian.


It can be done with an outside temperature sensor as well.....


..andy

To email, substitute .nospam with .gl