John Rumm wrote:

It could be the cylinder thermostat cutting out too soon (if there is
one!)

Need to know more about the arrangement of valves etc, or if the
water is heated just by a gravity circulation loop.


Afraid that I haven't a clue how it's all plumbed in - it's a gas-fired
boiler on the ground floor. I do know that you can't just turn the
heating on, you need to turn the hot water on first and then turn on
the heating. Not sure if that's a clue or not?

What would determine how it's plumbed in? I think (from memory) that
there's a red wheel valve on one of the large pipes to (or maybe from)
the boiler, but I'm not 100% certain.

Thanks for your help.

I'm rather concerned that there's a leak somewhere to be honest, but
I'm hoping it's something far less serious and easier (and cheaper!) to
repair.
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