On Wed, 09 Mar 2005 13:47:28 +0000, David W.E. Roberts wrote:


"Old Bill" wrote in message
...
David W.E. Roberts wrote:
snip
However I was watching the flame and it was off most of the time.
This is the bit I don't understand.
If there is cold water running through the boiler, surely the flame
should
be on all the time?

Could some kind person suggest what the flock is going on?

Cheers
Dave R




Most combis devote all their power output to the hot water when its
demanded. I think we would need to know your make/model of boiler to
comment futher.

Unfortunately I didn't take down the details.
Following this up now for interest and because we vaguely know the owners.

I can understand 50% of the symptoms if the boiler switches to hot water
only when there is a demand.
This would explain the radiators cooling down.

What I still don't understand is why the boiler doesn't run continuously
when cold water is flowing through.
If the boiler was just underpowered then it should run all the time and
deliver warm water, not turn off and deliver cold water.

Also don't understand why it works for a while if the central heating is up
to temperature.

I suspect some kind of mis-connection or fault in the monitoring system
somewhere.

Without further investigations it's hard to pin down the precise reason
for poor HW.

However scaling of the secondary heat exchanger on the secondary side is
centre stage.

Also are poor water pressure/flow, poor gas supply, faulty boiler...



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Ed Sirett - Property maintainer and registered gas fitter.
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