On Thu, 22 Sep 2005 19:53:38 +0100, "Set Square"
wrote:

In an earlier contribution to this discussion,
MattH wrote:

I have recently moved into a larger house and am having soem problems
with the radiators not getting hot, i have tried balancing which has
helped but really my question is, is the pump i have strong enough.
The house has 23 radiators of which 18 are large doubles, the pump is
a grundfos 15/60, which i understand is a powerful domestic model,
but i cant help thinking isnt up to the job.

Can anyone advise whether i can install a more powerful version, if so
what, or how can i check that this is strong enough, i cant help
feeling it isnt.

Thanks

You are probably asking the wrong question. Pumps don't generate heat -
well, not very much anyway - they simply distribute the heat generated by
the boiler.

So the first question needs to be whether the boiler is big enough.

When the system is on, is the boiler running continuously? Are there any
room thermostats? If so, what temperature are they set at?

If the boiler is running flat out this time of year, you haven't got a
prayer in the winter!

If the boiler is cycling on an off but the rads aren't very hot, it *could*
be the pump - or it could be the control system turning the boiler off when
it thinks the house is hot enough.

Is the *house* cold - or just the rads? If the latter, the system *may* be
doing its job properly.


What is the boiler thermostat set to ? Is it turned up near max.
Do any of the radiators get hot ?
If you turn half them off , do the other sget half ?

Robert

royall at which net