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

On Thu, 22 Sep 2005 12:25:09 +0100, MattH wrote:

I have recently moved into a larger house and am having soem
problems with the radiators not getting hot,
snip
The house has 23 radiators of which 18 are large doubles,

Does the boiler have sufficient output for that number and size of
rads?

--
Cheers
Dave. pam is missing e-mail

Dave Liquorice wrote:
MattH wrote:
The house has 23 radiators of which 18 are large doubles,

Kinell.

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.
--
Cheers,
Set Square
______
Please reply to newsgroup. Reply address is invalid.

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

In article ,
says...

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,

Do the servants have central heating too, or do they just have to work
hard to keep warm?

I wouldn't say 23 rads is that excessive - I live in a modest 3-bed
detached and that has 13!

It could be that the radiators are sludged up at the inlet - in a
previous house, I had large double rads that didn't heat up until the
heating had been on for hours - they were almost cold to touch at the
inlet, but the pipe was very hot. They were sludged up quite badly -
after remvoving them and hosing them out we found they heated up to a
good temp.

"MattH" wrote in message
...

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.

Lots of elbows can defeat it. Otherwise put another pump in series (two
together). This will get the pressure up. I have seen a pump on the flow
and one on the return and that worked quite well. The boiler can act as a
big restrictor to flow. One pumping into the boiler and one pumping out.

It will be better if you split the system up into two zones. Say, upstairs
and downstairs, and have a pump and non-return valve on each. Grundfos do
twin pumps sets for this. Then you divide the system up. You can also have
each zone on separate temperature stats and timers. Upstairs can be off
during the day and only on during bedtime and in the mornings. This is the
best approach as it solves the problem and saves on fuel bills.

In an earlier contribution to this discussion,
Doctor Drivel wrote:


It will be better if you split the system up into two zones. Say,
upstairs and downstairs, and have a pump and non-return valve on
each. Grundfos do twin pumps sets for this. Then you divide the
system up. You can also have each zone on separate temperature stats
and timers. Upstairs can be off during the day and only on during
bedtime and in the mornings. This is the best approach as it solves
the problem and saves on fuel bills.

Perhaps I should emphasise that having twin pumps isn't a pre-requisite for
zoning. It is perfectly feasible - indeed more common than not - to have a
single pump for multiple zones. After all, you're only going to have one
boiler - or *are* you?!!!
--
Cheers,
Set Square
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"Set Square" wrote in message
...
In an earlier contribution to this discussion,
Doctor Drivel wrote:


It will be better if you split the system up into two zones. Say,
upstairs and downstairs, and have a pump and non-return valve on
each. Grundfos do twin pumps sets for this. Then you divide the
system up. You can also have each zone on separate temperature stats
and timers. Upstairs can be off during the day and only on during
bedtime and in the mornings. This is the best approach as it solves
the problem and saves on fuel bills.

Perhaps I should emphasise that having twin pumps isn't a pre-requisite
for
zoning. It is perfectly feasible - indeed more common than not - to have a
single pump for multiple zones. After all, you're only going to have one
boiler - or *are* you?!!!

You must learn to focus. The problem appears that the pump is not man
enough. Using two to great effect and also give zoning, which saves energy
and lowers bills is the way. Got it?

Or two system boilers with their own integrated pumps for each zone also, if
the boiler also is not man enough. Got it?

In an earlier contribution to this discussion,
Doctor Drivel wrote:


You must learn to focus. The problem appears that the pump is not man
enough. Using two to great effect and also give zoning, which saves
energy and lowers bills is the way. Got it?

On the contrary, *you* must learn to focus.

Suprisingly(!) I was not saying that yours was not a valid solution - but
simply that it wasn't the *only* valid solution.

Let's not lose sight of the fact that these posts are read by many people -
not just by those who ask the questions - and I wouldn't want anyone to jump
to the conclusion that you *have* to have multiple pumps in order to achieve
zoning. Your previous post could have been interpreted thus.
--
Cheers,
Set Square
______
Please reply to newsgroup. Reply address is invalid.

"Set Square" wrote in message
...
In an earlier contribution to this discussion,
Doctor Drivel wrote:


You must learn to focus. The problem appears that the pump is not man
enough. Using two to great effect and also give zoning, which saves
energy and lowers bills is the way. Got it?

On the contrary, *you* must learn to focus.

Suprisingly(!) I was not saying that yours was not a valid solution - but
simply that it wasn't the *only* valid solution.

You must learn to focus. His pump appears too small for the system. The
next size up is very "expensive", so doubling up is in order. Adding
another pump can also zone off. Got it?

Let's not lose sight of the fact that these
posts are read by many people -

Exactly and I hope they don't take much notice of you.

On Thu, 22 Sep 2005 12:25:09 +0100, 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.

If the rads are not getting hot - then the question is what is the boiler
doing.

A) Flat out alway s running - i.e. it's not powerfull enough for the 23
rads.
OR
B) The boiler is getting very hot but there is not distribution of the
heat to the rads this can be any number of problems. And 'pump needs
to be bigger' is at the end of the list.

--
Ed Sirett - Property maintainer and registered gas fitter.
The FAQ for uk.diy is at http://www.diyfaq.org.uk
Gas fitting FAQ http://www.makewrite.demon.co.uk/GasFitting.html
Sealed CH FAQ http://www.makewrite.demon.co.uk/SealedCH.html