Head scratching time. I have ana Ideal Classic boiler system that has
a header tank and the radiators will only work so long as the water is
being heated and the bathroom rad is always on - I don't know the
technical name for that kind of system.

Anyway, I had a leaky thermostatic rad valve that needed replacing so
drained the system, replaced leaky valve and filled the system again,
bled the radiators switched the room thermostat in the hall up
full,put the boiler on a higher setting (number 5 instead of the usual
3, and switched the boiler on using the timer.

The water is heating and the bathroom radiator is hot but ...... the
boiler doesn't stay on for long and the rads do not warm up - none of
them, including those without thermostatic vavles. I can't easily
access the pump becaus ethat means ripping up the bathroom floor! so
not too keen on that idea! I think I can hear its motor werring when I
switched the boiler on.

I left it for half an hour but nothing only the water heats - any
ideas welcome

Paul-the-Pen wrote:
Head scratching time. I have ana Ideal Classic boiler system that has
a header tank and the radiators will only work so long as the water is
being heated and the bathroom rad is always on - I don't know the
technical name for that kind of system.

Anyway, I had a leaky thermostatic rad valve that needed replacing so
drained the system, replaced leaky valve and filled the system again,
bled the radiators switched the room thermostat in the hall up
full,put the boiler on a higher setting (number 5 instead of the usual
3, and switched the boiler on using the timer.

The water is heating and the bathroom radiator is hot but ...... the
boiler doesn't stay on for long and the rads do not warm up - none of
them, including those without thermostatic vavles. I can't easily
access the pump becaus ethat means ripping up the bathroom floor! so
not too keen on that idea! I think I can hear its motor werring when I
switched the boiler on.

I left it for half an hour but nothing only the water heats - any
ideas welcome

Is it a system where the hot water is heated by a non-pumped loop and
the pump turns on to push the water round the radiators?

Could possibly be that muck in the system gathered in one place and is
causing grief. Far, far more likely that you have an air lock somewhere
in the system. I have a nightmare getting the air out of my system every
time I drain it down.
Any valves other than on the radiators you can try opening?
Any joints in higher areas you could carefully loosen off a bit?
A few towels on hand is advisable!!

Be careful running the pump too long. It may be full of air and not have
any lubricating water in it.

On 17 Oct, 19:21, Invisible Man wrote:
Paul-the-Pen wrote:
Head scratching time. I have ana Ideal Classic boiler system that has
a header tank and the radiators will only work so long as the water is
being heated and the bathroom rad is always on - I don't know the
technical name for that kind of system.

Anyway, I had a leaky thermostatic rad valve that needed replacing so
drained the system, replaced leaky valve and filled the system again,
bled the radiators switched the room thermostat in the hall up
full,put the boiler on a higher setting (number 5 instead of the usual
3, and switched the boiler on using the timer.

The water is heating and the bathroom radiator is hot but ...... the
boiler doesn't stay on for long and the rads do not warm up - none of
them, including those without thermostatic vavles. I can't easily
access the pump becaus ethat means ripping up the bathroom floor! so
not too keen on that idea! I think I can hear its motor werring when I
switched the boiler on.

I left it for half an hour but nothing only the water heats - any
ideas welcome

Is it a system where the hot water is heated by a non-pumped loop and
the pump turns on to push the water round the radiators?

Could possibly be that muck in the system gathered in one place and is
causing grief. Far, far more likely that you have an air lock somewhere
in the system. I have a nightmare getting the air out of my system every
time I drain it down.
Any valves other than on the radiators you can try opening?
Any joints in higher areas you could carefully loosen off a bit?
A few towels on hand is advisable!!

Be careful running the pump too long. It may be full of air and not have
any lubricating water in it.- Hide quoted text -

- Show quoted text -

I think the pump only works the rad heating not the water heating. I
used a system cleaner before draining and surprised how clean the
water was coming out. I flushed the system a few times before fitting
the new TRV. I am beginning to think that perhaps there is an airlock
in the pump as it seems likely to me that if air is stuck in there the
motor would make a noise but not circulate the water

Does that sound logical?

On Sat, 17 Oct 2009 11:04:37 -0700, Paul-the-Pen wrote:

Head scratching time. I have ana Ideal Classic boiler system that has
a header tank and the radiators will only work so long as the water is
being heated and the bathroom rad is always on - I don't know the
technical name for that kind of system.

Anyway, I had a leaky thermostatic rad valve that needed replacing so
drained the system, replaced leaky valve and filled the system again,
bled the radiators switched the room thermostat in the hall up
full,put the boiler on a higher setting (number 5 instead of the usual
3, and switched the boiler on using the timer.

The water is heating and the bathroom radiator is hot but ...... the
boiler doesn't stay on for long and the rads do not warm up - none of
them, including those without thermostatic vavles. I can't easily
access the pump becaus ethat means ripping up the bathroom floor! so
not too keen on that idea! I think I can hear its motor werring when I
switched the boiler on.


Sounds like air in part of the system preventing proper circulation. First
off I'd look for air-bleed valves around the pipework in the airing
cupboard or any high points on pipe runs. If there's nothing you can bleed
it could be an air-lock in a pipework run, which can be a right pain to
clear: I've resorted to connecting mains to the vent pipe so water gets
forced back up the feed into the F&E tank and out via the overflow. This
can also clear blockages where muck has gone down the flow pipe as the
header tank emptied.



--
John Stumbles -- http://yaph.co.uk

Never believe anyone who claims to be a liar

In an earlier contribution to this discussion,
YAPH wrote:

On Sat, 17 Oct 2009 11:04:37 -0700, Paul-the-Pen wrote:

Head scratching time. I have ana Ideal Classic boiler system that has
a header tank and the radiators will only work so long as the water
is being heated and the bathroom rad is always on - I don't know the
technical name for that kind of system.

Anyway, I had a leaky thermostatic rad valve that needed replacing so
drained the system, replaced leaky valve and filled the system again,
bled the radiators switched the room thermostat in the hall up
full,put the boiler on a higher setting (number 5 instead of the
usual 3, and switched the boiler on using the timer.

The water is heating and the bathroom radiator is hot but ...... the
boiler doesn't stay on for long and the rads do not warm up - none of
them, including those without thermostatic vavles. I can't easily
access the pump becaus ethat means ripping up the bathroom floor! so
not too keen on that idea! I think I can hear its motor werring when
I switched the boiler on.


Sounds like air in part of the system preventing proper circulation.
First off I'd look for air-bleed valves around the pipework in the
airing cupboard or any high points on pipe runs. If there's nothing
you can bleed it could be an air-lock in a pipework run, which can be
a right pain to clear: I've resorted to connecting mains to the vent
pipe so water gets forced back up the feed into the F&E tank and out
via the overflow. This can also clear blockages where muck has gone
down the flow pipe as the header tank emptied.


Yes, it certainly sounds like an air-lock. One thing to try is to give each
radiator a really good bleed - one side at a time. That is, bleed with one
valve closed and the other one open - then swap round. That way, you ensure
that both the flow and return pipes are full of water. You'll need to bleed
out a litre of water or more with each valve open to ensure that the pipes
are full.
--
Cheers,
Roger
______
Email address maintained for newsgroup use only, and not regularly
monitored.. Messages sent to it may not be read for several weeks.
PLEASE REPLY TO NEWSGROUP!

Having taken everyone's advice I managed to fix the problem employing
a variety of suggestions and, should anyone have the same problem,
he's the low down:

Bled a pint of water out of every radiator having discovered there
were no bleed valves on any upper floor pipes. That didn't work at
first but one upstairs radiator suddenly started to gurgle, so I bled
it while the heating was one - hey presto it got hot - ouch! did it
get hot I could hardly hold the key!

But that was the only rad that heated up, this seemed to confirm it
was an airlock. I had another look at all the other rads - nothing
happened so I went outside and attached a hose to each of the two
drain cocks in turn forcing mains water in to them.

Bingo! all rads getting warm but only at the top of them! this I
assumed meant air still in the system blocking the run of water so
bled out another pint or so of water from each rad as they slowly got
warmer and warmer evenly.

I now have a system tha is a lot quiter than it's ever been and a lot
warmer I've had to turn that boiler thermostat down from it's usually
three and a half to two! - so well pleased about that!