I've just had a plumber fit 2 new bigger radiators to replace 2 old
ones. The system was drained then refilled- all the other rads are OK
but the 2 new ones won't heat up at all.
We tried everything we could think of.
Bled the air out - they are full of water.
Turned all the other rads off and ran the pump.
Put a hose on the drain cocks that are fitted to both rads and ran
the water through till it was hot. Closed the drain cocks but no
hot water into the rads.
The property is a bungalow with solid floors and the pipework runs in
the loft and down the walls to the rads. These 2 rads are served by the
one pair of pipes until they reach skirting board level where they are
teed off to one rad in the lounge and the other through the wall to the
hall.
The tank is an old style primatic, central heating and domestic hot
water in the same tank, separated by an air pocket - but it seems to
work ok for all the other rads.
The valves are all new (one of them is thermostatic) - it seems a bit
unlikely that 2 of them would be blocked. The system has recently been
drained and flushed before they were fitted.
Any suggestions please?

In an earlier contribution to this discussion,
rob wrote:

I've just had a plumber fit 2 new bigger radiators to replace 2 old
ones. The system was drained then refilled- all the other rads are OK
but the 2 new ones won't heat up at all.
We tried everything we could think of.
Bled the air out - they are full of water.
Turned all the other rads off and ran the pump.
Put a hose on the drain cocks that are fitted to both rads and ran
the water through till it was hot. Closed the drain cocks but no
hot water into the rads.
The property is a bungalow with solid floors and the pipework runs in
the loft and down the walls to the rads. These 2 rads are served by
the one pair of pipes until they reach skirting board level where
they are teed off to one rad in the lounge and the other through the
wall to the hall.
The tank is an old style primatic, central heating and domestic hot
water in the same tank, separated by an air pocket - but it seems to
work ok for all the other rads.
The valves are all new (one of them is thermostatic) - it seems a bit
unlikely that 2 of them would be blocked. The system has recently been
drained and flushed before they were fitted.
Any suggestions please?

Sounds like you got an air-lock in one or other pipe - stopping any
circulation. Bleeding them with both radiator valves open won't cure this,
because water will come via the non-air-locked pipe. You need to turn off
each radiator valve in turn, and bleed a couple of litres of water out each
time. That should ensure that *both* pipes are full of water.
--
Cheers,
Roger
______
Please reply to newsgroup.
Reply address IS valid, but is disposable in the event of excessive
spam.

On Tue, 31 Jan 2006 12:08:54 -0800, rob wrote:

I've just had a plumber fit 2 new bigger radiators to replace 2 old
ones. The system was drained then refilled- all the other rads are OK
but the 2 new ones won't heat up at all.
We tried everything we could think of.
Bled the air out - they are full of water.
Turned all the other rads off and ran the pump.
Put a hose on the drain cocks that are fitted to both rads and ran
the water through till it was hot. Closed the drain cocks but no
hot water into the rads.
The property is a bungalow with solid floors and the pipework runs in
the loft and down the walls to the rads. These 2 rads are served by the
one pair of pipes until they reach skirting board level where they are
teed off to one rad in the lounge and the other through the wall to the
hall.
The tank is an old style primatic, central heating and domestic hot
water in the same tank, separated by an air pocket - but it seems to
work ok for all the other rads.
The valves are all new (one of them is thermostatic) - it seems a bit
unlikely that 2 of them would be blocked. The system has recently been
drained and flushed before they were fitted.
Any suggestions please?

The obvious one, which seeing you have not said, is whether _both_ valves
on both the rads are open.


--
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
Choosing a Boiler FAQ http://www.makewrite.demon.co.uk/BoilerChoice.html

Roger Mills (aka Set Square) wrote:

So how come you have "decloaked" then? ;-)


--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/

"Ed Sirett" wrote in message
news
On Tue, 31 Jan 2006 12:08:54 -0800, rob wrote:

I've just had a plumber fit 2 new bigger radiators to replace 2 old
ones. The system was drained then refilled- all the other rads are OK
but the 2 new ones won't heat up at all.
We tried everything we could think of.
Bled the air out - they are full of water.
Turned all the other rads off and ran the pump.
Put a hose on the drain cocks that are fitted to both rads and ran
the water through till it was hot. Closed the drain cocks but no
hot water into the rads.
The property is a bungalow with solid floors and the pipework runs in
the loft and down the walls to the rads. These 2 rads are served by the
one pair of pipes until they reach skirting board level where they are
teed off to one rad in the lounge and the other through the wall to the
hall.
The tank is an old style primatic, central heating and domestic hot
water in the same tank, separated by an air pocket - but it seems to
work ok for all the other rads.
The valves are all new (one of them is thermostatic) - it seems a bit
unlikely that 2 of them would be blocked. The system has recently been
drained and flushed before they were fitted.
Any suggestions please?

The obvious one, which seeing you have not said, is whether _both_ valves
on both the rads are open.


The obvious one which neither of you have said is......GET THE PLUMBER
BACK!! I presume you paid him for the job so why are you trying to sort it
out?

HTH

John

Thanks Roger - I will try your suggestion

In an earlier contribution to this discussion,
John Rumm wrote:

Roger Mills (aka Set Square) wrote:

So how come you have "decloaked" then? ;-)


How do you know that I have? g
--
Cheers,
Roger
______
Please reply to newsgroup.
Reply address IS valid, but is disposable in the event of excessive
spam.