I have an old Servowarm Elite 50 Central heating boiler and the pump
failed. I have replaced the pump but the Pump does not shut down when
the boiler turns off.

Does anyone know, if I purchase a new programmer, if this has the pump
overrun facility on it or do I have to find the fault, "solenoid or
relay?" in the original Timer/programmer.

Thanks




--
Nigel Hewer

In article ,
Nigel Hewer wrote:
I have an old Servowarm Elite 50 Central heating boiler and the pump
failed. I have replaced the pump but the Pump does not shut down when
the boiler turns off.

Do you mean when the boiler is switched off by the programmer? Older
systems will often have the pump running while the boiler cycles. On those
the two aren't really interdependent - the pump is controlled by the room
stat while the boiler by its own.

Does anyone know, if I purchase a new programmer, if this has the pump
overrun facility on it or do I have to find the fault, "solenoid or
relay?" in the original Timer/programmer.

Pump overrun devices are usually part of the boiler rather than programmer.

Of course Servowarm tended to have a mind of their own. ;-)

--
*Do they ever shut up on your planet?

Dave Plowman London SW
To e-mail, change noise into sound.

Nigel Hewer wrote:
I have an old Servowarm Elite 50 Central heating boiler and the pump
failed. I have replaced the pump but the Pump does not shut down when
the boiler turns off.

Does anyone know, if I purchase a new programmer, if this has the pump
overrun facility on it or do I have to find the fault, "solenoid or
relay?" in the original Timer/programmer.

Thanks




--
Nigel Hewer

My room stat controls the pump only and the boiler is controlled by
it's own stat. If the boiler stat has shut off the boiler and the room
stat is calling for heat the pump continues to run.

wrote:

My room stat controls the pump only and the boiler is controlled by
it's own stat. If the boiler stat has shut off the boiler and the room
stat is calling for heat the pump continues to run.

So the pump stops allowing the boiler to heat really quickly and then
shut itself off ? That sounds very dodgy indeed. My boiler would
shutdown and require resetting if I were to do that.

Geronimo W. Christ Esq wrote:
wrote:

My room stat controls the pump only and the boiler is controlled by
it's own stat. If the boiler stat has shut off the boiler and the room
stat is calling for heat the pump continues to run.

So the pump stops allowing the boiler to heat really quickly and then
shut itself off ? That sounds very dodgy indeed. My boiler would
shutdown and require resetting if I were to do that.

Quite a common arrangement for older systems. When the heating demand
is satisfied the pump is switched off by the roomstat and the boiler
then continues to run until the water temperature in the boiler rises
high enough for the boiler stat to shut it off. Conversely if the
boiler water temperature reaches the boiler stat setting before the
heating load is satisfied the pump will continue to run although the
boiler has shut off. In fact some vintage heating systems have no
roomstat at all and the heating is controlled by the boiler stat alone.

In article ,
"Geronimo W. Christ Esq" writes:
wrote:

My room stat controls the pump only and the boiler is controlled by
it's own stat. If the boiler stat has shut off the boiler and the room
stat is calling for heat the pump continues to run.

So the pump stops allowing the boiler to heat really quickly and then
shut itself off ? That sounds very dodgy indeed.

Depends on the boiler's water content, and this was the norm
with higher water content boilers.

--
Andrew Gabriel

On Sun, 26 Nov 2006 10:17:45 +0000, Dave Plowman (News) wrote:

In article ,
Nigel Hewer wrote:
I have an old Servowarm Elite 50 Central heating boiler and the pump
failed. I have replaced the pump but the Pump does not shut down when
the boiler turns off.

Do you mean when the boiler is switched off by the programmer? Older
systems will often have the pump running while the boiler cycles. On those
the two aren't really interdependent - the pump is controlled by the room
stat while the boiler by its own.

Does anyone know, if I purchase a new programmer, if this has the pump
overrun facility on it or do I have to find the fault, "solenoid or
relay?" in the original Timer/programmer.

Pump overrun devices are usually part of the boiler rather than programmer.

Of course Servowarm tended to have a mind of their own. ;-)


They were (are?) specialists in rebadging and used reasonable kit from
major manufactuers including Aqualisa shower mixers.
My wild guess is that this might be a rebadged Ideal Elite such a boiler
could well have an overrun implemented as a simple temperture sensitive
changeover switch. It has become stuck in the hot over-run position.

--
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
Gas Fitting Standards Docs he http://www.makewrite.demon.co.uk/GasFittingStandards

In message , "Dave Plowman (News)"
writes
In article ,
Nigel Hewer wrote:
I have an old Servowarm Elite 50 Central heating boiler and the pump
failed. I have replaced the pump but the Pump does not shut down when
the boiler turns off.

Do you mean when the boiler is switched off by the programmer? Older
systems will often have the pump running while the boiler cycles. On those
the two aren't really interdependent - the pump is controlled by the room
stat while the boiler by its own.

Does anyone know, if I purchase a new programmer, if this has the pump
overrun facility on it or do I have to find the fault, "solenoid or
relay?" in the original Timer/programmer.

Pump overrun devices are usually part of the boiler rather than programmer.

Of course Servowarm tended to have a mind of their own. ;-)

I'm just wondering if his timer is a Horstman 424 - one version of which
(the emerald?) had a bimetalic pump overrun integrated into it

OP - you are just going to have to dig in a bit deeper and have a look


--
geoff

raden Wrote:
In message , "Dave Plowman (News)"
writes-
In article ,
Nigel Hewer
wrote:-
I have an old Servowarm Elite 50 Central heating boiler and the pump
failed. I have replaced the pump but the Pump does not shut down when
the boiler turns off.-

Do you mean when the boiler is switched off by the programmer? Older
systems will often have the pump running while the boiler cycles. On
those
the two aren't really interdependent - the pump is controlled by the
room
stat while the boiler by its own.
-
Does anyone know, if I purchase a new programmer, if this has the
pump
overrun facility on it or do I have to find the fault, "solenoid or
relay?" in the original Timer/programmer.-

Pump overrun devices are usually part of the boiler rather than
programmer.

Of course Servowarm tended to have a mind of their own. ;-)
-
I'm just wondering if his timer is a Horstman 424 - one version of
which
(the emerald?) had a bimetalic pump overrun integrated into it

OP - you are just going to have to dig in a bit deeper and have a look


--
geoff


Thanks for everyones comments.

My system does not have a room stat and on closer inspection of the
timeclock have noticed a bi-metallic strip that is broken (thanks
geoff) Could I replace this or replace the timeclock? Any ideas where I
might get one?

Regards
Nigel




--
Nigel Hewer

In message , Nigel
Hewer writes

Pump overrun devices are usually part of the boiler rather than
programmer.
Of course Servowarm tended to have a mind of their own. ;-)
I'm just wondering if his timer is a Horstman 424 - one version of
which
(the emerald?) had a bimetalic pump overrun integrated into it
Thanks for everyones comments.
My system does not have a room stat and on closer inspection of the
timeclock have noticed a bi-metallic strip that is broken (thanks
geoff) Could I replace this or replace the timeclock? Any ideas where I
might get one?



If there had been one person in the UK who might have had one, it would
have been me

I don't

You are (as they say) buggered

there are some solutions, but you're better off being told by one of the
fitters who frequent this NG


--
geoff