Hi all,

Just hoping you guys can give me some help on my central heating
system. I am having issues with the radiators not heating. I have hot
water, the boiler fires and the pump appears to be working.

The system is a conventional setup, with the tank in the loft space.
It would appear that the radiator in the bathroom is the only one
working, but I assume this is the way it was designed so I have warm
towels.

The thermostat has been turned right up and this hasn't helped. I have
also bled most of the radiators (will do the rest this evening). All
the pipes surrounding the water tank are hot with the exception off
one. However it appears that one other is warm (as it is near the
pump) and appears to run downstairs, but gets colder further down the
pipe (this could be the water return pipe. I have checked all radiator
pipes and they are all stone cold! Could it be the switching valve?

I'm not sure whether the switching valve is the following: its a white
box with two lights on it both of which illuminate when the CH and HW
are on. Could it be that this is the fault? Like I say I've no idea
what else this could be other than the valve.

The bolier is a Potterton Suprima 30 is this helps. (Had to have the
PCB change cos of the famous lock out issue).

Any help would be appreciated.

Thanks,

Mark

Sparky wrote:

I'm not sure whether the switching valve is the following: its a white
box with two lights on it both of which illuminate when the CH and HW
are on. Could it be that this is the fault? Like I say I've no idea
what else this could be other than the valve.

Is there a lever on the valve ? Try applying the lever. If the heating
starts coming up then that is your problem, likely the valve head needs
replaced.

It's weird that your bathroom radiator is heating up. That suggests it
is on the same circuit as the hot water, and one of the other radiators
is the bypass. Of all the radiators in the house, which ones do not have
TRVs ?

"Sparky" wrote


The system is a conventional setup, with the tank in the loft space.
It would appear that the radiator in the bathroom is the only one
working, but I assume this is the way it was designed so I have warm
towels.

snip...........

How old is the system?
Look around the airing cupboard or wherever the pump is located and try to
trace the piping from the pump.
You are likely to find either a three way valve (flow from pump and
discharge to either hot water, heating or both)
OR
two 2 way valves also controlling water to hw cylinder or heating ciruit.

If you are getting no (or very little heating) it is possible that the 3-way
valve (or the two way leading to your heating circuit) has failed.
Try to confirm this by turning on/off room thermostat and check for valve
activity and pipe temperature.
Try altering the hw tank stat first so you know what to expect when demand
in on/off.

Phil

On Thu, 15 Mar 2007 07:29:35 -0700, Sparky wrote:

Any help would be appreciated.

http://wiki.diyfaq.org.uk/index.php?...entral_Heating

Hi mark, sounds like the diverter valve has gone, this is either a silver, white or blue box which has 3 pipes connected to it soundz like it is possibly seized. Hope this helps! approximate time to replace one is an hour.

Hi all,

I got in last night after doing some web research yesterday and went
straight to the 3 way valve. I placed in onto manual override and
bingo the one cold pipe warmed up instantly followed by the rads. I
let it heat up for an hour or so like this before returning the
setting to auto. Left it on and still had heating. I then switched the
heating off, let it all cool down and restarted the system, again
worked perfectly. Tried it again this morning before leaving for work
and yep its still going. The motor must of got jammed or something in
the valve. I'm now a happy chappie.

Thanks for all your comments guys, all of which were spot on. I
appreciate the quick responses.

Just out of interest. The 3 way valve in question is a Myson Power
Extra. Any idea on the cost for one of these little babies, just in
case it does need replacing?.

Cheers and thanks again,

Mark

On 15 Mar, 20:50, richwoodblue
wrote:
Sparky Wrote:





Hi all,

Just hoping you guys can give me some help on my central heating
system. I am having issues with the radiators not heating. I have hot
water, the boiler fires and the pump appears to be working.

The system is a conventional setup, with the tank in the loft space.
It would appear that the radiator in the bathroom is the only one
working, but I assume this is the way it was designed so I have warm
towels.

The thermostat has been turned right up and this hasn't helped. I have
also bled most of the radiators (will do the rest this evening). All
the pipes surrounding the water tank are hot with the exception off
one. However it appears that one other is warm (as it is near the
pump) and appears to run downstairs, but gets colder further down the
pipe (this could be the water return pipe. I have checked all radiator
pipes and they are all stone cold! Could it be the switching valve?

I'm not sure whether the switching valve is the following: its a white
box with two lights on it both of which illuminate when the CH and HW
are on. Could it be that this is the fault? Like I say I've no idea
what else this could be other than the valve.

The bolier is a Potterton Suprima 30 is this helps. (Had to have the
PCB change cos of the famous lock out issue).

Any help would be appreciated.

Thanks,

Mark

Hi mark, sounds like the diverter valve has gone, this is either a
silver, white or blue box which has 3 pipes connected to it soundz like
it is possibly seized. Hope this helps! approximate time to replace one
is an hour.

--
richwoodblue- Hide quoted text -

- Show quoted text -

In an earlier contribution to this discussion,
Sparky wrote:

Hi all,

I got in last night after doing some web research yesterday and went
straight to the 3 way valve. I placed in onto manual override and
bingo the one cold pipe warmed up instantly followed by the rads. I
let it heat up for an hour or so like this before returning the
setting to auto. Left it on and still had heating. I then switched the
heating off, let it all cool down and restarted the system, again
worked perfectly. Tried it again this morning before leaving for work
and yep its still going. The motor must of got jammed or something in
the valve. I'm now a happy chappie.

Thanks for all your comments guys, all of which were spot on. I
appreciate the quick responses.

Just out of interest. The 3 way valve in question is a Myson Power
Extra. Any idea on the cost for one of these little babies, just in
case it does need replacing?.

Cheers and thanks again,

Mark


It's more likely that the wet part of the valve had stuck and that moving it
with the manual lever freed it.

If you *do* need to replace the valve, it doesn't necessarily have to be a
Myson - there are lots which do the same job. For example, Screwfix do a
Horstmann valve for £38, a Danfoss for £50, a Drayton for £65 and a
Honeywell for £70.

In cases where the actuator (the electrical bit rather than the wet bit) is
faulty, you can usually replace just that bit without any need to drain the
system - but I don't think that applies in your case. [You can even replace
just the motor for about a tenner in many actuators].

If you get any further problems, it would be worth unbolting the actuator
from the valve (but don't disconnect the electrics)and turning the valve
spindle back and forth a few times to make sure that it moves freely.
--
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!

In message . com,
Sparky writes
I got in last night after doing some web research yesterday and went
straight to the 3 way valve. I placed in onto manual override and bingo
the one cold pipe warmed up instantly followed by the rads. I let it
heat up for an hour or so like this before returning the setting to
auto. Left it on and still had heating. I then switched the heating
off, let it all cool down and restarted the system, again worked
perfectly. Tried it again this morning before leaving for work and yep
its still going. The motor must of got jammed or something in the
valve. I'm now a happy chappie.

Those hideous little valves are a balancing job between a spring, a
motor, a diode and some resistors. It's very easy for them to get stuck
on the tiniest spec of dirt or just anything really. That's assuming
the motor doesn't pop it's clogs because it spends most of it's working
life in a stalled state.

I wonder how many of these valves are sitting with an elastic band
holding them in their bypass mode on a permanent basis.

--
Clive Mitchell
http://www.bigclive.com

In message , Roger Mills
writes
If you *do* need to replace the valve, it doesn't necessarily have to
be a Myson - there are lots which do the same job. For example,
Screwfix do a Horstmann valve for £38, a Danfoss for £50, a Drayton for
£65 and a Honeywell for £70.

Have they genuinely standardised on the wire colour for these
components?

--
Clive Mitchell
http://www.bigclive.com

On Fri, 16 Mar 2007 12:19:32 GMT, Clive Mitchell
wrote:

|!In message , Roger Mills
writes
|!If you *do* need to replace the valve, it doesn't necessarily have to
|!be a Myson - there are lots which do the same job. For example,
|!Screwfix do a Horstmann valve for ?38, a Danfoss for ?50, a Drayton for
|!?65 and a Honeywell for ?70.
|!
|!Have they genuinely standardised on the wire colour for these
|!components?

I just bought a new valve, and the colours were much the same as the one
which I b*gg*r*d up.
--
Dave Fawthrop sf hyphenologist.co.uk 165 *Free* SF ebooks.
165 Sci Fi books on CDROM, from Project Gutenberg
http://www.gutenberg.org/wiki/Main_Page Completely Free to any
address in the UK. Contact me on the *above* email address.

In an earlier contribution to this discussion,
Clive Mitchell wrote:

In message , Roger Mills
writes
If you *do* need to replace the valve, it doesn't necessarily have to
be a Myson - there are lots which do the same job. For example,
Screwfix do a Horstmann valve for £38, a Danfoss for £50, a Drayton
for £65 and a Honeywell for £70.

Have they genuinely standardised on the wire colour for these
components?

I believe so - as long as you get the right *spec* of valve. So all 3-port
mid-position valves should be the same, but will differ from pure diverter
valves - which have no useable mid position. Similarly with 2-port valves,
of which there are several flavours depending on whether they have
auxilliary contacts and if so, whether the contacts are on/off or
change-over. But, for a given flavour, the wiring should be the same,
regardless of make.
--
Cheers,
Roger
______
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monitored.. Messages sent to it may not be read for several weeks.
PLEASE REPLY TO NEWSGROUP!

On Fri, 16 Mar 2007 15:17:35 +0000, Roger Mills wrote:

I believe so - as long as you get the right *spec* of valve. So all
3-port mid-position valves should be the same,

most, not all - see
http://wiki.diyfaq.org.uk/index.php?...otorised_Valve

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

On Fri, 16 Mar 2007 15:17:35 +0000, Roger Mills wrote:

I believe so - as long as you get the right *spec* of valve. So all
3-port mid-position valves should be the same,

most, not all - see
http://wiki.diyfaq.org.uk/index.php?...otorised_Valve

If you mean spring return valves vs non-spring return, I agree.

However, my understanding is that non-spring return valves are relatively
uncommon in domestic situations.
--
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!

On Fri, 16 Mar 2007 21:41:54 +0000, Roger Mills wrote:

If you mean spring return valves vs non-spring return, I agree.

However, my understanding is that non-spring return valves are relatively
uncommon in domestic situations.

True statistically overall, but if you happen to have one on your system
they're 100% common for you! Point being it's best to check before
assuming you can just replace it with any old spring-return valve (been
there, done that :-()

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

On Fri, 16 Mar 2007 21:41:54 +0000, Roger Mills wrote:

If you mean spring return valves vs non-spring return, I agree.

However, my understanding is that non-spring return valves are
relatively uncommon in domestic situations.

True statistically overall, but if you happen to have one on your
system they're 100% common for you! Point being it's best to check
before assuming you can just replace it with any old spring-return
valve (been there, done that :-()

Yes, that's true. I plead guilty as charged of failing to mention the
non-spring return variety.
--
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!

On Sat, 17 Mar 2007 10:08:20 +0000, Roger Mills wrote:

Yes, that's true. I plead guilty as charged of failing to mention the
non-spring return variety.

That's better! I sentence you to rewire a Y-plan system from a fully
motorised to spring return where all the wiring is connected with
individual chock-block segments crammed into the back of the single
pattress of the FCU which is located at the back of the airing cupboard ;-)

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

On Sat, 17 Mar 2007 10:08:20 +0000, Roger Mills wrote:

Yes, that's true. I plead guilty as charged of failing to mention the
non-spring return variety.

That's better! I sentence you to rewire a Y-plan system from a fully
motorised to spring return where all the wiring is connected with
individual chock-block segments crammed into the back of the single
pattress of the FCU which is located at the back of the airing
cupboard ;-)

Ugh! Do I have the option of a custodial sentence instead? g
--
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!

On Sat, 17 Mar 2007 12:52:52 +0000, John Stumbles wrote:

On Sat, 17 Mar 2007 10:08:20 +0000, Roger Mills wrote:

Yes, that's true. I plead guilty as charged of failing to mention the
non-spring return variety.

That's better! I sentence you to rewire a Y-plan system from a fully
motorised to spring return where all the wiring is connected with
individual chock-block segments crammed into the back of the single
pattress of the FCU which is located at the back of the airing cupboard ;-)


That's exactly the job I was faced with last autumn.
It became very clear that if I and my apprentice were going to get home
starting from scratch with a double-gang wiring centre was the only way.




--
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