Hi all,

I've got a British Gas boiler, Model 50F2 (made by Potterton).

When I try to put the radiators on - nothing happens. When I try to
put the hot water on - both the hot water and radiators come on. The
boiler is 7 years old and the problem has just started, is there
something sticking?

Any help would be much appreciated.

Thanks,

Iain.

"iain_b" wrote in message
ups.com...
Hi all,

I've got a British Gas boiler, Model 50F2 (made by Potterton).

When I try to put the radiators on - nothing happens. When I try to
put the hot water on - both the hot water and radiators come on. The
boiler is 7 years old and the problem has just started, is there
something sticking?

Not necessarily the only answer but the symptoms can be explained by a
faulty heating zone valve, either synchron motor or microswitch.

Jim A

In an earlier contribution to this discussion,
iain_b wrote:

Hi all,

I've got a British Gas boiler, Model 50F2 (made by Potterton).

When I try to put the radiators on - nothing happens. When I try to
put the hot water on - both the hot water and radiators come on. The
boiler is 7 years old and the problem has just started, is there
something sticking?

Any help would be much appreciated.

Thanks,

Iain.

It's unlikely to be a boiler problem per se. The boiler obviously works, or
it wouldn't do anything when both HW and CH are turned on. The problem is
likely to be in the external controls - motorised valves, thermostats, etc.
What type of system have you got? Have a look at
http://content.honeywell.com/uk/homes/systems.htm and see whether your
system conforms to one or other of the standard 'plans'. If you tell us
which one, we'll tell you what to look for.
--
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 17 Sep, 13:11, "Jim Alexander" wrote:
"iain_b" wrote in message

ups.com... Hi all,

I've got a British Gas boiler, Model 50F2 (made by Potterton).

When I try to put the radiators on - nothing happens. When I try to
put the hot water on - both the hot water and radiators come on. The
boiler is 7 years old and the problem has just started, is there
something sticking?

Not necessarily the only answer but the symptoms can be explained by a
faulty heating zone valve, either synchron motor or microswitch.

Jim A

Thanks Jim,
Further investigation shows that the boiler doesn't even 'kick in'
when the heating is switched to 'on' and if the boiler is running with
the hot water on then switching the heating to 'on' will switch the
boiler off altogether - is this more likely to be pointing to the
microswitch?

Thanks,
Iain.

On 17 Sep, 13:29, "Roger Mills" wrote:
In an earlier contribution to this discussion,

iain_b wrote:
Hi all,

I've got a British Gas boiler, Model 50F2 (made by Potterton).

When I try to put the radiators on - nothing happens. When I try to
put the hot water on - both the hot water and radiators come on. The
boiler is 7 years old and the problem has just started, is there
something sticking?

Any help would be much appreciated.

Thanks,

Iain.

It's unlikely to be a boiler problem per se. The boiler obviously works, or
it wouldn't do anything when both HW and CH are turned on. The problem is
likely to be in the external controls - motorised valves, thermostats, etc.
What type of system have you got? Have a look athttp://content.honeywell.com/uk/homes/systems.htmand see whether your
system conforms to one or other of the standard 'plans'. If you tell us
which one, we'll tell you what to look for.
--
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!

Thanks Roger,

Further investigation shows that I've got the S plan system - I think.
Also turning the heating to 'on' won't start the boiler and if the
boiler is on with the hot water control, turning the heating to 'on'
will switch off the boiler altogether, I'm confused.

Thanks,

Iain.

"iain_b" wrote in message
oups.com...
On 17 Sep, 13:11, "Jim Alexander" wrote:
"iain_b" wrote in message

ups.com... Hi all,

I've got a British Gas boiler, Model 50F2 (made by Potterton).

When I try to put the radiators on - nothing happens. When I try to
put the hot water on - both the hot water and radiators come on. The
boiler is 7 years old and the problem has just started, is there
something sticking?

Not necessarily the only answer but the symptoms can be explained by a
faulty heating zone valve, either synchron motor or microswitch.

Jim A

Thanks Jim,
Further investigation shows that the boiler doesn't even 'kick in'
when the heating is switched to 'on' and if the boiler is running with
the hot water on then switching the heating to 'on' will switch the
boiler off altogether - is this more likely to be pointing to the
microswitch?

Firstly you need to post whether you have 2 x 2 port zone valves or 1 x 3
port. From your description of the fault guessing 3 port.

Jim A

In an earlier contribution to this discussion,
iain_b wrote:

Thanks Roger,

Further investigation shows that I've got the S plan system - I think.
Also turning the heating to 'on' won't start the boiler and if the
boiler is on with the hot water control, turning the heating to 'on'
will switch off the boiler altogether, I'm confused.

Thanks,

Iain.

You ain't the only one!

Correctly functioning S-Plan systems will run the boiler whenever either or
both HW and CH are calling for heat, and turning on one won't stop the
other!

Has any work been done on the system recently - particularly replacing one
of the motorised valves (or just its actuator)? I can't explain the symptoms
unless there's a wiring fault, and even so, you'd have to be quite
'clever'[1] to produce this particular effect.

[1] The secondary switches on the valve actuators are supposed to be wired
in parallel. To get this effect, you'd have to wire them in series *and* use
the NO contact on one and the NC contact on the other!

--
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 18 Sep, 13:52, "Roger Mills" wrote:
In an earlier contribution to this discussion,

iain_b wrote:
Thanks Roger,

Further investigation shows that I've got the S plan system - I think.
Also turning the heating to 'on' won't start theboilerand if the
boileris on with the hot water control, turning the heating to 'on'
will switch off theboileraltogether, I'm confused.

Thanks,

Iain.

You ain't the only one!

Correctly functioning S-Plan systems will run theboilerwhenever either or
both HW and CH are calling for heat, and turning on one won't stop the
other!

Has any work been done on the system recently - particularly replacing one
of the motorised valves (or just its actuator)? I can't explain the symptoms
unless there's a wiring fault, and even so, you'd have to be quite
'clever'[1] to produce this particular effect.

[1] The secondary switches on the valve actuators are supposed to be wired
in parallel. To get this effect, you'd have to wire them in series *and* use
the NO contact on one and the NC contact on the other!

--
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!

Hi Roger,

No work has been done on the system.
I'm now totally confused - both the hot water and heating are in the
'off'' position on the controller, but the boiler is still working -
I'm guessing that the controller's internal circuits are goosed and
hopefully a new controller will fix things. It's a British Gas UP1
controller, any ideas where I can get such a thing - I take it it will
be a Honeywell or similar re-badged.

Thanks,

Iain.

On 18 Sep, 12:11, "Jim Alexander" wrote:
"iain_b" wrote in message

oups.com...



On 17 Sep, 13:11, "Jim Alexander" wrote:
"iain_b" wrote in message

roups.com... Hi all,

I've got a British Gasboiler, Model 50F2 (made by Potterton).

When I try to put the radiators on - nothing happens. When I try to
put the hot water on - both the hot water and radiators come on. The
boileris 7 years old and the problem has just started, is there
something sticking?

Not necessarily the only answer but the symptoms can be explained by a
faulty heating zone valve, either synchron motor or microswitch.

Jim A

Thanks Jim,
Further investigation shows that theboilerdoesn't even 'kick in'
when the heating is switched to 'on' and if theboileris running with
the hot water on then switching the heating to 'on' will switch the
boileroff altogether - is this more likely to be pointing to the
microswitch?

Firstly you need to post whether you have 2 x 2 port zone valves or 1 x 3
port. From your description of the fault guessing 3 port.

Jim A- Hide quoted text -

- Show quoted text -

Hi Jim,

There are 2 motorized valves in the system.
Now the boiler switches on and stays on even if both hot water and
heating are in the 'off' position - is it likely that the wall
controller is faulty? It's a Britisg Gas UP1 controller, is this
likely to be a Honeywell or similar and any ideas where I could get
one?

Thanks,

Iain.

In an earlier contribution to this discussion,
iain_b wrote:


Hi Roger,

No work has been done on the system.
I'm now totally confused - both the hot water and heating are in the
'off'' position on the controller, but the boiler is still working -
I'm guessing that the controller's internal circuits are goosed and
hopefully a new controller will fix things. It's a British Gas UP1
controller, any ideas where I can get such a thing - I take it it will
be a Honeywell or similar re-badged.


No, there's a more likely explanation than a duff controller.

An S-Plan system works like this:
The controller and room stat control the CH zone valve.
The controller and cylinder stat control the HW zone valve.
Each zone valve has a secondary switch in its actuator which is electrically
isolated from the motor circuit, and which makes when the valve is fully
open.
These secondary switches have a permanent live input (independent of
anything the controller or stats are doing) and their outputs feed the
boiler and pump.
[If you study the S-Plan wiring diagram in
http://content.honeywell.com/uk/homes/systems.htm you'll see what I mean]

If one of the valves sticks open (or if its secondary contacts weld closed)
the boiler and pump will run even when everything is switched off. You need
to have a close look at these valves!
--
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 20 Sep, 10:47, "Roger Mills" wrote:
In an earlier contribution to this discussion,

iain_b wrote:

Hi Roger,

No work has been done on the system.
I'm now totally confused - both the hot water and heating are in the
'off'' position on the controller, but theboileris still working -
I'm guessing that the controller's internal circuits are goosed and
hopefully a new controller will fix things. It's a British Gas UP1
controller, any ideas where I can get such a thing - I take it it will
be a Honeywell or similar re-badged.

No, there's a more likely explanation than a duff controller.

An S-Plan system works like this:
The controller and room stat control the CH zone valve.
The controller and cylinder stat control the HW zone valve.
Each zone valve has a secondary switch in its actuator which is electrically
isolated from the motor circuit, and which makes when the valve is fully
open.
These secondary switches have a permanent live input (independent of
anything the controller or stats are doing) and their outputs feed theboilerand pump.
[If you study the S-Plan wiring diagram inhttp://content.honeywell.com/uk/homes/systems.htmyou'll see what I mean]

If one of the valves sticks open (or if its secondary contacts weld closed)
theboilerand pump will run even when everything is switched off. You need
to have a close look at these valves!
--
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!

Roger,

I checked the valves and the heating one was stuck, working it open
and shut with a spanner and a wee bit of WD40 loosened it off
completely, did the hot water one too for good measure. Everything is
working properly now. Thanks very much for all your help - this
central heating novice (could you tell?) was totally lost.

Cheers,

Iain.

On 18 Sep, 12:11, "Jim Alexander" wrote:
"iain_b" wrote in message

oups.com...



On 17 Sep, 13:11, "Jim Alexander" wrote:
"iain_b" wrote in message

roups.com... Hi all,

I've got a British Gasboiler, Model 50F2 (made by Potterton).

When I try to put the radiators on - nothing happens. When I try to
put the hot water on - both the hot water and radiators come on. The
boileris 7 years old and the problem has just started, is there
something sticking?

Not necessarily the only answer but the symptoms can be explained by a
faulty heating zone valve, either synchron motor or microswitch.

Jim A

Thanks Jim,
Further investigation shows that theboilerdoesn't even 'kick in'
when the heating is switched to 'on' and if theboileris running with
the hot water on then switching the heating to 'on' will switch the
boileroff altogether - is this more likely to be pointing to the
microswitch?

Firstly you need to post whether you have 2 x 2 port zone valves or 1 x 3
port. From your description of the fault guessing 3 port.

Jim A- Hide quoted text -

- Show quoted text -

Jim,

System fixed, the heating valve was stuck.

Thanks,

Iain.

iain_b wrote:
On 20 Sep, 10:47, "Roger Mills" wrote:
In an earlier contribution to this discussion,

iain_b wrote:

Hi Roger,
No work has been done on the system.
I'm now totally confused - both the hot water and heating are in the
'off'' position on the controller, but theboileris still working -
I'm guessing that the controller's internal circuits are goosed and
hopefully a new controller will fix things. It's a British Gas UP1
controller, any ideas where I can get such a thing - I take it it will
be a Honeywell or similar re-badged.
No, there's a more likely explanation than a duff controller.

An S-Plan system works like this:
The controller and room stat control the CH zone valve.
The controller and cylinder stat control the HW zone valve.
Each zone valve has a secondary switch in its actuator which is electrically
isolated from the motor circuit, and which makes when the valve is fully
open.
These secondary switches have a permanent live input (independent of
anything the controller or stats are doing) and their outputs feed theboilerand pump.
[If you study the S-Plan wiring diagram inhttp://content.honeywell.com/uk/homes/systems.htmyou'll see what I mean]

If one of the valves sticks open (or if its secondary contacts weld closed)
theboilerand pump will run even when everything is switched off. You need
to have a close look at these valves!
--
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!

Roger,

I checked the valves and the heating one was stuck, working it open
and shut with a spanner and a wee bit of WD40 loosened it off
completely, did the hot water one too for good measure. Everything is
working properly now. Thanks very much for all your help - this
central heating novice (could you tell?) was totally lost.


Be advised that once they stick once, they tend to do so again with
increasing frequency until they are irreperable.

Schedule a replacement for a quiet day next summer, and get the part in
now in case you need t do it on an icy Sunday morning in winter..


Cheers,

Iain.