Central Heating Proble, pump running when all controls off, helpplease
 

Background info:
Potterton Suprima 80 boiler 5 yr old
Honeywell Timer St6400
Honeywell 3 way valve V 4073A 1039
Pump Grunfos Selectric UPS 15-50
wired to Y plan
normal operation allows separate H/water from Heating or both together
all rads have thermostats

Problem:
Central Heating and water both switched off at timer yet yesterday
evening the pump was running and continued to run until we slightly
turn the white control anti-clock on the side of the Grunfos pump, the
pump then stops running.
Switch the Honeywell timer to hot water the boiler lights up but the
pump does NOT operate until we turn the white control back slightly
clockwise to the 90* setting mark on the pump.
So is this another 3 way valve issue or the pump not receiving the
correct signal ?

Any ideas or suggestion most welcome, some years ago we were able to
replace the 3 way valve after good advice from Roger Mills.

Happy to provide more info if required.
Steve

Central Heating Proble, pump running when all controls off, helpplease
 

Central Heating Proble, pump running when all controls off, helpplease
 

On Jun 6, 10:55*am, The Natural Philosopher
wrote:
wrote:
Background info:
Potterton *Suprima 80 boiler 5 yr old
Honeywell Timer St6400
Honeywell 3 way valve V 4073A 1039
Pump Grunfos Selectric UPS 15-50
wired to Y plan
normal operation allows separate H/water from Heating or both together
all rads have thermostats

Problem:
Central Heating and water both switched off at timer yet yesterday
evening the pump was running and continued to run until we slightly
turn the white control anti-clock on the side of the Grunfos pump, the
pump then stops running.
Switch the Honeywell timer to hot water the boiler lights up but the
pump does NOT operate until we turn the white control back slightly
clockwise to the 90* setting mark on the pump.
So is this another 3 way valve issue or the pump not receiving the
correct signal ?

Any ideas or suggestion most welcome, some years ago we were able to
replace the 3 way valve after good advice from Roger Mills.

That is almost certainly a stuck 3 way switch.

The heating timers and thermostats control the motorised valve, and the
valve itself controls the pump.

See if the valve is moveable by hand, if it is, and this fixes the
problem temporarily, the motor may have burned out. If its seized, you
will need to dismantle it and try and free it by turning the thing with
a wrench. Sometimes crud gets in and jams them but you can free them.

In extreme cases its a drain down or isolate, and a new valve..

Happy to provide more info if required.
Steve

Thanks for your swift response, just some other info, we put the hot
water on this morning for 1hr on the Timer, then reset the white
control on the Grunfos pump and when the cycle of 1hr finished we had
hot water and the pump has stopped runningie back to 'normal' function
We don't want to buy one around £60.00 if this is not the mosyt likely
fault.

Does this still sound like a sticking 3 way valve?,

Central Heating Proble, pump running when all controls off, help please
 

wrote in message
...
Background info:
Potterton Suprima 80 boiler 5 yr old
Honeywell Timer St6400
Honeywell 3 way valve V 4073A 1039
Pump Grunfos Selectric UPS 15-50
wired to Y plan
normal operation allows separate H/water from Heating or both together
all rads have thermostats

Problem:
Central Heating and water both switched off at timer yet yesterday
evening the pump was running and continued to run until we slightly
turn the white control anti-clock on the side of the Grunfos pump, the
pump then stops running.
Switch the Honeywell timer to hot water the boiler lights up but the
pump does NOT operate until we turn the white control back slightly
clockwise to the 90* setting mark on the pump.
So is this another 3 way valve issue or the pump not receiving the
correct signal ?

Any ideas or suggestion most welcome, some years ago we were able to
replace the 3 way valve after good advice from Roger Mills.

Happy to provide more info if required.
Steve

Could be a sticky 3 port. Switch off mains going to boiler and check the
manual arm on the valve head, if you can push it side to side with no
resistance then the valve is jammed. If however there is a strong resistance
and the arm returns automatically when released then the valve is probably
ok.

The symptoms you describe suggest to me that the pump overrun is faulty and
not switching off in which case a new control board would seem to be the
only cure.

The white control on the pump is in fact the pump speed selector and it is
not a good idea to switch off the pump by setting between speeds as this
would allow the boiler to fire up with no circulation and can cause damage
to the boiler.

Central Heating Proble, pump running when all controls off, helpplease
 

On Jun 6, 1:04*pm, "Heliotrope Smith" wrote:
wrote in message

...



Background info:
Potterton *Suprima 80 boiler 5 yr old
Honeywell Timer St6400
Honeywell 3 way valve V 4073A 1039
Pump Grunfos Selectric UPS 15-50
wired to Y plan
normal operation allows separate H/water from Heating or both together
all rads have thermostats

Problem:
Central Heating and water both switched off at timer yet yesterday
evening the pump was running and continued to run until we slightly
turn the white control anti-clock on the side of the Grunfos pump, the
pump then stops running.
Switch the Honeywell timer to hot water the boiler lights up but the
pump does NOT operate until we turn the white control back slightly
clockwise to the 90* setting mark on the pump.
So is this another 3 way valve issue or the pump not receiving the
correct signal ?

Any ideas or suggestion most welcome, some years ago we were able to
replace the 3 way valve after good advice from Roger Mills.

Happy to provide more info if required.
Steve

Could be a sticky 3 port. Switch off mains going to boiler and check the
manual arm on the valve head, if *you can push it side to side with no
resistance then the valve is jammed. If however there is a strong resistance
and the arm returns automatically when released then the valve is probably
ok.

The symptoms you describe suggest to me that the pump overrun is faulty and
not switching off in which case a new *control board would seem to be the
only cure.

*The white control on the pump is in fact the pump speed selector and it is
not a good idea to switch off the pump by setting between speeds as this
would allow the boiler to fire up with no circulation and can cause damage
to the boiler.

Ok here 's the very latest _ the pump stayed back on after the mid day
hot water cycle had finished, so I took the cover off the 3 way valve
and found the earth wire was off inside the 4073A unit , re-attached
the earth wire switched off the circuit tested the value operation as
you suggested and found:
the 4073A 3 way valve lever was in the central position ie the middle,
when I pushed against it to the right there is resistance and then the
lever returned to the centre position [presumably on the return
springs inside the unit]
Does this suggest the valve itself is OK and its just the Honeywell
4073A unit with a malfunction ( this one has been on since 2005).
Hope this piece of info helps with the issue at hand.

PS thanks for the info on the pump itself the speed control seems to
be variable , we just turned it off last night.
I would not leave the cent heating on with the pump speed turned down/
off

Central Heating Proble, pump running when all controls off, help please
 

In an earlier contribution to this discussion,
wrote:

Background info:
Potterton Suprima 80 boiler 5 yr old
Honeywell Timer St6400
Honeywell 3 way valve V 4073A 1039
Pump Grunfos Selectric UPS 15-50
wired to Y plan
normal operation allows separate H/water from Heating or both together
all rads have thermostats

Problem:
Central Heating and water both switched off at timer yet yesterday
evening the pump was running and continued to run until we slightly
turn the white control anti-clock on the side of the Grunfos pump, the
pump then stops running.
Switch the Honeywell timer to hot water the boiler lights up but the
pump does NOT operate until we turn the white control back slightly
clockwise to the 90* setting mark on the pump.
So is this another 3 way valve issue or the pump not receiving the
correct signal ?

Any ideas or suggestion most welcome, some years ago we were able to
replace the 3 way valve after good advice from Roger Mills.

Happy to provide more info if required.
Steve

This is unlikely to be a 3-way valve problem - otherwise the boiler would
fire in addition to the pump running.

You need to check how the pump is wired. Chances are that it is controlled
by the boiler - being connected to the boiler's 'pump' terminals. This
allows the boiler to 'over-run' the pump after it stops firing in order to
carry away the residual heat.

My money is on a duff boiler PCB which is telling the pump to run long after
everything has cooled down. This could possibly be intermittent - so it may
happen on some occasions but not always.
--
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!

Central Heating Proble, pump running when all controls off, help please
 

wrote in message
...
On Jun 6, 1:04 pm, "Heliotrope Smith" wrote:
wrote in message

...



Background info:
Potterton Suprima 80 boiler 5 yr old
Honeywell Timer St6400
Honeywell 3 way valve V 4073A 1039
Pump Grunfos Selectric UPS 15-50
wired to Y plan
normal operation allows separate H/water from Heating or both together
all rads have thermostats

Problem:
Central Heating and water both switched off at timer yet yesterday
evening the pump was running and continued to run until we slightly
turn the white control anti-clock on the side of the Grunfos pump, the
pump then stops running.
Switch the Honeywell timer to hot water the boiler lights up but the
pump does NOT operate until we turn the white control back slightly
clockwise to the 90* setting mark on the pump.
So is this another 3 way valve issue or the pump not receiving the
correct signal ?

Any ideas or suggestion most welcome, some years ago we were able to
replace the 3 way valve after good advice from Roger Mills.

Happy to provide more info if required.
Steve

Could be a sticky 3 port. Switch off mains going to boiler and check the
manual arm on the valve head, if you can push it side to side with no
resistance then the valve is jammed. If however there is a strong
resistance
and the arm returns automatically when released then the valve is probably
ok.

The symptoms you describe suggest to me that the pump overrun is faulty
and
not switching off in which case a new control board would seem to be the
only cure.

The white control on the pump is in fact the pump speed selector and it is
not a good idea to switch off the pump by setting between speeds as this
would allow the boiler to fire up with no circulation and can cause damage
to the boiler.

Ok here 's the very latest _ the pump stayed back on after the mid day
hot water cycle had finished, so I took the cover off the 3 way valve
and found the earth wire was off inside the 4073A unit , re-attached
the earth wire switched off the circuit tested the value operation as
you suggested and found:
the 4073A 3 way valve lever was in the central position ie the middle,
when I pushed against it to the right there is resistance and then the
lever returned to the centre position [presumably on the return
springs inside the unit]
Does this suggest the valve itself is OK and its just the Honeywell
4073A unit with a malfunction ( this one has been on since 2005).
Hope this piece of info helps with the issue at hand.

PS thanks for the info on the pump itself the speed control seems to
be variable , we just turned it off last night.
I would not leave the cent heating on with the pump speed turned down/
off

Seems the 3 port is ok then.

The suprima will operate in pump overrun for a few minutes after burner shut
down. Give it at least 15 mins and if the pump is still running then check
for 230V on the SWL terminal on the boiler, you should not expect any
voltage if there is no call for heat from the controls.

If there is no voltage then it is the pump overrun playing up.

Central Heating Proble, pump running when all controls off, helpplease
 

On Jun 6, 6:00*pm, "Roger Mills" wrote:
In an earlier contribution to this discussion,



*wrote:
Background info:
Potterton *Suprima 80 boiler 5 yr old
Honeywell Timer St6400
Honeywell 3 way valve V 4073A 1039
Pump Grunfos Selectric UPS 15-50
wired to Y plan
normal operation allows separate H/water from Heating or both together
all rads have thermostats

Problem:
Central Heating and water both switched off at timer yet yesterday
evening the pump was running and continued to run until we slightly
turn the white control anti-clock on the side of the Grunfos pump, the
pump then stops running.
Switch the Honeywell timer to hot water the boiler lights up but the
pump does NOT operate until we turn the white control back slightly
clockwise to the 90* setting mark on the pump.
So is this another 3 way valve issue or the pump not receiving the
correct signal ?

Any ideas or suggestion most welcome, some years ago we were able to
replace the 3 way valve after good advice from Roger Mills.

Happy to provide more info if required.
Steve

This is unlikely to be a 3-way valve problem - otherwise the boiler would
fire in addition to the pump running.

You need to check how the pump is wired. Chances are that it is controlled
by the boiler - being connected to the boiler's 'pump' terminals. This
allows the boiler to 'over-run' the pump after it stops firing in order to
carry away the residual heat.

My money is on a duff boiler PCB which is telling the pump to run long after
everything has cooled down. This could possibly be intermittent - so it may
happen on some occasions but not always.
--
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,After undertaking some tests runs with the heat and hot water on
then off .
I just noticed the pump has stopped after about 20 mins as Heliotrope
Smith suggested and the 3 way valve lever is in Auto position with
resistance , so can I take it that this points to the PCB rather than
the 3 way valve, sorry about this latest update but just finshed our
tea and went to check - no noise from the pump !

Pse ignore my reply to you as 'an author' my fault

Central Heating Proble, pump running when all controls off, help please
 

Central Heating Proble, pump running when all controls off, help please
 

In an earlier contribution to this discussion,
The Medway Handyman wrote:


If the pump is running without a switched live, it has to be the pcb,
unless the pump hasn't been wired in correctly

.. . except during the 20 minute period after firing, when it's *supposed* to
over-run.

But, in this particular case, it sounds as if it's running for much longer
than this - so it's almost certainly the PCB.
--
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!

Central Heating Proble, pump running when all controls off, help please
 

In message , Roger Mills
writes
In an earlier contribution to this discussion,
The Medway Handyman wrote:


If the pump is running without a switched live, it has to be the pcb,
unless the pump hasn't been wired in correctly

. . except during the 20 minute period after firing, when it's *supposed* to
over-run.

But, in this particular case, it sounds as if it's running for much longer
than this - so it's almost certainly the PCB.


Yeah - I couldn't really contribute much, as I've not been able to post
most of the day

my website www.cetltd.com might be worth a read to the OP


--
geoff

Central Heating Proble, pump running when all controls off, helpplease
 

On Jun 7, 12:39*am, geoff wrote:
In message , Roger Mills
writes

In an earlier contribution to this discussion,
The Medway Handyman *wrote:

If the pump is running without a switched live, it has to be the pcb,
unless *the pump hasn't been wired in correctly

. . except during the 20 minute period after firing, when it's *supposed* to
over-run.

But, in this particular case, it sounds as if it's running for much longer
than this - so it's almost certainly the PCB.

Yeah - I couldn't really contribute much, as I've not been able to post
most of the day

my websitewww.cetltd.commight be worth a read to the OP

--
geoff

Many thanks to all those who replied , I plan to check the wiring
later today, will then update forum

Central Heating Proble, pump running when all controls off, helpplease
 

On Jun 7, 11:02*am, Mike wrote:
On Jun 7, 12:39*am, geoff wrote:



In message , Roger Mills
writes

In an earlier contribution to this discussion,
The Medway Handyman *wrote:

If the pump is running without a switched live, it has to be the pcb,
unless *the pump hasn't been wired in correctly

. . except during the 20 minute period after firing, when it's *supposed* to
over-run.

But, in this particular case, it sounds as if it's running for much longer
than this - so it's almost certainly the PCB.

Yeah - I couldn't really contribute much, as I've not been able to post
most of the day

my websitewww.cetltd.commightbe worth a read to the OP

--
geoff

Many thanks to all those who replied , I plan to check the wiring
later today, will then update forum

Right checked the wiring alll seems Ok , the only fault I found was
within the 3 way valve unit , the earth wire Gr had worked its way
lose and was off the contact screw.Retightened and now system runs
fine, but I plan to keep an eye on the PCB now its over 5yrs old.
So after nearly spending money I was able with this Groups help trace
the possible area for attention and resolve without laying out any
cash.

My thanks to all that replied , the power of the internet wins yet
again.