Potterton E2000 cant turn off the Central Heating

[shinares]

Hi,

I have a problem with my Potterton E2000 timer. 2 weeks ago I noticed the timer was off so I turned off its main power and then turned it back on and the timer is now on. However, now the central heating is "always on" regardless the setting on the timer. The hot water control from the timer however is still working accordingly.

I've tried to changed the battery of the timer but it still unable to control the central heating (it is still 'always on'). At the moment I just manually turn off the boiler (Baxi Bermuda LFE 3) until I get the solution for this problem.

Any suggestion please ? Thanks.

 

[45yearsagasman]

It may be the programmer, but it could also be a faulty motorised valve that you may have, and have failed to mention in the description of your system.

 

[shinares]

Hi 45yearsagasman,

Thank you for the reply. Here are the pics

The potterton

The thermostat

The hot water tank :

If I understand correctly, this is the zone valve (the box behind the pipe) ?

a switch which attached near the valve with three numbers on it:

This morning I tried to turn the thermostat on the wall to the lowest but the central heating still on and getting hotter and hotter. And still I cant turn the central heating on and off through the potterton.

Any suggestion please ? Thank you.

 

[D_Hailsham]

The box behind the pipe in pic 3 is a motorized valve. You only mention one valve, so it will be a mid-position type, not a zone type.

There is a lever in the slot which is just visible in the pic. Try moving the lever to the right. Is is loose, or does it need some effort to move and then go back to the left when you release it?

If the lever is loose, turn off the main power to the system and try again.

What happens to the lever this time?

Does the cover for the motorized valve have a small bump on the top at one end?

PS the thermostat on the side of the cylinder is set too high; reduce it to 60.

 

[shinares]

Hi D_Hailsham,

Thanks for the detail explanation.

There is a lever in the slot which is just visible in the pic. Try moving the lever to the right. Is is loose, or does it need some effort to move and then go back to the left when you release it?

The lever is loose, no effort needed to move it and did not go back to the left when i released it. I've tried both when the heater is on and the heater is turned off manually from the thermostat on the boiler.

Does the cover for the motorized valve have a small bump on the top at one end?

yes it does have a small bump on the top of the one end

If the lever is loose, turn off the main power to the system and try again.

What happens to the lever this time?

Before I do this, what are the possible scenarios in relation on what may actually broke ?


thanks[/quote]

 

[shinares]

Can I just show you the picture of the whole system ?

Untitled

• shinares
• 7 May 2013
• 1

 

[45yearsagasman]

You have 2x 2 port valves and it is most likely that one of the valve end switches is staying closed or one of the valves is seized.
They look a bit of a pain to get to.

 

[D_Hailsham]

Untitled

• shinares
• 7 May 2013
• 1

Is that the same valve as in the earlier pic or a second valve?

The fact that the lever was loose means one of two things: (1) the valve is being held open; or (2) the valve is stuck open.

Turning off the power (setting programmer to off is not sufficient) will mean that the valve is no longer held open and you should then have resistance to movement. So, if the lever is still loose the valve must be stuck open.

The bump on the top of the cover means that the actuator (that's the complete box) can be separated from the pipe part of the valve. (One screw to remove cover, two screws to separate). This would then expose the valve spindle, which should turn easily by hand - less than a quarter rotation). If it is stiff a little silicon lubricant should help (NOT W40, which will rot the seals).

 

[shinares]

Hi D_Hailsham,

Thank you for the suggestion. I have managed to remove the side of the cupboard and yes both valves are the same. I tried to turn on the water heater from the programmer and I can hear the mechanical movement on one of the valves (the brass-colored one on the right). The same cant be heard when I turn the central heating on from the programmer.

I just turned off the power and I found there is still no resistance from the lever (its still very loose). Do I still need to proceed to

(One screw to remove cover, two screws to separate). This would then expose the valve spindle, which should turn easily by hand - less than a quarter rotation). If it is stiff a little silicon lubricant should help (NOT W40, which will rot the seals).

or is this actuator need to be replaced ?


thank you

 

[D_Hailsham]

I have managed to remove the side of the cupboard and yes both valves are the same.

Thanks for answering my question, even if it was in a roundabout way.

I just turned off the power and I found there is still no resistance from the lever (its still very loose). Do I still need to proceed to

(One screw to remove cover, two screws to separate). This would then expose the valve spindle, which should turn easily by hand - less than a quarter rotation). If it is stiff a little silicon lubricant should help (NOT W40, which will rot the seals).

Yes. The lever is still loose when the power is off, so the valve is stuck open. Removing the actuator will allow you to check if the spindle turns easily and lubricate if necessary.

is this actuator need to be replaced ?

The sticking spindle is in the other part of the valve, so replacing the actuator will not solve that problem. If lubrication does not help you will have to change the complete valve - that's a drain-down job.

It might be a good idea to check the other valve.

 

[ianmcd]

could just be that the synchron motor has seized