Potterton Boiler staying on

[sophie]

Hi, hope someone can help. I have a potterton boiler and when I came home the other day the boiler was running and the house was very hot! There is a timer on the wall and it appears that this was being ignored as none of the lights were on the timer. I switched the boiler off completely, left it for a bit and then switched it back on and all was fine. However, the same thing has happened again today, I have come in and the heating was still on even though it should have gone off. Again I have switched the boiler off and then back on and it has not yet come on (which it shouldn't as the timer is set for it to come back on this afternoon!)

My husband has mentioned it could be a three way valve thingy in the airing cupboard but could it be an issue with the timer?

Any thoughts would be very welcome!
Thanks
Sophie

 

[PlumbBobBob]

it is possible that the three way valve actuator has stuck open. there is a micro switch which has to make for the boiler and pump to come on which may be getting stuck. i would get someone in to have a look to find out what is happening.

 

[Puddle]

What model of boiler is it,how are you turning boiler off ?

 

[sophie]

hi it is a potterton suprima 40.

it does not seem to be the pcb as im not getting lock out this is what is happening.

boiler comes on for 20 mins @ 6.10 am for hot water then off at 6.30 then
boiler comes on for 1hr @ 6.50am for heating and off @ 7.50 am then

i had to come back after school run as forgot something at around 9.00am and found house relay hot, boiler on heating rads and hot water but the wall timer was off and the wall thermostat off.

I switch the hole lot off at the mains switch then back on again 10 seconds later and has been ok all day.

This has happened 3 time over a 3 week period now and every time it does the some: boiler on, timer off, wall thermostat off, hot water very hot and all rads very hot as well as the house.

the 3 way valve is 10-11 years old but seams to be working all ok hot water when asked for and heating when asked for and the valve moves back and forward.

Any ideas

Sophie & Pat

 

[sophie]

potterton suprima 40

 

[GrahamM]

Chances are it is the actuator valve that is either starting to seize up and keep the switch on or it is the switch on the valve itself that is faulty. As steve mentioned unless you are very handy with plumbing/electrics you should have someone look at it.

 

[sophie]

Hi all

Thanks for your help

my husband has taken the cover off the 3 port valve and lubricated all moving parts and the micro switch and all be ok for 4 days now.

Will keep you posted

Sophie