Boiler keeps firing up with no demand

kwame41

I had trouble with my Vaillant Combi boiler doing a similar thing with the heating.


Turns out the wi-fi room stat was faulty got that replaced and it solved the problem.


Just a thought if you have a wireless one as well.

ninjaef

No, its a room stat - just one - and noi TRVs on the rads, although I will be connecting WiFi TRVs in due course once I get this heating problem sorted. Got my multimeter now so will test a few circuits and outputs when I get home.

kwame41 wrote: »

I had trouble with my Vaillant Combi boiler doing a similar thing with the heating.


Turns out the wi-fi room stat was faulty got that replaced and it solved the problem.


Just a thought if you have a wireless one as well.

southcoastrgi

ninjaef wrote: »

Hence why I am here, to obtain help, if I were a Gas Safe engineer I doubt I would be asking this question on MSE would I ?

I didn't say you would mess about with the boiler did I, plus just because you are a Gas Safe Engineer doesn't mean you can repair heating systems

ninjaef

Sorry, I misunderstood you then. Apols. BTW, I am *not* a Gas Safe engineer.

southcoastrgi wrote: »

I didn't say you would mess about with the boiler did I, plus just because you are a Gas Safe Engineer doesn't mean you can repair heating systems

ninjaef

Ok folks, problem sorted. Took me a while to find it, but the digital CH Room Stat (there's only 1) was sending erroneous but intermittent "ON" demand for CH. In concert with this, the CH Zone Valve armeture was intermittently sticking and forcing the "OPEN" state. So combined with Zone valve sticking open and intermitten demand for CH , the boiler was firing up regularly for 2 or 3 minutes.

I replaced the Zone valve and Room Stat - both procured from eBay - with quality Drayton trade recommended units from ScrewFix and no problems now. No wonder my gas bill wasnt changing much through summertime , grrr.

Well done a&akay and Alex1983 who correctly proposed the sticking zone valve.

Mytholm

My Glowworm Micron boiler fires up even when the programmer is switched to OFF and the heating thermostat is turned down low. There is a one year old Drayton zone valve actuator in the airing cupboard by the tank, so this should not be the problem. The water gets very hot so I have to switch off the electric supply to the programmer. My plumber does not know what the problem is, does anyone have any ideas?

Homer_home

For starters start your own post it is not good to hijack someone else's thread

Mytholm

Rather a rude comment.  All I am trying to do is sort out my problem and I posted the details on a site where people had similar problems.  It seemed a logical thing to do!

cajef

Mytholm said:

Rather a rude comment.  All I am trying to do is sort out my problem and I posted the details on a site where people had similar problems.  It seemed a logical thing to do!

Not rude at all it is considered bad manners to hijack someone else's thread, plus if you start your own you are more likely to get more advice.