Boiler turning off 2 hours after Central heating timer comes on. Only fires up again with...

[Tom Parkin]

Afternoon!

I seem to have an issue with my central heating staying on.

As its winter, we have it set on a timer. The first couple of cold days it worked fine with no problems. (on in the morning for a few hours / then again in the evening from 6pm until around 10pm).

The last couple of mornings and nights its not come on as usual with the timer. Worth noting that the timer is still powered up (all lights are on) but the boiler is not on. Instead I then have to manually restart the boiler. As soon as I do that the CH system fires up and starts working.

NB - circulting pump has power and works whilst boiler is on. When boiler turns off the pump remains on but stops pumping (I imagine this is normal?).

However, within a couple hours it turns itself off again. (I don't beleive its the thermostat cutting in as the temp in the house drops right down and still the CH doesn't fire up again).

I've recently done some plumbing work in the bathroom so have drained the system a couple of times. Since refilling, all the rads have been bled including the bleed off pump / circulating pump in the cylinder cupboard.

I am trying to work out if its one of the following (or none of them!)

- Knackered Boiler.
- Knackered Thermostat.
- Knackered Timer.
- Air in the system.
- Knackered Circluating pump.

Boiler age - 5 years
Thermostat - fairly old honeywell system, positioned by the lounge.
Timer - probably from the 90's.

Has anyone experienced similar symptoms? If so what else can I try before I start buying new parts?

Many Thanks
Tom

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[SimonG]

Time to get the multi meter out and tracing where the controls are losing the live.

 

[Tom Parkin]

Time to get the multi meter out and tracing where the controls are losing the live.

Hey Simon, thanks for the reply.

As far as I can see everything is still recieving power. Circulating pump lights are on. Timer unit lights are on. The only thing that stops working is the boiler. I assume that still has power going to it because I push the restart button and it fires back up.

Am I missing something?

Thansk again

 

[SimonG]

Sounds like the actual boiler then. Need a gas safe engineer.

 

[Tom Parkin]

Sounds like the actual boiler then. Need a gas safe engineer.

OK.

So could it be that the boiler is being starved of gas and cutting out?

 

[C Thompson]

I am having similar problems but I just signed up and do not see any kind of a button or link to click so that I can post a new thread about it.

 

[Tom Parkin]

I am having similar problems but I just signed up and do not see any kind of a button or link to click so that I can post a new thread about it.

I seem to have fixed it! I drained and bled the system, bleed value in the cylinder cupboard and circulation pump again. Its been 2 days now and it seems to be working ok!

It seems that air in the system was the main cause of my problems.