No heating?

Dedekind

Hello

We woke up today with a weird situation in our central heating. We left it running overnight last night as we usually do. The radiators upstairs were lukewarm, downstairs they were simply cold.

Some background on house:
- gravity fed system, boiler is old but functioning. There is no pressure gauge or anything to look at other than a thermostat going from min to max. It's a Potterton Netaheat Profile. It was ON this morning and didn't seem to be faulty.
- upstairs has new plumbing and new radiators since the summer
- downstairs still has old piping and old radiators
- both new and old rads were working fine. I bled them a couple of months ago.
- the only thing that changed since yesterday is that last night I put the boiler thermostat at "2", previously it was at "1".
- the pump in the airing cupboard was very fast a few months ago, I changed the settings to a lower value about 2 months ago. Today it was quite low.
- hot water: it's hard to say if it works or not. In the morning today there was enough to wash up, take a shower and etc but I don't know if it's from previously heated water that stayed hot in the cylinder..
- system will be completely changed in a few months for unvented cylinder or combi boiler, but for the time being I want to be heated..


Anything I can do before a call out? It's freezing this week outside. I am zero DIY when it comes to plumbing/boilers. There is a cold water tank in the loft, I have never been up there myself though and I don't feel like to unless absolutely necessary (other people have gone though, including surveyor, a plumber a few months ago to clean the tank, and maybe a couple more builders have took a look for some other reasons so I'm not concerned about the loft itself at the moment..).

I have BG home care with a £99 excess which I don't find overly expensive if they fix the problem. But they don't have appointments for a few days and as I said it's kind of freezing weather these days..

Paula_Smith

As you changed the boiler thermostat setting yesterday I would suggest putting it back as it was.

And bleed the radiators for good measure.

FreeBear

Can you hear the boiler fire up when the heating comes on ?

It could be the wall mounted timer/control has died on you - Any sign of life in it ?

Also worth checking the fuse - There should be a fused switch near to the boiler or timer/control. Check the fuse, and if it is blown replace with one of the same rating (should be something like a 3A fuse). If the heating still doesn't work, time to call in an engineer.

Dedekind

Before leaving today I put it back on 1.. and now it's working fine.

Maybe the boiler thermostat is faulty and only works properly in 1?

nofoollikeold

Could be:
Flow restriction in the system somewhere (sludge, weak pump, sticking valve etc.).
With boiler on heat 1, system has enough time to get rid of heat.
Boiler on 2 = system can't get rid of heat, boiler overheat thermostat turns it off.

Dedekind

Hmm ok thanks! Given it will be changed in a few months I'll just leave it at 1 which is enough to keep the house warm even in this weather. It doesn't get much colder than this over here.

Out of curiosity will a power flush, when installing new boiler, get rid of any potential sludge?