Central heating in need of some professional TLC

[mikemycrfot]

Hi to everyone.

My central heating system is an 8mm microbore system, over 17 years old,with 11 radiators attached. Quite recently I noticed that occasionally the heating does not come on when the temperature drops. The thermostat clicks in, the boiler clicks as though it is about to fire up, the pump is running, but the boiler does not light. I have looked around and asked a couple of people, (two heating engineers) and one of the engineers tolold me it is probably the solenoid valve on the gas line sticking. I managed to find a fault chart for my boiler make on line and after following the chart it seemed to indicate the same.
Just to be clear the pump runs, the fan does not, I can her a click as though the boiler is about to fire up but nothing happens.

It seems to happen more in the late afternoon or evening when the heating has been on quite a while. It has always come on as programmed in the morning.
I was concerned about the boiler so I got it serviced just before Xmas, and the boiler is OK. I asked the engineer who did the service, and he wasn't particularly helpful. He seemed to want me to tel him to replace the boiler. I kept asking him about the valve and he said it could be but if it is working there was not a lot he could do about it. He seemed to suggest if it failed he would be available for a callout but didn't want to do the work until then.

I don't want to wait for the boiler to fail completely before I get it sorted out, it doesn't make sense to me,is this unreasonable?

The second issue with the central heating is that I am pretty sure it needs a power flush. There is some sludge in the system, and on top of thet the pump has occasionally made the most horrendous noise for about a second, if I hear it (it has happened about twice in 4 months) I switch off the system and bleed some water out of the pump then restart the system and it seems to work OK

I think the system needs flushing out and some valves may need replacing on the radiators or even some of the rads. Does it need a new pump? If it does it does, I want the system working properly going forward, even though I am thinking of moving I dont want a bodge up doing.

The boiler is an Stelrad Ideal Classic NF 50
The pump is a Grundfos Selectric
The controller is a Potterton ep2001

If anyone can shed any light on the problem based on prior experience or recommend an engineer in the Leicester area (south west) I would be grateful

 

[REDSAW]

welcome to the forum.

best thing to do is call gas plumber out in the morning when it dosnt work.

 

[mikemycrfot]

yes like most of thesethings catching it when it is actually faulty is the most difficult thing. it wen off this morning and then when the missus got up and decided she was cold, she clicked it on and off and hey presto it sprang into life,

 

[Puddle]

The classic is a good boiler,could be solinod on gas valve,you would have to check if power there when not working,could be boiler thrmostat with bad contacts, also could be heating motorised valve sticking when opening not opening fully onto micro switch
With pump could be that incorrectly positioned and collects air sometimes if head pointing upwards

 

[mikemycrfot]

thanks ive got an engineer coming out Saturday to give a quote for powerflushing, he will have a look at it then and see if he can shed some light on it. Nice to know the boiler is a good one, when I got it serviced just before Xmas the burner head (if that the right term?) was in very good nick, so that's good I guess.