No CH - Boiler Not Attempting To Fire Up

[tigers999]

Hiya all,

I have an Ideal ICOS condensing boiler (HE12 I think) and I have no Central Heating today

The boiler is sat in 0 mode but when I request heating via the thermostat the boiler doesnt click on or even look like it has been asked to do anything. Any ideas please?

When I press reset it flashes H and then b but when I turn it on and off again it just says 0.

Thanks in advance for any help

E2A - I looked up the code in the destructions but there isnt such a code. Just something about HR.......and checking thermostat valves fitted!

 

[Agile]

I think you have a heat only boiler.

It sounds like there is no demand for heat. You can check for the relevant voltge being applied ( not ) to the boiler.

It may be a motor valve fault.

Tony

 

[tigers999]

Hiya,

Thanks for the reply....tbh I wouldnt like to say hand on heart lol

Although I do suspect it could be both hot water and heat because it was on earlier.........I suspect heating up the hot water cylinder upstairs, rather than the central heating as the radiators didnt come on.

So the boiler is definitely lighting but it just doesnt kick in when I turn the thermostat up past the "click"...........I am guessing this could be one of a few problems and I should get the boiler man out? I rang him today but no call back (

 

[Armo74]

Sounds like the motor in your valve isn't moving the valve into position. so not connecting with the microswitch to fire the boiler up.

 

[tigers999]

Thanks for the replies, really appreciated.

Its strange because I have just ran a bath and just as I sat in it I heard the boiler fire up! I guess this was to heat the hot water for the bath. I have now come downstairs and the radiators are on!

Looking back, the same thing must have happened lastnight after my wifes bath. The boiler came on to heat the water but also warmed the radiators up. Eventually though the radiators clearly cool down and when the boiler should refire to keep them hot, it doesnt.

Is this any more helpful? I will ofcourse ring the boiler man again but its weird because teh heating and boiler does work clearly. It just doesnt click on via the thermostat like it should.....is this the fault you mentioned maybe Armo74 mate?

Thanks again

 

[warmadmax]

Sounds like the motor in your valve isn't moving the valve into position. so not connecting with the microswitch to fire the boiler up.

i'd say Armo74 was on the right track.
based on what your saying, it sounds more like the microswitch is faulty in the CH zone valve.

Turn thermostat up to max and try the lever on the zone valve and see if the boiler fires, if it doesn't then the switch is at fault, if it does then it's not opening fully (as per Armo74).

 

[tigers999]

Sounds like the motor in your valve isn't moving the valve into position. so not connecting with the microswitch to fire the boiler up.

i'd say Armo74 was on the right track.
based on what your saying, it sounds more like the microswitch is faulty in the CH zone valve.

Turn thermostat up to max and try the lever on the zone valve and see if the boiler fires, if it doesn't then the switch is at fault, if it does then it's not opening fully (as per Armo74).

Thanks again for the reply.....I hate to say it, and I am sure you get it all the time but............its working again properly today

I guess I should turn the thermostat right down and wait for the house to cool and fire it back up and see what happens......big risk when we have heating lol

 

[tigers999]

Sounds like the motor in your valve isn't moving the valve into position. so not connecting with the microswitch to fire the boiler up.

i'd say Armo74 was on the right track.
based on what your saying, it sounds more like the microswitch is faulty in the CH zone valve.

Turn thermostat up to max and try the lever on the zone valve and see if the boiler fires, if it doesn't then the switch is at fault, if it does then it's not opening fully (as per Armo74).

Back again lol

The central heating has stopped working again so clearly something has an intermitent fault. When I ran a bath just then the boiler fired up afterwards to re-heat the water so I know the boiler is actually working and lit....it just doesnt fire the boiler up for heating when I turn the thermostat!

The zone valve lever....it is currently at the left hand side of the zone valve looking at it....should I move this to the right and see if the boiler fires up for heating?

Thanks again all. I have rang a boiler man but he cant get out until Monday so just looking for a temporary fix

 

[Armo74]

You could move the valve over with the manual lever and that will put it into mid-position which will give you heating aswell and click it into position so the spring doesn't return it back to hot water only. Then you need to turn your boiler thermostat down a little and your cylinder stat up a little and set the programmer to hot water only this will ensure that the cylinder stat never reaches temperature and will give you heating. Please be aware this is only a temporary fix to give you heating until you get it fixed.

 

[tigers999]

Thanks Armo74, really appreciated

I am guessing by what you have said, the lever on the zone valve should move back to the left when I have moved it over to the right? As though it is on a spring? If so, mine doesnt. It is almost loose if that makes sense.

Thanks again mate, really appreciated. Its not a big problem without heating because we can wrap up for a few days....its just strange how it started working again lol

 

[Armo74]

In that case then if the lever is floppy and being as it is an intermittent fault it maybe that the valve is occasionally getting stuck and then working it's way free when whatever is making it stick has been dislodged. Or it maybe a sign that the valve body is slowly on it's way out Also your are correct in saying that the valve moves back into hot water only position via a spring return.

 

[tigers999]

eeek I give up lol

I just ran my wife a bath and the boiler again fired up to warm the water again as before. This time though it has "kickstarted" the heating again and the radiators are coming back on?

Any ideas? Could the zone valve cause this intermitent fault?

I will add aswell for what its worth, I put the lever on the zone valve in the middle while I ran the bath.

Thanks again...I just have a feeling that the boiler man will come and it will all be working!! Sods law type of thing! Or is it a definite fault that he will probably spot?

 

[tigers999]

In that case then if the lever is floppy and being as it is an intermittent fault it maybe that the valve is occasionally getting stuck and then working it's way free when whatever is making it stick has been dislodged. Or it maybe a sign that the valve body is slowly on it's way out Also your are correct in saying that the valve moves back into hot water only position via a spring return.

Sorry mate, I think we were typing at the same time!

Ahhhh that would make sense then. Maybe me moving the lever to the middle has kicked the heating in just now as the boiler had fired up for the hot water?

Probably on its way out anyway if it is supposed to spring back slowly because it doesnt lol

Thanks again mate...I guess I should mention all of this to the boiler man?

 

[Armo74]

I would say that it is probably a faulty microswitch then. possible replacement actuator.

 

[tigers999]

Hmm I am sure thats what he fixed last time...wonder if its gone again!

Anyway, brilliant mate. Thanks again for your help! I will let you know what he says next week, atleast weve got some heating until then