Boiler won't fire! Any ideas?

Boiler won't fire! Any ideas?

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R1 Indy

Original Poster:

4,382 posts

183 months

Wednesday 22nd October 2014
quotequote all
Turned the central heating on for first time since last winter the other day, but it appears the boiler will not fire up!

It starts for about 10-20 secs then shuts down, if I press the re-set it does the same straight away.

There is defiantly oil in the tank, and can see oil in the clear tube in the boiler,

The lock off light illuminates, I guess this means some sort of safety shutdown?


Anyone any ideas, as could do with some heating on!

Can't find a heating engineer able to come out any time soon.

It's a Worcester danesmoor 20/25 made in 1997.

Cheers

ooo000ooo

2,530 posts

194 months

Wednesday 22nd October 2014
quotequote all
Our gas boiler did something similar first few times we put the central heating on last week although it ran for about 10 minutes each time. Worked ok ever since, is there some kinda of sensor that gets gummed up with it not being used for so long but cleans up as the central heating water circulates?

crankedup

25,764 posts

243 months

Wednesday 22nd October 2014
quotequote all
Thermo sensor gone west or needs clean up maybe. Do you still have the boiler handbook, it may well show the whereabouts of the sensor.


Rickyy

6,618 posts

219 months

Wednesday 22nd October 2014
quotequote all
Does it sound like it ignites before it shuts down? If so, it points to a faulty/dirty photocell.

If it's dirty, a quick clean wipe will solve it, but does suggest a combustion fault and that a service may be needed.

If it's failing to ignite altogether, it could be a few different issues.

Spice_Weasel

2,286 posts

253 months

Wednesday 22nd October 2014
quotequote all
R1 Indy said:
Turned the central heating on for first time since last winter the other day, but it appears the boiler will not fire up!

It starts for about 10-20 secs then shuts down, if I press the re-set it does the same straight away.

There is defiantly oil in the tank, and can see oil in the clear tube in the boiler,

The lock off light illuminates, I guess this means some sort of safety shutdown?


Anyone any ideas, as could do with some heating on!

Can't find a heating engineer able to come out any time soon.

It's a Worcester danesmoor 20/25 made in 1997.

Cheers
I was about to start a thread on exactly the same topic. Mine is a Danesmoor 26/32 displaying similar problems. It won't come on via the timer in the morning. I reset the amber light and it fires, runs for 10 minutes or so then stops until I press the reset button again.

Rickyy

6,618 posts

219 months

Wednesday 22nd October 2014
quotequote all
Spice_Weasel said:
I was about to start a thread on exactly the same topic. Mine is a Danesmoor 26/32 displaying similar problems. It won't come on. Is the timer in the morning. I reset the amber light and it fires, runs for 10 minutes or so then stops until I press the reset button again.
Running for 10-20 minutes points towards the solenoid on the oil pump. They work ok when cold, but fail when it warms up. £20-£30 for the part and takes seconds to fit.

Spice_Weasel

2,286 posts

253 months

Wednesday 22nd October 2014
quotequote all
Thanks very much

R1 Indy

Original Poster:

4,382 posts

183 months

Wednesday 22nd October 2014
quotequote all
Rickyy said:
Does it sound like it ignites before it shuts down? If so, it points to a faulty/dirty photocell.

If it's dirty, a quick clean wipe will solve it, but does suggest a combustion fault and that a service may be needed.

If it's failing to ignite altogether, it could be a few different issues.
It sounds to me like it's igniting, it whirles away for around 10-20 secs before cutting out.

Is the photocell the little black sensor, next to the cutout sensor?

R1 Indy

Original Poster:

4,382 posts

183 months

Wednesday 22nd October 2014
quotequote all
Just googled photocell, I take it it's the black stick that just pushes in?

If so, it's clean as, I just tried starting without the photocell, and did exactly the same.

Could it be a faulty photocell?

Rickyy

6,618 posts

219 months

Wednesday 22nd October 2014
quotequote all
R1 Indy said:
Rickyy said:
Does it sound like it ignites before it shuts down? If so, it points to a faulty/dirty photocell.

If it's dirty, a quick clean wipe will solve it, but does suggest a combustion fault and that a service may be needed.

If it's failing to ignite altogether, it could be a few different issues.
It sounds to me like it's igniting, it whirles away for around 10-20 secs before cutting out.

Is the photocell the little black sensor, next to the cutout sensor?
Usually a long black probe that points into the burner, should just pull out.

Rickyy

6,618 posts

219 months

Wednesday 22nd October 2014
quotequote all
R1 Indy said:
Just googled photocell, I take it it's the black stick that just pushes in?

If so, it's clean as, I just tried starting without the photocell, and did exactly the same.

Could it be a faulty photocell?
Possibly. With the photocell out, can you see a flame through the hole?

R1 Indy

Original Poster:

4,382 posts

183 months

Wednesday 22nd October 2014
quotequote all
Rickyy said:
Possibly. With the photocell out, can you see a flame through the hole?
Just checked, no flames, does this mean it's not igniting?

Rickyy

6,618 posts

219 months

Wednesday 22nd October 2014
quotequote all
Possibly, you should see a big orange flame.

If it's not getting to the ignition stage, it could be a fuel delivery issue or a spark issue.

You can test the solenoid by removing it from the pump, placing something magnetic in the middle of it and you should feel it attract the object as the burner goes through the motions.

Also check that no oil valves (including fire valves) have been closed.

BertyFish

618 posts

164 months

Wednesday 22nd October 2014
quotequote all
I might be completely stupid but could it be a a burnt out thermocouple?

Had to replace 2 in 5 years now...

Rickyy

6,618 posts

219 months

Wednesday 22nd October 2014
quotequote all
Oil boilers don't have thermocouples. The photocell performs a similar task.

BertyFish

618 posts

164 months

Wednesday 22nd October 2014
quotequote all
Oops sorry I was being stupid then, sounded similar.

Its always when it starts to get bloody cold....

Luckily my old boiler although rubbish is a bolt off / on job so I can even do it myself.

Sorry I couldn't help with this.

BertyFish

618 posts

164 months

Wednesday 22nd October 2014
quotequote all
Oops sorry I was being stupid then, sounded similar.

Its always when it starts to get bloody cold....

Luckily my old boiler although rubbish is a bolt off / on job so I can even do it myself.

Sorry I couldn't help with this.

Converse2020

325 posts

121 months

Thursday 23rd October 2014
quotequote all
Try the transformer ...cheap and cured my symptoms which sounded identical to yours. I tried photocell / thermocouple / clean / oil filter etc - none made any difference.

Oil manufacturer helpline said sounds like transformer - that's what I'd try first off. It was. Part was around £20 (not paid oil chap yet)

Sorry - can't recall my oil boiler make but it's a free standing job about 8 years old sat in garage !


R1 Indy

Original Poster:

4,382 posts

183 months

Thursday 23rd October 2014
quotequote all
Cheers, i will have a look at this tonight.

a bit of googling tells me i can test this by arcing a screwdriver between the terminals? (obviously a proper insulated one)

crankedup

25,764 posts

243 months

Thursday 23rd October 2014
quotequote all
Rickyy said:
Oil boilers don't have thermocouples. The photocell performs a similar task.
Sorry OP, I also made this mistake using wrong name of component.