Ravenheat 820/20 pilot not lighting up

[Mikefromlondon]

A friend who lives locally asked me to help him re-light his boiler pilot went out and he tried to but failed as it would not relight.

this is what i found:

1. The pilot won't light despite I can hear the spark ticking and jumping across the elctrodes......so sounds like the gas may be turned off, so i checked all was available and all gas service valves were open.

2. There is a small round inspection window for flame viewing through which you see the flame, i opened the 3 screws and tried to light it manually whilst keeping the white starting knob pushed in.

3. as soon as I bring a lit match near the slot through which the lighted match is suppose to light the pilot, the flame gets drawn in as if there is a constant suction and so before the match can ignite the gas from the pilot, its gone off!

4. thought it might be a natural draft from the kitchen to the outside, so closed all kitchen windows and doors, and still this air being sucked in from this slot was phenomenol, and trying to light the pilot failed.

5. On reading the Manual, it states clearly that when lighting the pilot, the fan which is normally running at slow speed all the time, this fan running at slow speed is to stop accumulating any danagersous raw gas or other leathal fumes, good idea, but .....it creates so much turbulence that the pilot flame won't light up! The fact the manual then says that during ignition of the pilot, the fan cuts in at full speed, this makes it even worst.

6. So I am now wondering how do you light up the damn thind, as due to lot of turbulence it won't light the pilot....its like trying to light up a cigarette in a blowing wind! you can't light a lighter unelss you keep your hands around the lighter flame!

7. Finally, I played a trick and got my friend out of immediate trouble by lighting it with mains switched off at the boiler switch, this stops the fan from coming on, the turbulence stops, and the pilot lights up happily, and once the thermocouple has heated up, it holds the pilot in the on state, and as soon as I switched the mains back on, the pilot went out, that is because I hadn't yet replaced the glass window back on, and wanted to see if it will hold the flame, and as expeceted it didn't.

8. So I switched the mains off again, re-lighted the pilot with a match, and once it was held on through the thermocouple, I replaced the glass window and its seal, tightened the 3 screws, and then switched back the mains on, , the fan came on at slow speed, which you can barely hear, the flame continued to hold fine, but rather struggling to stay alive, due to the draft created by the fan running all the time at slow speed.

9.I am wondering what exactly may be the issue now, nothing had been changed on this boiler since last April when it was servied by a gas safe engineer, why all of a sudden has this trubulence started to effect the pilot flame? ,

10. The length of the pilot flame appears to be around what is indicated in the service manual...about 20mm long falling on the thrmocouple.

11. Due to turbulence, it is struggling a bit to remain lit, and it is sounding a little like a blow torch flame....you hear this high velocity sound of a flame, whyereas a pilot flame should be quiet and gentl, as in most older boilers is.

12. So since I relighted the boiler 3 days ago, it has gone off yet again once more.

13.It can only narrow it down to inadequate flame size, through restriction in the flow of pilot gas, perhaphs a blocked jet??

14.So what do you think, has anyone experienced this before, is it a regular issue with this boiler, my friend has had it serviced last year in april, and he said he has not had much problem with it in 10 years he had it, apart from a diverter valve that was replaced 2 years ago.

 

[45yearsagasman]

15. You don't know what you're doing. Call in someone who does.

 

[Gasop]

15. You don't know what you're doing. Call in someone who does.

16.

 

[Dan Robinson]

Speachless....

 

[Mikefromlondon]

15. You don't know what you're doing. Call in someone who does.

LOL! Not trying to be a smart ass, I was only trying to help an owner light up his boiler, using user instructions from the manual! when it refused, we both then pondered a bit further, tried to see why it wouldn't light up.

And it was he who suggested if we can light it up manually with a match.

Of course this will be looked into properly by a gas safe engineer, it might require a new gas control valve, or could simply be just requiring a clean up, but I don't go as far as that, as i am not registered, I only tried to help him light up, as his house was freezing cold,

I have worked on many gas boilers before it became a law and it became necessary to be registerd with Corgi, as this was not my field, I was into electronic control systems, I didn't persue with boiler repairs, but it does not make me any less competent.

Its like if a driver is banned from driving for say drink & driving, it does not make him loose his ability to drive a car.

And please don't make it look like all gas safe registered guys are highly competent, I have numerous examples and seen it and heard lots of stories where simple faults ended up costing their owners hundreds of pounds in repair cost, and in some cases perfectly repairable boilers were replaced because the corgi registered engineer could not fix it!

Another neighbour asked me to be present when a BG engineer was going to attend her premises, as her boiler would not often give her hot water, other times it would be just fine, so when the engineer called, she rang me and I went over, I pretended to be just a friend visting her, but essentially I was there with a purpose, to try and watch what this guy was going to do to fix the boiler, as she had a breakdown policy, the last time she called BG, they told her that her perfectly good condition boiler will need changing soon because it is more than 10 years old!

But a day before that, she had asked me for my general opinion as to what could it be this time when she doesn't always get hot water from the tap, I told her it could be several issues, including low water pressure, so I had a quick look under the front panel cover, and could see faulty part, just by looking at it, a pin from a diapgram differential switch was not striking the microswitch and was just short of tripping it.

And I was quite horrified when this gas safe engineer from BG, wrapped some PVC tape on the microswitch leaver so as to allow the striking pin from the differential DHW flow sensor to strike the microswitch just that little bit more, to enable it to snap in, I knew from my own experience that this would not solve the problem, I wouldn't even had tried it,

You would need to replace the diaphgram! as it was just not generating enough force due to a puncture or a leaky membrane, and not because it was short of tripping the switch in. So to overcome this short fall, he packed layers of PVC tape on the microswitch leaver, to make up just that extra margin.

When done, he tested it a few times, and being lucky, it just worked, but i knew he would be back soon! His mod was not going to work for long and I was surprised that it worked at all! he started to put covers back on, and finally asked her to sign the work sheet.

I told her discretely that he had not replace the faulty part and he will be back soon, and instructed her to go ahead sign his papers regardless.

I ws not going to embarrass him by chellenging him that what he did was illegal! As he was not suppose to know why I was there in the first place,

My purpose was to ensure that he was not going to fool her into beleiving that her boiler was beyond ecconomical repair and and to stop him condemning it, and persuade her to sign up a contarct from BG to supply a new boiler!

I had rest assured her that there was nothing major wrong with her boiler and all it needed is a new diaphgram in the DHW flow sensor.

Just as she was about to sign his papers, she asked him if she check it herself, and he replied yes its fine now, so she went over to the sink and opened the hot water tap, and sluckily for her, the boiler did not fire up for the hot water!

He looked upset! and murmurred something and said he would be back shortly, and went out to his van and got a brand new diaphgram switch assembly, complete assembly when all it needed was just a diapgram, and opened up the boiler covers to remov that faulty part replace it with the new one!

So my point is who do you trust, he was from a reputable company and should have known that you can't bodge things with a pvc tape! Luckily this lady had taken a contarct with BG for the past 10 years, and she calls them once every year and they service it regularly under this contract!

 

[Dan Robinson]

So you think you know more than those who designed and brought to market a boiler that has worked perfectly well with a permanently slow running fan?

You think that the fact that the fan runs the whole time, and has not been a problem for all those years, is now the cause of these problems? Of course the fxct that the pilot has problems now is a result of this fan. All those years have taken its toll on that poor pilot light.

Thought about it?

You are not as clever as you think; and BG is as far from a good example of engineering excellence as you can get - as a little search on here will demonstrate.

Another example of why Darwin needed to think harder.

 

[Mikefromlondon]

So you think you know more than those who designed and brought to market a boiler that has worked perfectly well with a permanently slow running fan?

You think that the fact that the fan runs the whole time, and has not been a problem for all those years, is now the cause of these problems? Of course the fxct that the pilot has problems now is a result of this fan. All those years have taken its toll on that poor pilot light.

Thought about it?

You are not as clever as you think; and BG is as far from a good example of engineering excellence as you can get - as a little search on here will demonstrate.

Another example of why Darwin needed to think harder.

Certainly not , this was my exact reason i gave to my friend that if it had been working like that for the past 10 years, why now should the fan turbulence be a problem, and adviced him to get someone to look at it properly, I can only light it up for him as a temprary measure, just so that he doesn't freeze! I just check the basics.

 

[swbjackson]

I expect the pilot is tired after working continuously for ten years. The poor thing just wants a rest.

Another thread proving why statutory registration of gas engineers was a good idea.