Potterton Prima F40 issues

[gunnag]

I have a Potterton Prima F40 boiler which is approx 16 years old. The boiler supplies heat for conventional hot water via a tank and central heating via radiators.
Recently I have noticed an issue whereby the boiler attempts to start but fails to light the main burner. Eventually after several attempts the boiler will light and run for several minutes before stopping.
The sequence of events seems to be as follows:-
- a call for heat is made via the room/cylinder thermostat
- the pilot light is lit via spark
- the fan starts up
- the pilot light and fan continue to run but the main burner doesn't light, this can continue for a minute or two until the sequence stops
- eventually, after multiple attempts, the main burner lights and runs for a few minutes before stopping again.

The pilot light and fan seem to work OK so what else could cause this behavior?

Obviously IM not going to fix this myself but thought it would be useful to have some ideas as to what may be wrong so I can point a gas engineer in the right direction.

All info welcome.

 

[Agile]

Obviously IM not going to fix this myself but thought it would be useful to have some ideas as to what may be wrong so I can point a gas engineer in the right direction.

All info welcome.

Do you really think that we will believe you?

You have already opened a combustion chamber and replaced a fan! Don't you remember this:-

The original problem was that the boiler fan was broken (error F8), I managed to buy a new fan and fit it myself, the boiler now works great.

As for "wanting to tell the engineer what is wrong" do you really think any engineer is not going to be able to diagnose the fault themselves?

It seems to be pretty obvious to me that you just want to know what is wrong so that you can fix it yourself again!

Its a gas/combustion issue which we don't advise on here!

The only advice is to call a competent engineer as you pretended you were going to do!

Tony

 

[gunnag]

Do you really think that we will believe you?

Read more: //www.diynot.com/forums/plumbing/potterton-prima-f40-issues.382818/#2934811#ixzz2kHKMbxSj

Do you really think I care what you think? I was simply asking for some advise as to what may be wrong.

You have already opened a combustion chamber and replaced a fan! Don't you remember this:-

That was a completely different boiler in my partners house not the boiler IM talking about now.

Its a gas/combustion issue which we don't advise on here!

How do you know this, you haven't seen my boiler. It could well be a PCB, sensor or other electrical issue.

The only advice is to call a competent engineer as you pretended you were going to do!

This is typical of the arrogant self interested opinion of so called 'Gas Engineers' who then come around and want to fit a complete new boiler for thousands of pounds when all that is wrong is the simplest of components has failed and needs changing.

I cant see why anyone fixing boilers should proclaim to be a 'Gas Engineer', a better term would be a gas fitter, in other words someone who comes around, performs some elementary checks and changes some components based on gas safety standards.

So Mr Agile, do you have any constructive comments as to what may be at fault with my boiler?

 

[misterdubya]

I can tell you whats at fault / is wrong. It's this...

the pilot light and fan continue to run but the main burner doesn't light, this can continue for a minute or two until the sequence stops
- eventually, after multiple attempts, the main burner lights and runs for a few minutes before stopping again.

As for telling you how to fix it.... you didn't ask.

Get it diagnosed by an RGI. This sounds like a very simple fault on what is a very good boiler - as long as it's looked after.

Tony is following forum rules, I assume you read them?

 

[45yearsagasman]

All that needs to be said on every post involving gas repairs is:- "No DIY advice is given as per forum rules". Instead of this people get abusive and in many cases rude replies. This happens on a large number of posts, but I guess some think it is their remit to do this. You know who you are.
Rant over for now.