Gas Boiler: Gas build up before ignition

[ActiveValue]

Hi,

I have a Potterton Kingfisher 2 boiler. This morning it has started behaving strangely, the boiler appears to be letting a significant amount of gas build up before then igniting the gas. This has the consequence of causing what sounds like a big "whoooomf", which scares the cat who likes to sleep near the boiler in its warmth.

I've checked and the pilot light is fine and so it doesn't particulary worry me but it's obviously not performing to spec and I wondered if this is something that I can fix or do I need to get somebody out to look at it?



The system as a whole is functioning OK, we've always had a minor issue with it that I presume is unrelated but I'll describe in case it isn't. We have a twin valve system that permits the CH and HW to be heated independently, most of the time it's set for the CH and HW to both come on in the morning and the evening. However, in the winter the CH is set to come on during the day as well, just on its own. When the CH is set to come on on its own then the whole system doesn't perform as well:

The boiler switches on to heat water but then switches off after about 5 minutes even though the CH room stat hasn't reached the required temperature. I can still hear the pump pumping whilst the boiler isn't heating and then about five minutes later the boiler will switch on again. However, a reasonable room temperature is maintained and we've generally accepted this because ... it is noticeable that if the HW is switched on during the day in the winter then the above problem doesn't occur, hence if the house is particularly cold during the day in the winter then we manually flick the switch on the timer for HW.

Any help appreciation, thanks.

 

[Rob]

When was it last serviced?

Is this a room sealed (metal box outside) of open flue (one big pipe off the top)

rob

 

[ActiveValue]

It was last serviced in March 2006 and is serviced about the same time every year.

The boiler is in our utility room, the flue feeds into an old-fashined brick chimney via "one big pipe off the top". Air is vented into the room via (a) a vent in the corner of the room, and (b) the glass over the top of the door was replaced a while ago with a wooden grill to permit further air to enter.

 

[Rob]

Get it serviced again including flue performance check and spillage check.

Compartment ventilation should be suitable air grills high and low level not louvre doors.

rob

 

[Agile]

Is this a proper service when the burner assembly is withdrawn and cleaned ?

Or is it a British Gas "service" which is only a safety check?

Tony

 

[ActiveValue]

It's a "British Gas Service". I take it that you're suggesting it should be serviced by somebody else?

 

[kevplumb]

no he is suggesting it gets done properly

 

[ollski]

Is this a proper service when the burner assembly is withdrawn and cleaned ?

Or is it a British Gas "service" which is only a safety check?

Tony

Its not on an open flue Tony it is a full service every time...allowing for the variation in indivudual engineers of course as with everyone.

 

[corgiman]

Is this a proper service when the burner assembly is withdrawn and cleaned ?

Or is it a British Gas "service" which is only a safety check?

Tony

Its not on an open flue Tony it is a full service every time...allowing for the variation in indivudual engineers of course as with everyone.

sorry to disagree oll but thats ******

they just stick the FGA probe up the draft diverter, if the reading is below .004 they do nowt

they do do spillage and FF if your lucky but FULL service dont make me laugh

Believe me THATS how they told me to carry out a service on an Ideal Mexico when I sub for them, it was at this precise moment I told em to shove it

as tony and dad say get someone in with TWO brain cells in to service it properly

 

[ollski]

Sorry cm but I just don't believe that a qae advised you that was all you needed to do on an open flue....a numpty engineer maybe. I certainly never did less than a full service on an open flue during my Bg days and neither did any of theguys I worked with...there would be no way you could afford to with the postcomplete checks and all the rest. A standard open flued boiler is a doddle to service anyway...nothing to them is there?

Is this a proper service when the burner assembly is withdrawn and cleaned ?

Or is it a British Gas "service" which is only a safety check?

Tony

Its not on an open flue Tony it is a full service every time...allowing for the variation in indivudual engineers of course as with everyone.

sorry to disagree oll but thats ****

they just stick the FGA probe up the draft diverter, if the reading is below .004 they do nowt

they do do spillage and FF if your lucky but FULL service dont make me laugh

Believe me THATS how they told me to carry out a service on an Ideal Mexico when I sub for them, it was at this precise moment I told em to shove it

as tony and dad say get someone in with TWO brain cells in to service it properly

 

[corgiman]

Sorry cm but I just don't believe that a qae advised you that was all you needed to do on an open flue....a numpty engineer maybe. I certainly never did less than a full service on an open flue during my Bg days and neither did any of theguys I worked with...there would be no way you could afford to with the postcomplete checks and all the rest. A standard open flued boiler is a doddle to service anyway...nothing to them is there

Thats cos your a top man, but believe me thats what they say

they seel it as a "safety Check" NOT a service.

gets aint they

too many services and not enough blokes to do them

 

[croydoncorgi]

A standard open flued boiler is a doddle to service anyway...nothing to them is there?

Sometimes!

I spent 2.5 hours getting the soot out of a balanced-flue Mexico last week!

It was only when I got the HX unblocked and a reasonable flame picture that I discovered the original cause of the sooting - a tiny, tiny leak on one side of the HX that was causing enough flame-chilling to soot it up completely over a couple of years! An FGA probe up the terminal would probably NOT have found anything unusual at end of year one but it was completely choked up towards end of year two!

If the OP's boiler is suffering suddenly from poor / delayed ignition, there could be a number of causes, which need to be identified and fixed by a competent person, especially given it's an open-flue type and at least the cat is in some danger!

 

[fitz1]

there seems to be less than 85% oxygen there.could be a combination of clogged hx and lack of ventilation.

 

[jumbo55]

for what its worth, bg advertise a safety check every year for all boilers under their insurance, so they are not pulling the wool over the customers eyes. but as an ex bg engineer, i can honestly say that you were told to do a full strip down service on all open flued boilers, for obvious reasons. as with every firm.. you do get your rogue employees, wether working for or outside bg.
i can tell you that i was called out many times to go over contractors work when i worked for bg. i found the contractors cherry picked the jobs they wanted to do.
i cant understand why people slag off bg engineers, there are some good.. some bad, some new and not so good, some old and very experienced. but as i say, thats the same wether you work for them or you work for yourself.
lastly we are hearing all the time about engineers messing up a job and charging the customer even though they havent fixed the boiler. then the customer cant get them back, the bg engineer has nowhere to run.
so come on lads... how about it, a guy goes out fixing boilers for a living, same as yourselves, and because he works for bg, you slag him off. is that fair????

 

[corgiman]

I werent actually having a go at the lads on the "coal face" but at the middle management trying to manipulate figures to make themselfs look good at the expence of the engineer.

I find that the biggest threat to safety nearly always comes from middle management, I remember working for a firm years and years ago and being told that I was taking too long to service J&S warm air units (beleve me they were manky to the max) I said "they take as long as they take" to which the area manager said "look we all know the score, whop the hoover round it and get out" Alas he recieved my notice to quit then and there

shocking aint it, even more shocking when, if you think about it, the tie and suit wearing moron in his company car will sit there tutting and slopying the blame to the poor grunt if anything went wrong