fumes from boiler

[mickandy]

We have a Glow-worm FLEXICOM 15hx condensing boiler installed in the airing cupboard on the upstairs landing.It is behind a door which has vents at the top and bottom.The boiler itself is vented straight through the loft into a pipe on the roof.
Whenever we have a shower and turn on the extractor fan we are getting a foul smell which seems to be coming from the airing cupboard. We have checked the drain pipe for the boiler and it is clear.The bathroom is located on the same landing about 8 feet away from the cupboard.
It has not always done this and the boiler was installed in April 2008 by a competent heating engineer.We have had the problem for approx 6 months now.
However we have contacted him about this problem but it seems no one can come up with a reason for the smell or where it is coming from.
It goes off slightly when a second shower is employed.
It is an awful smell and goes right through the house.The rest of the time the boiler works perfectly. It just does not get along with the shower and the extractor fan!!!!
Please help as we are getting desperate to solve this very smelly annoying problem!
My thanks in advance
Andrea

 

[dontknowitall]

Sounds as if the boiler isn't receiving enough ventilation.

If it isn't getting enough air you are in serious danger of dying from carbon monoxide.

There are rules and regulations concerning this. Basically anything more powerful than a 5Kw heater requires a certain amount of permanent ventilation otherwise it is deemed to be sucking too much air from the house.

When your shower extractor fan is on the oxygen from the house is being pulled to the fan and as the boiler has no ventilation of it's own then it can't breathe properly.

When there is enough air (O2 - oxygen) boilers exhaust gasses contain CO2. If the boiler is starved of air, then boiler emits CO instead. You can't smell carbon monoxide and (in case you didn't know) it's a lethal gas.

When your shower extractor fan is on it is pulling oxygen from the house and then the boiler (assuming it's not got it's own permanent ventilation) is not breathing properly so it is trying to suck any air available, in this case the air from your bathroom.

Methane is CH3OH and I assume this is the smell. The boiler is using the steam from the bathroom (H2O) to get its oxygen and giving off carbon, two parts hydrogen, one part oxygen and leaving the remaining hydrogen in the air.

This of course might be total codswallop but it sounds good!!

A clue - have you or family been getting headaches or feeling more sleepy than normal sometimes since the new boiler has been installed? If you have, this is a sign the boiler is not vented properly and you have very dangerous set up - one which could kill you.

It sounds dramatic and dangerous and it is. This is why we go on courses - to find out about these things and learn how to avoid these situations.

 

[mickandy]

Thanks for such a quick and informative reply. The boiler is vented through a large plastic pipe from the top of the boiler which goes from the airing cupboard through the loft space and out into the air via a small chimney pipe.
We have suffered no headaches at all.
The smell I don't know how to describe,a bit like rotten eggs maybe?
This problem only ever occurs when we have a shower.
We have checked out the pipe that drains the water from the boiler,it is clear.This pipe runs into the same drain area as the shower (outside) and it too is clear.
The smell seems to come from the top of the boiler. Is it worth getting in the loft to see if the problem could be there?
Thanks once again.
Andrea

 

[dontknowitall]

First I don't do gas but ... !

The large plastic pipe ...

Is this the flue (ie the chimney) for the exhaust gases? If it is I don't think it should be plastic because of the heat involved. In oil and solid fuel heating the flue has to be a certain material, size and straightness. I assume this also applies to gas installations.

If this is so then the flue going from a large tube/pipe to a small tube/pipe is installed incorrectly and what could be happening is the exhaust gases are being trapped and so they are not leaving the house.

The ventilation I was talking about is different. It's effectively the ambient air intake for the boiler. A boiler needs air which it takes from the house (5Kw) plus a suitable sized air brick or similar.

This "ventilation brick" is usually found near the boiler and will create a direct airflow from outside the house to the boiler.

Smells ... methane is like marsh gas .....


Blah ... blah ... just been reading stuff on internet - and now I'm totally confused!!

Natural gas is odourless so sulphur is added to gas to make it detectable to the human nose. This creates the smell of rotten eggs.

It sounds as if you either have a gas leak, or poor ventilation or a poorly installed flue (or all three!)

Hope this helps!

 

[mickandy]

The pipe fitted came with the boiler from Glow-Worm so possibly it is not plastic but white coated metal.
It is a sealed unit and only vents through the roof chimney.
Thanks for trying to help us out.
Andrea

 

[Cds]

A few possibilities:

1) The boiler is room sealed so take its air from the twin walled flue. Flue gases are nearly odourless so it seems unlikely to be these causing the smell.

2) Natural gas (methane) is odourless but a smell is added so that it is detectable should there be a leak. If the smell is like rotting vegetation to rotten eggs then it could be gas. If there is a possibility that this is gas then TURN THE GAS OFF AT THE METER and get it looked at.

3) Another possibility is that there is a problem with your waste /soil pipes. When the fan is on in the bathroom or when the shower is running foul air from the sewage system is being pulled or pushed into the airing cupboard.

What ever the cause I would get your installer back to look into and resolve the problem.

 

[derrybongo]

a few questions :

do you still get the smell with the extractor fan off and the shower on

do you still get the smell with shower off heating on and extractor fan on

do you still get the smell from any of the hot water taps

do you still get the smell with the burner on full on central heating mode while standing next to the boiler

might help narrow things down a bit

 

[migoplumber]

best to turn off immediateky, and get an engineer on site 2mrw urgently. could be trivial but if its not it could kill you. INTERNET ADVICE IS NO ADVICE IN THIS CASE.

please get your installer back on site to deem your appliance safe for use.

 

[Billy Bob Bob]

Sounds as if the boiler isn't receiving enough ventilation.

If it isn't getting enough air you are in serious danger of dying from carbon monoxide.

There are rules and regulations concerning this. Basically anything more powerful than a 5Kw heater requires a certain amount of permanent ventilation otherwise it is deemed to be sucking too much air from the house.

When your shower extractor fan is on the oxygen from the house is being pulled to the fan and as the boiler has no ventilation of it's own then it can't breathe properly.

When there is enough air (O2 - oxygen) boilers exhaust gasses contain CO2. If the boiler is starved of air, then boiler emits CO instead. You can't smell carbon monoxide and (in case you didn't know) it's a lethal gas.

When your shower extractor fan is on it is pulling oxygen from the house and then the boiler (assuming it's not got it's own permanent ventilation) is not breathing properly so it is trying to suck any air available, in this case the air from your bathroom.

Methane is CH3OH and I assume this is the smell. The boiler is using the steam from the bathroom (H2O) to get its oxygen and giving off carbon, two parts hydrogen, one part oxygen and leaving the remaining hydrogen in the air.

This of course might be total codswallop but it sounds good!!

A clue - have you or family been getting headaches or feeling more sleepy than normal sometimes since the new boiler has been installed? If you have, this is a sign the boiler is not vented properly and you have very dangerous set up - one which could kill you.

It sounds dramatic and dangerous and it is. This is why we go on courses - to find out about these things and learn how to avoid these situations.

its room sealed mate does not need ventilation,takes its combustion air from the flue

you need to stop using this boiler immeadeatly it has a design flaw on the combustion gaskett [it breaks down without warning] there is technical updates
via gas safe this is what your smelling turn it off,call a engineer or your gas supplier on 0800 111 999

 

[stevetheplumber]

if it subject of technical update from gas safe you can probably get gloworms to come and replace it foc so after turning it of ring glowworm

 

[Billy Bob Bob]

thats very true steve,problem is if fumes can be smelled it has allready wrecked the heat exchanger this problem also affects vailents

 

[mickandy]

The shower is electric and the switch for it is in the airing cupboard. It is a 10.5kw shower.
The plumber came this morning and we went through the normal routine of running the shower with the extractor running also the boiler.
He wanted us to run the shower with the boiler OFF so we did. The smell started up and he then felt the shower electric switch which was getting very hot. He then removed the cover to discover there was a loose blue wire which had signs of burning.The cable and box was fitted by a qualified electrician as the shower was updated when we had the bathroom done.
I used to smell burning when I laid in bed sometimes but assumed it was coming from outside.
We are hoping we have solved the problem!!
I want to thank you all for your suggestions and will let you know if this problem has been solved at last.
Kind regards and a big thank you
Andrea

 

[dontknowitall]

Thanks for telling us what the problem was. It's amazing how many don't say how they fixed things which means more people tootle along here and ask the same questions!!

 

[mickandy]

Problem solved it was the cable shorting out that caused the problems.
All fixed now.
Many many thanks for being there when we were getting no where!!
Tried Gloworm for help but all they were interested in was charging us to speak to a technical adviser or charging call out fees etc etc. They then had the cheek to ring later and tried to flog us an extended warranty!!!