Eggy smell from gas boiler???

[Inverness]

hi guys had a customer on the phone about the boiler producing a eggy smell?? I’ve been round with my gas sensor and flue gas analyser around the flue but all good! He read online something about the burner producing this eggy smell?! It’s all new to me. The boiler was not in use for a few month as the place was getting decorated. I though it might be the paint on the walls but they left the boiler running over one night and return home and the kitchen was stinking.. any advice please

 

[Scott_D]

Call the gas supplier
They can test properly for carbon monoxide etc

 

[king of pipes]

What boiler was it ? had a ideal icos with a partially blocked sump which smelled pretty bad just a thought . Kop

 

[firemant]

Call the gas supplier
They can test properly for carbon monoxide etc

Who do you actually mean? Gas suppliers don't do gas work, and the emergency service (NG/Cadent etc) dont carry FGA's. They only check for gas leaks.

Unless something has changed.

 

[Scott_D]

Who do you actually mean? Gas suppliers don't do gas work, and the emergency service (NG/Cadent etc) dont carry FGA's. They only check for gas leaks.

Unless something has changed.

If you have done all the tests you can I would advise the home owner call the grid. They have better gas sniffers, carbon monoxide detecting equipment.

 

[Last Plumber]

hi guys had a customer on the phone about the boiler producing a eggy smell?? I’ve been round with my gas sensor and flue gas analyser around the flue but all good! He read online something about the burner producing this eggy smell?! It’s all new to me. The boiler was not in use for a few month as the place was getting decorated. I though it might be the paint on the walls but they left the boiler running over one night and return home and the kitchen was stinking.. any advice please

Read up on Hydrogen Sulphide. Tell the customer not to use the Boiler until the source has been identified and dealt with.
That's my advice.

 

[firemant]

If you have done all the tests you can I would advise the home owner call the grid. They have better gas sniffers, carbon monoxide detecting equipment.

No. They dont have CO gear. But their gas sniffers are awesome.

 

[Last Plumber]

No. They dont have CO gear. But their gas sniffers are awesome.

They won't get involved in the investigation side of very much. They tend to make safe and advise you to get a GSR Engineer to do the rest.
The CO detection equipment I have seen them use in my area is for their own personal safety. Air quality monitoring in industrial premises or plant rooms etc is where I have seen them most. I don't know what they do in other areas of the country.

 

[Inverness]

vokera linea combi. There's a co alarm directly above the combi that hasn't been activated. I used my anton gas sniffer and there was no gas leak.

 

[Rob Foster]

our bed often has an eggy smell
maybe I will get Angela tested its okay when I go up,1st
centralheatking

 

[Inverness]

After a jar of pickle eggs washed down with fizzy coke

 

[firemant]

They won't get involved in the investigation side of very much. They tend to make safe and advise you to get a GSR Engineer to do the rest.
The CO detection equipment I have seen them use in my area is for their own personal safety. Air quality monitoring in industrial premises or plant rooms etc is where I have seen them most. I don't know what they do in other areas of the country.

Ihave no idea of the industrial stuff, but, yes, they may now have personal CO alarms, as I do. But they do not carry kit to repair boilers or investigate CO issues. TOFO is their remit.

 

[Burger]

Carbon Monoxide is odourless and tasteless hence the nickname “the silent killer”. Just sayin’

 

[firemant]

Carbon Monoxide is odourless and tasteless hence the nickname “the silent killer”. Just sayin’

Haha. good point. The decorator probably dropped his egg sarny behind the boiler

 

[Gold Gas]

I got called to something similar, it turned out to be the washing machine lol.

Most co alarms should be between 1 and 3 metres from the appliance, if its directly above might be too close, just for future reference.
Let us know if you find the source of the smell.
U sprayed the burner test point on the gas valve?
Is the flue close to a window? Poc can smell or any unburt gas

 

[Last Plumber]

Carbon Monoxide is odourless and tasteless hence the nickname “the silent killer”. Just sayin’

You are quite right, it is.

Hydrogen Sulphide is also dangerous. It is a corrosive gas with a similar toxicity to CO.

It 'could' be present where a faulty boiler is concerned and therefore CO 'could' also be present.
I personally would not want either of those two near me for very long, whether they are alone or together.

Either way, if there is a rotten egg smell, chances are it is Hydrogen Sulphide and needs dealing with whether it is alone or with its associates.......(they have other friends).

 

[firemant]

What boiler? Open / balanced or fan flue?

 

[Inverness]

Balance flue.

 

[SJB060685]

@Last Plumber can you tell me about hydrogen sulphide. I know what it is and it’s effects on people and the environment but unsure of its relationship to natural gas. Is it found in the gas and not removed while being refining or is it a POC?

 

[Last Plumber]

@Last Plumber can you tell me about hydrogen sulphide. I know what it is and it’s effects on people and the environment but unsure of its relationship to natural gas. Is it found in the gas and not removed while being refining or is it a POC?

I'm no Chemist so I don't know that much about it. It is found in Nat Gas but there is not much left after the refining process as you probably know. They also add an odour to it here so we can smell it. I don't think we would smell the small amount of H2S over that to be honest.

It does effect the inside of copper tube by reacting and producing copper Sulphide? as I said, not a chemist but I think that's right. Feel free to correct me if I'm wrong.

When I was thinking about the smell of rotten eggs in relation to this boiler above, I was thinking of the times I have come across that pungent smell from boilers I have worked on (inside them though, never outside). I have noticed it before but only in certain sections. I have noticed it with solid fuel stoves, or oil Boilers, less so for natural gas but I have noticed it on opening a sump which has rarely been cleaned out and full of deposits. That's why I was thinking of leaking heat exchanger sumps or condensate drains?
I think it is bacterial reduction of Sulphur that releases the Gas.

My thought was that if it is coming from inside the boiler combustion chamber, flue, sump or condensate pipe (before the trap), it could also have POC's with it.

It may well not be H2S from the Boiler. It could be a dead rat or a dead bird up his chimney or stagnant water but it reads like it is only there when the boiler is on.

Does my thinking make sense?

 

[SJB060685]

Thanks for reply. Yes like you say H2S is found within the supply of gas, varies from where abouts in the country as a quick read suggests it’s common to have a higher concentration further north (not sure how accurate that is). Like you say I would imagine if it was coming from where you mentioned above then it would have POC’s with it and all are a possibility.
I’m going to have a more in depth read later.

 

[dan_the_plumber]

If it’s a ‘room sealed appliance’ and the seals are ok, then it can’t release POC into the room.
So I’d say either you have a hole in the condensate pipe, or the POC is re-entering the building via a window or vent.

 

[firemant]

If it’s a ‘room sealed appliance’ and the seals are ok, then it can’t release POC into the room.
So I’d say either you have a hole in the condensate pipe, or the POC is re-entering the building via a window or vent.

Are there any Condensing Balanced flue boilers?

 

[Chuck]

H2S gets oxidised by combustion and contributes to the SO2 in flue gas, which doesn't smell eggy. Gas hobs don't smell eggy, for example and their POC vent straight into the cook's face.

I'd be looking at the drains for a leak or untrapped sections that have slime from a washing machine outlet, that sort of thing. Are there any sections that would have got warmer than normal when the boiler was left on continuously overnight?

In some circumstances, the calcium sulphate in plaster can provide the sulphur needed to produce H2S but this is towards the bottom of a list of possibilities that has 'Drain Problem' at the top.

 

[Gazzzz101]

I have my CMDDA, and do carbon monoxide investigations regularly, as previously stated CO doesn’t smell, you’d only get a smell from the gas if it’s leaking or unburnt, the smell could be from the radiators if the system hasn’t been used for a while, or maybe worth tracing the condense and seeing where that’s connected?

 

[Inverness]

There's no condensate on this boiler.

 

[DjClubber]

Condense???