Rotten egg smell Vaillant ecotec 837 boiler - bacteria?

[deev256]

I had a brand new Vaillant ecotec 837 boiler fitted in June and ever since then there have been intermittent rotten egg smells coming from the boiler. There are no hot water outlets in the room where the boiler is, it seems to emanate from the boiler/boiler cupboard itself.

The gas safe engineer who fitted it came out and checked it over and said it’s fine, as well as fitting a carbon monoxide alarm. I had a national grid engineer out to check the meter and boiler, who again said it was fine. I contacted Vaillant and another engineer came out, who again said it’s not the boiler and all was ok.

I’ve eliminated the drains (just outside of the room where the boiler is) as the source of the smell. I’ve also been keeping a ‘rotten smell log’, and the smell starts quite strongly at around 9 am after the boiler first comes on. It then comes and goes throughout the day.

[FONT=&quot]I’ve been looking online for an answer and the only thing I can find is sulphur reducing bacteria which can make these smells, but from what I can fathom this doesn’t usually occur in combi boilers which as far as I know are sealed systems. I’m kinda getting desperate for a solution, the smell makes the room very unpleasant to work in! Can anyone provide a definitive answer? [/FONT]

 

[Penged]

Hi
As your boiler is still under warranty, call vaillant make sure when the engineer comes he uses a gas analyser, all round the boiler and along all pipe work, make sure they come around or better yet just before 9am, by the way are you a terrace house I ask because it maybe your neirhbours boiler.

 

[deev256]

Hi,
When the Vaillant man came he used a gas analyser, as did the plumber who installed the boiler and the national grid-man. None of them came when the boiler was emanating the smell though, but i would assume that if it was gas then it would make no difference, it would register to some degree what ever the time. We're a stand alone building too, no boilers near the offending one. Only drains outside but they're fine...
Cheers

 

[Penged]

Hi
Have checked your drains,you're right if it was gas it should be evident at anytime, did you have anyother building work done at the same time or soon there after, slowly comb the area again check any foliage from outside that maybe trapped near the kitchen or were boiler is as this could be rotting slowly, it may pay to get drains roded as some foliage may be trapped further down the line. Anyway hope you find the answer soon.
All the best.

 

[SciencenotPlumb]

Rotten egg smell would be typical of Hydrogen Sulphide (H2S) which your nose can detect at very low levels. I've noticed this smell at times from old plumbing fittings. I always assumed it was impurities in the solder reacting with the water. You could hire yourself a Drager gas detector, but you could also try taking something silver (a silver teaspoon?). Polish it nice and bright, then wash it in hot soapy water to remove any inhibitors the polish leaves behind and place the spoon close to the suspected source for a day or two. H2S will tarnish the spoon and you should see the exposed surface go dull black. The downside face should stay bright.

 

[deev256]

Ok i'll try the silver spoon test this week, cheaper than hiring a detector! Assuming that there is a presence of H2S, where's it coming from though? I wouldn't have thought it'd be from the water in the central heating circuit as it's a sealed system. What impurities in old solder can react with the water, and how would that smell escape? As i said too, it's a brand new boiler...the rads on the central heating are old though, as are the large bore steel pipes connecting them.

 

[Penged]

Me again
Try bleeding one of the rads and smell the air it gives off, did you powerflush always best if you have old rads but new boiler, often h2's can get trapped, may need air vent to get rid of it.

 

[deev256]

Hi, yes i bled the rads this morning. The air smelt a little metallic but nothing out of the ordinary. The guy who comissioned the boiler powerflushed etc, and installed a magnaclean device. I'm going to give the drains the once over again just for my own peace of mind but at pretty sure it's not them. I thought it could be the paint on the wall the boiler's mounted but the previous boiler didn't emanate any smells and it was in the same place.

 

[Blackcatgas]

Has the flue been sealed internaly and externaly.

 

[RobTi]

Any open pipes from the old instalation that have not been sealed ?