Boiler Exhausting Gas... maybe

HappyIdiotTalk

Our boiler's exhaust smells a little gassy. Is it possible it could be exhasuting unburnt gas? And if so is this normal or is it just costing me a load of money?

I've only just noticed this and fortunately the insurance firm we have sent out an engineer yesterday to check it over. I asked him about it and he said that its possible its venting gas, and it could be because its so dirty inside it - and has advised we get it cleaned. But he didn't bother going outside for a sniff and didn't really seem very confident about what he was telling me and so I'm not that confident in what I've been told.

Is this something to be worried about, or is it normal.

Many Thanks!

Avoriaz

Most gas boiler exhaust is a bit whiffy but you should get it checked out by an expert.

Get a local Corgi registered firm in for advice and don’t let them con you into a new boiler unless you really need one.

Actually, if you do not have a condensing boiler already they are a good investment and you can recover the cost in a few short years as they are far more efficient than non condensing boilers.

ajsdoc

Do these condensing boilers really save money though? I know they are likely better for the environment. Seems to me the old cast iron boilers with a pilot light go for years needing only the odd thermocouple (mine certainly gives no bother). The new type boilers owned by people I know seem to have a much higher breakdown rate requiring much more expensive parts than a trusty "old style" boiler. I'll not be changing until forced.

Canucklehead

Hi

If you have an older boiler then it's quite likely that the gas valve is letting by very slightly,(but not enough for the pilot to ignite)
It's easy enough for an engineer to check (leak detector fluid in the right place will show it up straight away.)
You should not have a smell of gas anywhere.
You should have it looked at again and get a definitive answer.

Condensing boilers...............

Try looking at it another way
It is not necessarily a question of saving money but how much GAS you will NOT be consuming. The more you use today the less there will be tomorrow.
It's up to you.
Plus consider the difference in flue temperature 180 odd degrees c for a non condensing as opposed to about 50 degrees for condensing .Times that by millions of boilers. The argument for global warming is looking quite convincing at the moment don't you think? Given the weather.

Perhaps this should have a thread of it's own!!!!

Corgi Guy.

Avoriaz

ajsdoc wrote:

Do these condensing boilers really save money though?...

Yes they do. They are so much more efficient than non condensing boilers that you can easily save the cost of it in a few years. You would have to be very unlucky to spend more on repairs than you save on gas.

From memory a typical condensing boiler is about 89% efficient compared to maybe 65% - 70% for a non condensing type. Do the sums on your gas bill.;)

alanobrien

Avoriaz wrote:

Yes they do. They are so much more efficient than non condensing boilers that you can easily save the cost of it in a few years. You would have to be very unlucky to spend more on repairs than you save on gas.

From memory a typical condensing boiler is about 89% efficient compared to maybe 65% - 70% for a non condensing type. Do the sums on your gas bill.;)

It would be nice if it were that simple.
The old boiler in this house was some 20+ years old when we moved in.
It cost a fortune to run and i replaced it with a condensing type which is far more economical to run BUT............capital cost for condensing is higher, life expectancy is shorter and repair is more costly than for an old conventional boiler.

Factoring that lot into comparitive cost calculations would be interesting.

Personally the alleged "greeness" of a condensing would sell it to me every time, but real cost comparison is a complex subject.

Avoriaz

It is indeed a complex subject though most experts believe you are better off with a condensing boiler.

And the law now insist we only buy and install them so that more or less makes the decision for you if you need a new boiler.

Extracted from the second link on this google search

http://www.google.co.uk/search?as_q=condensing+boiler&hl=en&num=10&btnG=Google+Search&as_epq=efficiency&as_oq=&as_eq=&lr=&as_ft=i&as_filetype=&as_qdr=all&as_occt=any&as_dt=i&as_sitesearch=&as_rights=&safe=images

“By law most new gas boilers fitted in England and Wales must now be high efficiency condensing boilers (with a few exceptions depending on suitability). High efficiency condensing boilers can be easily fitted to most new and old heating systems, ask your installer for more details.”

Ironically, my boiler is a normal boiler installed in 1993 and despite preaching the merits of condensing boilers, I have not yet installed one myself.:o

I keep saying next year.:D

HugoSP

Our boiler occasionally smells like this.

However it is checked on a regular basis and is only 2 years old.

The smell associated with gas is actually thanks to an odourant introduced to make it smelly, so that you and I can sniff out a gas leak.

Hence I thought it was the odourant that I could smell, not the actual gas.

HappyIdiotTalk

HugoSP wrote:

Our boiler occasionally smells like this.

However it is checked on a regular basis and is only 2 years old.

The smell associated with gas is actually thanks to an odourant introduced to make it smelly, so that you and I can sniff out a gas leak.

Hence I thought it was the odourant that I could smell, not the actual gas.

I was wondering if that could be the reason. I would have expected higher bills if the gas was escaping too. Thanks.

Canucklehead

Hi

You would never notice a leak of that size on your gas bill!!
By the way how old is the boiler?

Corgi Guy.

andrew-b

When we moved into our house a few month back we had a 13 year old baxi boiler in the kitchen with "powered flue" that was a bit more smelly outside the flue than you'd expect - mainly when it started up though. I noticed that the boiler was taking far too long to light itself. Within a few weeks the boiler went from taking 5 minutes to light to sometimes 30 minutes and once or twice not at all.

As we were about to install new kitchen it made more sense for us to replace the boiler than waste money on fixing and having to replace it later and mess up the new kitchen. After 5 quotes we got swale heating (not the cheapest quote) to replace the old boiler with a Vaillant condensing boiler that claims to be 91.2% efficient. I wouldn't bother again with british gas who were our fifth quote - the salesman they sent me was so incompetent it was beyond a joke and i nearly spat my coffee out all over him when he gave me a price.. i got rid of him fairly quickly after the price! He even had the cheek to offer me credit to make it even more expensive!

When removing the old boiler the heating engineer showed me the joint on the flue with the boiler was all black where he suspected fumes had been leaking out into the kitchen. He also showed me a carbon monoxide detector sticker hidden on the side of the boiler that had turned completely black! Just as well we replaced it as it was slowly poisoning us! Carbon monoxide is completely odourless though so unless you have a carbon monoxide detector there's no way of knowing. One of the other clues to its safety (or lack of in this case!) is the colour of the flame...ours was nearly completely orange when it should be a purply blue colour.

Just goes to show you REALLY must get your boiler serviced just after you move into a house (even if the previous owner says they've had it serviced regularly which is exactly what was said to me!) and then annually thereafter. If you suspect anything wrong with the boiler get a CORGI registered heating engineer out as it's just not worth the risk At the very least have a carbon monoxide detector or even just spend a few quid on some carbon monoxide stickers and make a habit of checking them regularly and replacing when necessary.

As well as reducing our gas bill the other noticeable bonus of a condensing boiler has been that because these types of boilers are so efficient the heat is transferred much more quickly to the hot water cylinder and radiators. Our average size bungalow can be warmed up in less than 10 minutes now.

One disadvantage that's worth consideration before getting a condensing or combi boiler installed is pluming from the flue. Because of the pluming effect we couldn't have a horizontal flue as it would have plumed over the fence only a short distance from the house and would probably have misted up the neighbours windows...so instead we had to have a vertical flue going up through the kitchen ceiling and out through the roof which added to the cost a bit.

Andy