Smelly Flue...What to DO?

You haven't been hiding dead birds in it by any chance? I noticed my flue smelling a bit and found that it was due to damp soot build up! I've tried the spinning hat but that didn't stop the rain getting in! Next I will try the one that looks like an open faced crash helmet with a fin attached to angle the opening away from the wind! I extended my flue by a meter and got a much better draw! Maybe you just need to clean the flue of dead birds and soot to get rid of the smell!

Birds, or rodents such as squirrels or other such critters are in there. You need a chimney sweep (someone who sweeps chimneys for $). Or DIY.

No No No...It is capped with a cheapo basic cowl, so I know there no dead critters or relatives of Kris stuck up there. I also know it's clean as I replaced it a few years back...

The 'extending the flue by 1 metre' is interesting.

Del

If your burner is running rich, it can soot up your flue very quickly. Stick you paw up into the flue through the barometric damper and feel around. If it comes back covered with soot....

I've had it checked out by a GORGI fitter who lives down the road so I know it's burning ok. (And the flames are the right colour)
It's ok when it's burning for longer and has a chance to get hotter.
BTW
When I refurbed the kitchen I was going to fit an extractor fan until I realised it would pull the flue gas through the kitchen.... I checked up on the Building Research Establishment website and found out that this is a major problem that people are generally not aware of! Any how it saved me some work of knocking a hole through the wall and I just set the cooker hood up to re-circulate through the filter.

Del

This is nothing to play around with. If you smell "been hot but unburnt gas", you probably have elevated CO levels. It would be great if you have access to a pressure gauge in the .0X range, and a flue gas analyzer. I borrow these from work each fall to check out my systems.

Extending you chimney by 1 meter will be a big help, whether the wind blows or not. However, if you can't borrow the equipment, pay and have the system serviced. The tech. will tell you if you need a sweep too.

Another alternative is to fly me over and put me up for a week or so. I'll do the service for no charge!

The hotter the flame, the more of an updraft you will get. When was the last time the furnace was maintained? Dirty burners etc. will cause the furnace to burn inefficiently. Are all the burners working?

How old is the furnace? need replacing? The last one I replaced only cost me $50 per month with free maintenance thrown in. Newer ones are more efficient and will save you fuel costs.

The others are correct in checking for blockages and cleaning the chimney.

Rotary ones are useless and birds will nest in them.

Come on Del. Get with the program. The only way you or Mrs. Del can smell any fumes, is if they are not going outside. At the very least, the flue is allowing cooled exhaust gases to come back down the chimney, and back into the house. CO2 meters are cheap, and lifesavers. How else can the smell come back into the house?

You need to find, and fix the leak. If the leak is not accessible to you, you can buy some time by turning on a fan so as to pressurize the chimney. This would stop the heavier exhaust gases from returning back. Once the system is good and hot, it will rise sufficiently to be caught by the drifting winds and moved away before it cools and sinks again. At this time you could turn off the fan.

Get the CO2 meter.

First thing to do is turn the boiler off at the time switch then isolate the gas supply to the boiler. Then contact your local CORGI registered installer and get a modern condensing boiler installed instead of your old open flue non-condenser. What you are smelling is almost certainly carbon monoxide which is a killer. Do not take the risk with your life. Replacing it with a condensing boiler will help the planet and reduce your running costs.

Thanks for your concern Gasman...
I am thinking about a condenser one...but I've heard bad stories about reliability, and my old cast iron one is fine...(I flushed it out a while back when I was fitting my home brew solar hot water panels)...so it's not a cost effective option at the moment.
Mind if those rippoff merchants at the gas suppliers hike their prices much further I'll have to.

My actual question is about flue cowls.

IF I get a condenser boiler I'd install it myself so I'd know it was done right (and then get it checked by a GORGI guy)...you wouldn't believe the crap I've seen gas,water & electrical done by 'registered tradesmen'

Del

You wanna watch them GORGI people - any dude can get a GORGI card, so you need to check the back of it to see what he/she is qualified to do. GORGI issue cards to people who are not certified in all aspects of gassy stuff. Condensing boilers are not as efficient as they might seem, max efficiency is when biggest temperature exists (like first thing in morning). Also, some are designed to fire up for brief periods during the day, and a slightly leaking hot tap can keep them on all the time. That was told to me by a fitter, so I really can't vouch for it - I couldn't be ***** to read the manual on my cheapo condenser.

Uncle Fester wasn't cremated in Harlow !

Can you refine the term a bit? "Smelly" is a bit vague. And my cat always liked the things that stunk the worst, anyway...

It won't hurt you to install a CO/CO₂ alarm as a precaution. Though odorless, they often come along with other things, so you can't rule them out just because the flue stinks. Have you looked at ventilator caps like this for your roof jack? After you raise the height a meter, might as well splurge a bit, eh?

Yup that's exactly the sort of thing I'm actually asking about...anyone any experience of specific ones?

So far, I'm looking at the taller stack option...(and maybe a Canary to check for gas of course)

Del

Y'ain't foolin' nobody, ya want a canary fer snackin' purposes! The ventilator cap as shown works well. At least as effective as the turban (turbine?) style. And provides a rain/bird/skwirrel keeper-outer as well. Wouldn't one of these do?

If you can assure that your system is functioning OK, the most cost effective solution would be to ad that 1 meter section to the flue.

I have a friend who had a similar problem. He had a contractor come in and recommended a blower and a cold air pipe.The quote was over $3000!. I check out his flue, almost 0 draft cold. Once heated up about .02". I put up a 4' section of stove pipe on the chimney for a test. He lives in a cape, 1 floor, so the 4 footer increased the chimney length by about 25%. We got about .01" cold and .03" hot. That's a huge improvement! He installed a permanent extension, (about $100), and hasn't had a problem since.

After careful consideration, I feel I have come up with an even more expensive solution. Sell the house and buy a new Pay some one to tear your house down. Pay through the nose to stay in a hotel and rent storage space for your belongings. Buy new cloths because it is too much bother to get additional cloths from storage. Have a new state of the art house built that can operate entirely on thermal energy, Geothermal energy, wind power and finally harness the rotation of the earth.

Yea that should about do it. NO WAIT. Hire an overpriced mover to move your belongings and break the expensive ones. Yea thats it. Now look at the money you will save.

I'm considering one of these ... H cowls, whadda ya think eh? eh?
The price is reasonable.
The actual electric flue fans are silly money, about half the price of a new boiler...The rotary cowls are about £80, but I don't see how they help if there is no wind?
The H cowl is about £55 which isn't a mad price (cheap compared to the golf club I just bought...shhhh Mrs Cat will hear ).

C'mon guys opine if you would.

Del

What about putting a hydrogen generator on top of the flue? We already know these devices suck.

The "H" flue top must work pretty well, I've sure seen enough of 'em about that are in use. But don't discount the rotating model - any rising heat will make it spin, and that increases the updraft. For 50% more £ you might get 50+% more draft, so at least check out the claims made on 'em. I agree an electric fan is silly money, but only if you spend it. If you collect it, it's pretty serious change.

No better'n you golf, you might just as well trade the club for one of the spinners and get some of the fuel costs back in the bargain as difference...

No, I don't think this is your answer, (the H-cowl). I believe it's designed to prevent downdraft, and I don't think that's you problem.

Del

Sometimes there will be some carbon or soot built up in heat exchanger just below the flue connection. A mirror from below or removing flue assembly on top of boiler will tell the tail. If it is fin & tube the fins could be plugged & causing a 'roll-out effect'. Do any of the wires, gas valve, or controls have a discoloration to them?

Good luck & don't spend alot of money on maybe unnessesary items yet.

I think I'll open it up and give it an Autumn clean...
I'll report back if I find anything exciting....maybe a stash of pirate treasure blocking the flue...Arrrr

Or more likely Kris' cousins' stash of acorns...

Well we know the rottenegg smell so it is not a gas leak I am guessin.

A neighbor had a Raccon who would come and sit on top of the Chimmeny and block his flu. The smoke would back up and fumeagate his home weekly. Rocky Raccon got a new home !

Thanks guys for all the help.

I looked at my records and found it was 2005 whaen I refurbished it...and some furry idiot hadn't serviced it since.

Anyhow close inspection showed the little gas pipe which feeds the pilot had become loose in the olive which grips it, there had been a slight leak giving a sooty yellow flame below the pilot light this had caused a lot of soot up through the matrix on one side and in the chamber above it.

I tightened the olive (we actually I tightened the aluminium pipe onto the olive), and cleaned the whole lot out, stripping down the burners etc. Put it all back together and it's burning nicely. I lit a smoke match and the smoke all drew up the flue nicely with none spilling out the draught diverter at the back.

Of course tommorrow morning it may still smell, but at least I'll know that all the fundamentals are right.

Cheers
Del

It still could be some of that acorn coffee...

Del, Del, Del... There is your problem right there! Olives are for martinis! Not gas connections!