Partially blocked chimney flue.

On Tuesday 09 April 2013 13:10 snipped-for-privacy@googlemail.com wrote in uk.d-i- y:

Removing bricks at the level of the blockage, whilst tedious, is probably the best bet.

On Tuesday 09 April 2013 13:10 snipped-for-privacy@googlemail.com wrote in uk.d-i- y:

Another idea is to get a cheap USB camera with light and long cable and send it up tied to the brush and see what you are up against.

a 5m cable camera should do it - I'm about to buy one for my drains...

I'm just about to order it - can let you know if it's any good - or you can borrow it if you are near East Sussex/Kent (Robertsbridge).

Could it be birds nests etc?

Its a pity nobody has a chimney brush with a camera on the end, at least then you could see what it actually was.

Brian

I suspect the heavy weight option will be chosen by whoever installs the liner. They often used slates to divert the smoke in a particular direction, and generally these weren't well secured. Can't remember the technical name for them.

a blockage where the chimney passes throuh the attic; impossible to get a b rush past. I've ignored it for years but want to install a liner so need to clear it. Suggestions so far: go on roof and drop heavy weight on rope dow n pot to dislodge blockage (not keen on that as my legs wobble above gutter level); measure with rods to find exact height then take out brickwork to find and remove obstruction (which sounds like hard work). Any thoughts?

It might only be jackdaw's nest. You need to establish where the blockage is and remove bricks if it can't be dislodged. It needs fixing, you shouldn't use it until the problem is resolved.

Or GSI (Get Someone In)

I demolished all my chimneys to ground level. They were all built with a "wiggle" , presumably to reduce the draught generated

Hmm. You might want them back one day.

Or to stop rain falling down them.

Andy

That does limit your options.

Drain rods with screw on end would be my thought - if it's a nest you might be able to pull it up. As in

... except the one on my Dad's set is much smarter than that one.

Andy

The 'wiggle' you refer to is a purpose built draught *generator* not reducer - a flue doesn't draw properly if it's not bent

it's 90% certain that it's a brick that has become dislodged, probably from the mid-feathers - the single brick walls that seperate flues inside a stack.

Might be as well taking a few bricks out inside the loft area, but take them out *above* the blockage then you can pull the brick upwards

Good advice, where this happens in multi floored Scottish tenements and the blockage is found not to be in friendly territory the norm is to repeatedly drop a sash weight on a rope onto the obstruction to see if it will clear down the flue.

Care to expand that a bit? How does it do that?

Chris

Yes, could be that too. All the bedrooms had fireplaces even. They had hardly been used though the place is seventy years old and must have been freezing cold in Winter.

Well I have demolished lots of chimneys without.

I suppose it might make the chimney longer and increase the draught but I'd have thought the effect would be more than offset by the increase in resistance.

If a chimney is longer, it increases the draught. But if it is narrower, rougher, has bends or is cooler, that reduces it.

I think it's probably some tradition/old wives tale, you never see it in modern chimneys.

I thought quite a lot of chimney wiggles were simply how the flu parts were built so that, say, two fireplaces on each of two floors, come out as one chimney stack with four pots on a roof - and none of them is directly over any of the fireplaces!

My place is a bungalow. The inlet and outlet to the wiggle were exactly in line. The rain theory sounds plausible to me.

a blockage where the chimney passes throuh the attic; impossible to get a b rush past. I've ignored it for years but want to install a liner so need to clear it. Suggestions so far: go on roof and drop heavy weight on rope dow n pot to dislodge blockage (not keen on that as my legs wobble above gutter level); measure with rods to find exact height then take out brickwork to find and remove obstruction (which sounds like hard work). Any thoughts?

Thanks all replies - esp. Tim for camera loan offer. I'm in Brighton so a b it far though. Interesting stuff on wiggle / draught relationship. My curre nt plan is to pay a more daring person to drop the sash weight as a first a ttempt. Will let you know...