Disused boiler flue leaking fluid

[JenniferB]

Hi, We have a boiler flue which is no longer used as the boiler was moved.

The flue goes up the chimney, and in the cupboard which used to house the boiler, there is a vent covering the bottom end of the flue. Recently there has been some fluid dribbling down the wall, coming from the flue, and it solidifies into really hard yellowish glass-like residue (there isn't much - it's not leaking continuously).

I took the vent off the flue, and it is definitely coming from in there. There's a lot of rubble in there, and something which looks like the remains of an asbestos pipe??
The cupboard is warm as it has hot water pipes in it...and we had a new gas fire put in in the adjoining room (separate lined flue), a few months ago.
We only moved in 6 months ago, so don't know what else has been done to the flue.

I'd appreciate any advice - thanks!

 

[Boilerman2]

It is Rain running down the old flue picking up residues from the deposits, fit a Cowl to the top of the chimney to stop rain getting in

 

[JenniferB]

Thank you for solving our mystery!! I think the guy who fitted our new gas fire might have taken the old cowl off as the flue was out of use....and it cost us two hundred quid to get the scaffolding up there...do you think it matters if we leave it? There's not a lot coming down. I was more concerned that it was something toxic. There took the front of the vent off to look inside, and broke the sealant that was in there, so do you reckon we could just reseal it and forget about it?

 

[Burnerman]

If you leave the flue open you'll get birds in as well as the rain......its much better to put a cowl back on, or better still have it completely removed if possible.
John