This was one of the worst chimneys I had the pleasure of working on! The client was a farmer who had a tenant in this property for some time. There was a Clearview Pioneer stove sitting in the lounge fireplace. The tenant been complaining that the stove had never worked properly since it was installed. The top picture is looking down through the pot and as you can see it looks like someone has literally poured a can of bitumen down the chimney!
In fact what had happened was the tenant had been burning freshly cut timber and painted offcuts whilst telling the farmer he had burning dry seasoned timber. He also had a half pipe type cowl on the pot which are only to be installed on unused flues.
The third photo was taken of the fireplace where the stove sat. I had to get a reamer, which is a drill driven spinning chain, to blast off as much of the tar residue as I could. Once this was done (see last photo) the flue was relined and insulated. The stove was then reconnected.
Often, Jackdaws or crows try to build nests in chimneys. They will drop down a twig or two and cock their heads on one side to listen. If they can hear the twig get stuck somewhere, they will keep on dropping more twigs into the chimney until the blockage is near enough to the top for them to build a nice cosy and warm nest. Sometimes they can keep at it for years until there is quite a pile of twigs ...
With a new stove installation comes a stainless steel chimney liner. This not only adds to the safety and efficiency of the stove but twigs can't gain any purchase so they simply drop all the way down into the fire or the soot collector. No more nesting birds!
The image shows my colleague and friend Pharic with 'small nest' removed before installing a stove!
Do you have one of these cowls and are using an open fire or multifuel / wood-burning stove?
These cowls are only to be used to ventilate unused chimneys / flues. Apart from being an attractive home for nesting birds, they can cause serious problems in your chimney, such as tar build-up, cracked chimney stacks, carbon monoxide leaks, chimney fires. I have also seen cases where the stack has exploded!
If you are using one of these with a fire, it's basically like sticking a cork in an exhaust pipe!
The second image was taken looking down a seriously blocked chimney. The hole in the middle is only about one inch in diameter when it should be 8 inches!
The final picture is a view from the outside of the same chimney, you can see that the stack is cracked all the way down the side. Obviously if the customer hadn't been wise enough to call me this could have led to any of the problems described above.
The flue was completely cleaned out , the stack was re-pointed, the pot re-flaunched and an appropriate cowl was fitted.