Problems with wood-burning stove

[NormanH]

A friend of mine has just bought a new Poêle à Bois and had it fitted by the shop. It is a Supra Vosges

Ordered in October it was delivered last week.

She has already had to ask the fitters to come back because they fitted the joint  between the flue and the Poêle incorrectly.

She had had a new chimney and flue built for it, but is having several problems.

1) A build -up of tarry deposit on the out side of the flue

2) Inadequate 'play' in the regulator

3) High wood consumptuion

4) It will not stay in at nght...

This is not her first experience with a wood burner. She had one previously in Scotland.

Can anyone offer any practical advice, and does anyone know if she can get her money back if it continues to be unsatisfactory?

[clarksinfrance]

1 If tar is showing on the outside of the tubes then they have been fitted incorrectly, and joint should have the female end (socket) pointing towards the sky, so that when condensates trickle down the inside of the tubes (as they will undoubtedly do) they stay inside.

2 More info needed about the "regulator" is it on the burner or is it installed in the flue?

3 High wood consumption is indicative of air passing through the burner with a greater than necessary force, 2 main causes I have come across are:A) flue size has been reduced from exhaust size of burner, if this is what is happening in your friends case, then as a matter of extreme urgency she needs to get the installers back and have the correct diameter flue fitted. B) Joints in the burner have not been sealed properly at the manufacturing stage. There are some other causes.

4 Very few fires are designed to stay alight all night if burning wood. If hers is designed to achieve this, then same answer as 3 above. It can be quite damaging to an installation to try to keep a fire in all night, as the temp inside fire and flue is reduced, leading to a greater build-up of condensates in the flue liner and the burner itself.

Having just looked at the Supra website, it doesn't appear that the Vosges is designed to stay alight all night. I doubt she will get her money back for the stove as it is almost certainly working correctly, more likely to get better results ensuring the installation is correct and complys with French Normes and European Normes.

Please keep us informed of the outcome.

[NormanH]

Thanks for your helpful reply

I have forwarded it to her, and will be in contact later this week to see what she has decided to do

[LesFlamands]

This stove is not designed to stay in overnight or even burn at a low rate. The ash drawer is just another air leak and whilst I've not looked at this particular model closely most Supra stoves only make a token effort at sealing the doors.

There are basically two types of wood stove: the first type is just a metal box to burn wood in with no ability to control the burn rate or heat output, this applies to most French stoves under 1000 euros. The second type are properly designed stoves which allow the burn rate to be regulated virtually down to zero and they are also design to give an almost even heat output over a burn cycle (usually 4 to 8 hours).

With regards to the installation if there is tar on the outside of the flue pipes this indicates that the pipes have been installed in the wrong direction. This is often another problem with french stoves where the flue spigot on the stove will only accept the female end of the flue pipe when in fact it should be the male end so that any condensation forming in the flue run back into the stove

[NormanH]

Thanks again.

I am forwarding these useful tips to her.

[JohnRoss]

Hi having been looking at our Supra installation re the female end of the flue pipes pointing towards the sky. The T piece at the back of the stove and the bottom of the flue has the male end pointing upwards and the bottom end has the large clip and blanking plate fitted and cannot go the other way up. Likewise the next section up with the rotating choke type plate has the female end pointing down onto the male end of the T piece. The length of overlap seems to vary between 5 and 6 cms. There is a section further up with a female end at both ends i.e. up and down. There is no sign of stuff running out of these joints and they seem to be a tight fit and did not come apart when I had to remove them from the bottom of the flexible conduit to sweep the chimney. Maybe it makes a difference if top exit rather than back exit is used or maybe the OP's friend had a distorted section in the installation of the flue?...........................JR