Chimney blowing smoke back when slightly windy

Wee_Bargain_Hunter

Sorry, can't see spec and not sure which fire.
He says this problem can occur in a detached house when the house door is at the opposite side of the house from the wind direction, thus causing a vacuum, esp when there's a strong wind. There's no easy remedy.

maypole

This used to happen to us when there was a southerly wind, what a mess it used to make. We ended up getting a gas fire because of this, but I do miss the coal fire and I am tempted sometimes to try again with one.

pboae

Razor wrote: »

If the problem clears when you open a window you have insufficient ventilation not a problem with downdraft, it sounds like thermal inversion to me, if this was a gas appliance I would make it safe til the problem was rectified, the flue gases from an open fire can kill you as quick as a gas appliance.

I am not qualified in solid fuel fires but would suggest you not use it until you have consulted a HETAS engineer

As Razor says if opening a window helps it sounds very much like a ventilation issue not a downdraft. In which case you will have carbon monoxide coming in as well. Worst case scenario you may have carbon monoxide coming in even when it's not bad enough for you to see the actual smoke.

It's not worth taking chances with it.

Wee_Bargain_Hunter

Without seeing your house, from what my sweep told me yesterday, a cowl is unlikely to help. It's not the wind blowing *down* the chimney that's the problem. It's the wind that's being *sucked* into the house via the chimney because of the wind direction (from north) and door location (south) creating a vacuum. Alternatively, maybe you have an open window on the south, or else an incorrectly installed under-floor draught system with a Baxi fire ie with a sunken ash pan.

One final thing is that there could be a piece missing/ broken off the northern side of your chimney pot. Maybe you could have a look at that first before spending money?