Chimney blowing smoke back when slightly windy

WelshLamb

Hi there wondering if anyone can help.

We've got an open fireplace in our new house (never used to be used for an open fire but it's clear.) The only trouble is as they chimney isn't very high, when the wind blows from a certain direction we can't have an open fire as the smoke blows back in the house!!! uuckk, making a mess!!
(but if we open the window a little the smoke sucks upwards propertly, but that isn't the point!)
I was thinking of going to the builder centre to ask for something but was wondering if anyone can point my in the right direction..is there such a thing that can be placed on top of the chimey to distract the wind as it were.

thanks

moonrakerz

A cowl on the top of the chimney might help but it could be the shape of the fireplace itself.
I had a similar problem which I solved by putting in a pre-cast shaped backing into my fireplace which improved the airflow - all the smoke then went UP the chimney !

HugoSP

Also, check the flu diameter. Certain Diameters are only good for solid fuel burners.

Coolhandluke

You will probley end up having to buy a cowl costing around £50 :eek: although some can go up as far as £100:eek:

WelshLamb

Coolhandluke wrote: »

You will probley end up having to buy a cowl costing around £50 :eek: although some can go up as far as £100:eek:

thanks for the advice, what exactly does a "cowl" do?:o

Razor

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

Ephemera

....Or ask your local chimney sweep for advice, if they are suitably qualified.

WelshLamb

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

really? wouldn't that be the case no matter which way the wind was blowing? it only seems to happen when it's windy and northanly wind. thanks

Wee_Bargain_Hunter

I'm told by my local sweep that he needs more info. What type of fire is it? Is there an under floor draught system? Is it a Baxi fire? Do any outside doors face south?

Razor

It is not possible to determine high/low pressure zones around a property without much more information and preferably a site visit, when it is safety related I would get a pro in. Some things are not worth taking the chance over.

WelshLamb

Wee_Bargain_Hunter wrote: »

I'm told by my local sweep that he needs more info. What type of fire is it? Is there an under floor draught system? Is it a Baxi fire? Do any outside doors face south?

http://www.stovax.com/products.htm?cid=5&sid=16&pid=172 this is the fireplace.
Really interesting reading your replies and will have to get it checked out incase, but it seems to me that wind gets down the chimey at certain times. Some nights there's no problem but if you can hear the wind outside, I have to test to see if the smoke is getting sucked up witha figherlighter and a little coal before starting it properly. If it's seriously windy there's no point in bothering!
Someone did suggest a "wind jammer" as they also thought that it was the wind getting in or rising the chimney high (which I wouldn't bother with the cost!!)