Blocking an air vent, issues?

suki1964

grahamc2003 wrote: »

The syptoms don't point to that at all.


If you turn an extractor fan on, thenthe pressure in the hoiuse will tend to be lowered, and air will enter anywhere it can, manily from the points of least resistance. If the house is really well sealed and the chimney is the only way in, then obviously air will come in that way to replace the air being extracted by the fans.

Won't happen in my old house, even though I've been round trying to block any sources of draughts. The op obvioulsy needs a vent somewhere, probably in the room where the extractor fan is, and that would stop the air entering through the chimney. I'd also have a vent in the room where the stove is, probably near the stove to avoid draughts. The stove is probably currently getting its air from the extractor area (when it's not working), and it would offer less resistance (and therefore a better draw) with a local source of air.

Indeed it happens on the coldest of days when we have all the windows tight closed and have stuffed up draughts Opeming just one top window solves the problem - simples.


This is a very old long bar with kitchens tagged on to the end. Only the bar area is heated by an open fire and back boiler

Leif

southcoastrgi wrote: »

you can't hide in here (rather than posting your question where it should have been) hoping not to get ridiculed

Go on then, give me a good kicking ... Fortunately I am not blocking a vent that is required by the fire, although it does look like it can serve a purpose.

Leif

Swipe wrote: »

Get a vent cover that slides open and shut, then just open the vent when you use the stove and extractor fan..

Thanks. Do you know a source for a vent with flaps? The existing vent consists of a plastic tube about 12cm outside diameter through the full width of the wall, a grill on the inside, and a right angle cover on the outside. I have not seen any inside covers with flaps.

reeac wrote: »

I'm not familiar with the Charnwood C-4 but assume that it's a regular wood burning stove in which case it will need a supply of air as did the open fire. Are you assuming that being only 5kW ita air requirements are too small to need a vent? Our Clearview 5 kW stove has an underfloor air vent which was constructed when the bungalow was built which is the ideal way to do it but in an existing house it's all more difficult. Is there an external wall adjacent to the stove? Is it possible to box in an air duct from the present air supply?

It is a wood burning stove, 4.9kW, so exempt from the need for a vent assuming an adequate supply of air. There is no problem when the vent is closed, except when the extractor fan is on. Hence I do not run them together. Not the ideal solution.

Having just checked my CO alarm, I noticed the power light is not on. It does sound when the test button is pressed, so perhaps time for a second one just in case.

Swipe

Leif wrote: »

Thanks. Do you know a source for a vent with flaps?

Try this:

http://www.inbrass.co.uk/acatalog/Closeable_vents.html

or

http://www.screwfix.com/p/map-vent-adjustable-vent-silver-152mm-x-229mm/67350

reeac

I'd still like to know the position of the vent with respect to the stove - if it's very close then the drawn-in cold air won't matter, if it's some way away but on the same wall then an extension duct from vent to stove might be acceptable. If it's across the other side of the room then you've got a problem unless the room has a suspended wooden floor. Come to think of it if that's the case then an underfloor draught would be easy to arrange.

Leif

Swipe wrote: »

Try this:

http://www.inbrass.co.uk/acatalog/Closeable_vents.html

or

http://www.screwfix.com/p/map-vent-adjustable-vent-silver-152mm-x-229mm/67350

Thanks for posting links, but sadly what I am looking for slips over a pipe. I'd rather not screw it into the wall. The one I have has a fixed grill, and I've not seen similar ones that can be closed. .

Leif

reeac wrote: »

Our Clearview 5 kW stove has an underfloor air vent which was constructed when the bungalow was built which is the ideal way to do it but in an existing house it's all more difficult. Is there an external wall adjacent to the stove? Is it possible to box in an air duct from the present air supply?

The C-4 can use a rear vent to take in air from outside via a hole in the wall. But mine is in a fire place in an internal wall. Taking air from outside makes the stove more efficient, of course, as it means it is not sucking warm air out of the room and up the flue.

muckybutt

We have a similar problem with the two room where we have solid fuelled fires one room being the stove the other being the range, problem being if the kitchen extractor is on before we light either fire then we get smoked ! even in the living room where the stove is which is the other side of the house....and that has a vent in the wall for the stove.

Cant say it causes a big problem, we just either have to shut the connecting doors when lighting the fires or turn the extractor off, once the fires are going theres no problem at all because they draw better than the extractor.

southcoastrgi

grahamc2003 wrote: »

The syptoms don't point to that at all.

The op obvioulsy needs a vent somewhere, probably in the room where the extractor fan is, and that would stop the air entering through the chimney.

Ummmmmmm so which is it, how can you say it doesn't point to that then say they obv need a vent, make your mind up.

ventilation for either gas or solid fuel must be calculated on worst case, ie if you switch an extractor on & smoke comes into the room then there isn't enough permenent ventilation so you need more, opening a window isn't good enough, don't forget it's not just smoke coming in it's co as well & that can & will kill you.

grahamc2003

southcoastrgi wrote: »

Ummmmmmm so which is it, how can you say it doesn't point to that then say they obv need a vent, make your mind up.

ventilation for either gas or solid fuel must be calculated on worst case, ie if you switch an extractor on & smoke comes into the room then there isn't enough permenent ventilation so you need more, opening a window isn't good enough, don't forget it's not just smoke coming in it's co as well & that can & will kill you.

Are you for real?

You said it was clearly a problem with the fire.

Quote
then you need to get this sorted ASAP as there is clearly a prob with the fire before someone dies, opening a window is not the answer

I said it didn't look like a problem with the fire to me, looks like a ventilation problem.

And then you post the above!