Open fire advice

Grenage

Good morning!

Our new place has an open fire, I know the previous occupant used it, as they had a wood store. We had it swept, and the other half was shown the brush sticking out the top of the house - all good.

I'll be installing a multifuel stove next summer, but we thought we'd use the open fire this winter for the novelty factor.

We had our first open fire last Wednesday; seemed to be ok, although it wasn't drawing amazingly well. At one point, a small amount of smoke did build up in the room. The room still smells like a bonfire.

Looking up the chimney this morning, although it goes up at 45 degrees and then straight up, I couldn't see any daylight reflected - and there doesn't seem to be a draught going up and out of the room.

I don't really know much about fireplaces, but I'm pretty sure this isn't right. Is there anything simple I am missing, before I condemn the chimney, until the stove is installed next year?

Gloomendoom

Have you tried opening a window to see if improves the draw on the fire?

If no air can get in the room, the smoke won't go up the chimney.

Grenage

I will do, but it's an old house, with some ill fitting windows and ventilated suspended floor. It seems unlikely that it wouldn't be able to pull enough air through. I'll try at the weekend.

Would you expect me to be able to see some daylight down the stack, or do you think the soot would absorb it all?

Gloomendoom

Grenage wrote: »

I will do, but it's an old house, with some ill fitting windows and ventilated suspended floor. It seems unlikely that it wouldn't be able to pull enough air through. I'll try at the weekend.

Would you expect me to be able to see some daylight down the stack, or do you think the soot would absorb it all?

Not being able to see daylight is not at all uncommon as the flue may twist and turn a bit to get around fireplaces in the rooms above etc.

I can't see daylight up my sitting room chimney.

The other thing that may be causing a problem, particularly if the fireplace isn't used much, is that the chimney just needs to warm up, otherwise the flue gasses cool down as they rise reducing the flow rate and causing a back-up.

Greenfires

If it was the first fire of the season - it could well be what's known in chimney circles as cold block - as Gloomendoom suggested. Basically a "plug" of cold air stuck in the chimney that stops things going as they should.

Try another fire using plenty of dry kindling to produce a lot of heat and flame quickly without a load of smoke. Or if you have a blowlamp handy - get that pointing up the chimney for five minutes before lighting the fire. Once the draught is established it often doesn't need to be done again unless the fire is unused for long periods and the weather is very cold.

I wouldn't be worried by not seeing daylight up the chimney - flues will often make their way around other fireplaces in rooms above so it's actually more common NOT to see light. It IS worth checking though that if the house does have other open fireplaces, that smoke isn't turning up in any other rooms. This can happen when the brickwork or mortar joints between the different flue passages ( this brickwork is known as "feathers") breaks down. You can then end up with smoke going up one warm flue, and being drawn down an adjoinng cold one rather than getting out the chimney pot.

suki1964

I find, even with a stove with a good draw, the first two fires of the season produce smoke

I need loads of kindling for those first few fires to warm the flue. After that I can get a fire lit in minutes

Grenage

Thanks for your advice, chaps. I was wondering in perhaps the fireplace itself was too large, but perhaps like you say, it's just down to it being the first fire of the year. I shall crack on this weekend with another attempt!

davemorton

And make sure you have a carbon monoxide detector or two.

Grenage

Aye, those I have.

Grenage

Success! Thanks guys; I think the main issue was the wood pieces being too large, but I opened a window a little in another room.

No smoke odour this time (other than what was there from before).

Greenfires

One other thing to remember - with an open fire many people are in the habit of clearing out the ash every day and leaving the grate clean. This is absolutely the right thing to do if you're burning coal or smokeless fuel. However - if you're burning wood, it will be a lot happier if you leave the ash to build up so it covers the grate bars. Same goes for multi fuel stoves as it happens.

Wood likes to get its combustion air from above - with a cleaned out grate it will come from below and you'll tend to blow the heart out of the fire - all the small embers will burn away to nothing and you'll be left with big charred lumps of wood sitting on the grate.

So ease off on the cleaning routine - less work and a better fire!:beer: