heat lost through a flue

Nicolai1977

Hi all. My wife and I have just bought a new house, but it comes with an open flue gas fire fueled by LPG (no mains gas available). My thoughts are that this is horrifically inefficient and will cost us a fortune in lost heat even if we never turn it on due to the warm air from the house going straight up the chimney. Does anyone have a rule of thumb on how much heat is lost through an open chimney. I have already said to the developer will they disconnect the LPG at the ring main, but would it help if I removed this fire and installed a high efficiency one that doesn't have an open flue but still use the LPG.

The planning permission energy assessment had a limit of 7m3/m/m2 which I would say is improbable with an open flue fire.

The planning permission also had 30% energy efficient light bulbs, I counted 3 out of about 20 light fittings so I have already said I expect it to meet the planning permission requirements... One of the light fittings is straight out of my bug gypsy wedding anyway so that will need to go regardless... Thanks for any advice.

diywhynot

Take it out and don't replace. A gas fire isn't very mse, especially one fuelled by LPG

What is the source of heating in your new home?

Nicolai1977

Thanks for the reply, I certainly didn't think it was a great idea. Heating is also LPG unfortunately, but that's the downside of a house in the countryside. I can cope with the boiler being LPG, but an open flue fire just seems a stupid thing to install in this day and age. Energy regs need to be updated immediately, to stop aesthetics getting in the way of reality.

diywhynot

Nicolai1977 wrote: »

Thanks for the reply, I certainly didn't think it was a great idea. Heating is also LPG unfortunately, but that's the downside of a house in the countryside. I can cope with the boiler being LPG, but an open flue fire just seems a stupid thing to install in this day and age. Energy regs need to be updated immediately, to stop aesthetics getting in the way of reality.

Bizarre, isn't it? Style over substance.

Ben84

diywhynot wrote: »

Take it out and don't replace. A gas fire isn't very mse, especially one fuelled by LPG

What is the source of heating in your new home?

Gas fires can be a very efficient way to heat one or two rooms - giving an alternative to central heating the whole house. However, can is the important word. Decorative gas fires aren't a lot of use for anything other than looking nice due to their poor efficiency ratings.

Still, they look attractive and are good for the value of the house. This is why the developer installed it, so I might be tempted to keep it if I didn't find it ugly as it will likely make the house more attractive if you ever sell it.

southcoastrgi

i agree with ben84 most gas fires are a focal point & people like to see a roaring fire it all adds to the re-sale value, nearly all fires that are installed in chimney breasts are open flued even the ones that sit on front, so yes i would keep it connected & only use it when you want a nice romantic eve in front of the fire, after all if you don't use it it's not costing anything in LPG

Gloomendoom

Nicolai1977 wrote: »

Thanks for the reply, I certainly didn't think it was a great idea. Heating is also LPG unfortunately, but that's the downside of a house in the countryside. I can cope with the boiler being LPG, but an open flue fire just seems a stupid thing to install in this day and age. Energy regs need to be updated immediately, to stop aesthetics getting in the way of reality.

If you feel so strongly about it, just don't turn it on. You have central heating after all.

If you fit a stove without a flue, where do you think all the exhaust gasses are going to go?

Jonesya

If you can live with the fire having a glass front, you can get coal/flame effect fires with efficiencies approaching 90%.

That's not far off a condensing gas boiler so certainly not wasteful by any means, if used heavily or as a a primary source of heat then they're far cheaper than electric heating.

Nicolai1977

What worries me is the additional draught an open flue creates, i.e. you get the chimney effect all of the time. I'm pained to pay to heat the air in the house and for it to go up the chimney and be replaced by cold air from outside. I'll do some calcs and work out the air flow through the chimney.

I can get the value side of it, people like the fire. I just hate the thought of paying for heat for it to be wasted.

I do struggle with the efficiency aspect with domestic fires. To get 90% efficiency you need a flue gas temperature less than 230degC and excess combustion oxygen of about 3%. Can't see how that is controlled in a fire.

Gloomendoom

Nicolai1977 wrote: »

What worries me is the additional draught an open flue creates, i.e. you get the chimney effect all of the time. I'm pained to pay to heat the air in the house and for it to go up the chimney and be replaced by cold air from outside. I'll do some calcs and work out the air flow through the chimney.

I can get the value side of it, people like the fire. I just hate the thought of paying for heat for it to be wasted.

I do struggle with the efficiency aspect with domestic fires. To get 90% efficiency you need a flue gas temperature less than 230degC and excess combustion oxygen of about 3%. Can't see how that is controlled in a fire.

If you don't like it, don't use it. Get a nice electric fire instead.

Avoriaz

Nicolai1977 wrote: »

What worries me is the additional draught an open flue creates, i.e. you get the chimney effect all of the time. I'm pained to pay to heat the air in the house and for it to go up the chimney and be replaced by cold air from outside. I'll do some calcs and work out the air flow through the chimney.

You need some ventilation in a house.

Last year we moved to an 8 year old house. It has a coal effect gas fire with a chimney. In the winter we don't notice any draft when the fire is not in use. It is very useful to quickly heat up the living room when we don't want the whole central heating on.

I suspect that you are worrying unnecessarily.