CH or gas fire?

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I've asked this before, but some time ago. Living room gas fire is almost unused and I'm wondering whether this winter I should make more use of it, and limit use of CH as a way to save on gas consumption?

CH heats nine radiators, in nine spaces, all but one fitted with TRV's, with a compensated controller. Gas fire is an old triple radiant type giving a choice of 3 lit or just 1, and the place is well insulated.
 
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I've asked this before, but some time ago. Living room gas fire is almost unused and I'm wondering whether this winter I should make more use of it, and limit use of CH as a way to save on gas consumption?

CH heats nine radiators, in nine spaces, all but one fitted with TRV's, with a compensated controller. Gas fire is an old triple radiant type giving a choice of 3 lit or just 1, and the place is well insulated.
What type of boiler do you have, and what output? A gas fire will be roughly 3kw, and at most about 75% efficient. A boiler could be 3-5 times the output, but be nearer 90% efficient, it will also modulate so will not be running at full power. Check your meter readings while running each on their own for about half hour and see what uses what. I would be leaning towards using the central heating, but lower the room stat a bit and run it for a shorter period.
Another thing would be to get a co alarm if using the fire.
 
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What type of boiler do you have, and what output?

Vaillant Ecofit Pure 18Kw.

Check your meter readings while running each on their own for about half hour and see what uses what.

I've considered doing that, but it seems there are just too many variables to make sense of.

It was a little chilly tonight, so fired it up and it was soon to warm on just 1/3 running.
 
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When I used to work outdoors on site jobs I would often wear a thermal vest, (either long sleeve or short depending on how cold it was), and a pair of thermal under trousers. It is amazing how warm they keep you and no one needs to know you are even wearing them!
My wife never feels the cold and walks round on bare quarry tiles in the kitchen in her bare feet. She will sit down of an evening with a thin dress on and feel quite warm even if the indoor temperature is as low as 16-17C, while I am wearing jeans, tee-shirt, jumper, socks and slippers and feeling a bit chilled. If I am going to sit down and do a jigsaw together, I will put my thermals on and am happily warm.
 
She must be relieved when you wake up in the morning and your not dead.
 
When I used to work outdoors on site jobs I would often wear a thermal vest, (either long sleeve or short depending on how cold it was), and a pair of thermal under trousers. It is amazing how warm they keep you and no one needs to know you are even wearing them!
My wife never feels the cold and walks round on bare quarry tiles in the kitchen in her bare feet. She will sit down of an evening with a thin dress on and feel quite warm even if the indoor temperature is as low as 16-17C, while I am wearing jeans, tee-shirt, jumper, socks and slippers and feeling a bit chilled. If I am going to sit down and do a jigsaw together, I will put my thermals on and am happily warm.

I love thermals.tgey are so comfortable. I'll be taking my girls down to the local camping shop to pick some for themselves.
 
Turning the heating water temperature down may help. You only get the stated efficiency when the water return temperature for re heating gets down to certain values. On your boiler that appears to be 60C. They spec 80/60 which I believe means flow 80C return 60C, However they also spec 50/30 and 40/30 where due to the way they measure it efficiency is over 100%. ;) A bit anyway.

The catch. Actual heat output from the radiator depends on both flow temperature and radiator size. Lower temperatures needs a larger radiator for the same heat output. When the system is designed they assume a temperature drop across a radiator and should set it via the lock shield valve. It's done by attaching clip on thermocouples to the flow and return pipes on the radiators. :) The gas board set my Dad's up this way eons ago. I'd hope all installers can do that now. They also curved a radiator to nicely fit under a bay window. Maybe some can still do that but times change.

The catch can be how your system was designed in the first place. 80C flow and a higher than needed return temperature may have been used. Afraid I can't remember typical numbers. 80C flow is likely to have been used as it results in a smaller radiator. Some systems early on were mostly aimed at background heating but will often cope with full or nearly so.

Thermostatic radiator valves will help anyway but may mess up condensing when lots shut off. Not sure about that, Depends what the boiler does. I'd assume it modulates power output and cycles if that is not enough. They get around the problem of having to accurately size radiators etc for the heat losses from the room. Bound to save gas.
 
Turning the heating water temperature down may help. You only get the stated efficiency when the water return temperature for re heating gets down to certain values. On your boiler that appears to be 60C. They spec 80/60 which I believe means flow 80C return 60C, However they also spec 50/30 and 40/30 where due to the way they measure it efficiency is over 100%. ;) A bit anyway.

No, that is dealt with by my compensating control system, which works very well indeed efficiency wise.

My radiators were sized for what was a poorly insulated and draughty house, so now they are over sized - which suits lower running boiler temperatures generally.

Running cost is not a problem, I am just keen to minimise my gas consumption.
 
I love thermals.tgey are so comfortable. I'll be taking my girls down to the local camping shop to pick some for themselves.
You will probably be buying foreign made ones, whilst our farmers have to throw away all the wool sheared from British sheep.
 
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