cheaper option: calor heater or central heating?

Zziggi

hello,

My husband feels the cold and needs heating on during the day and stays in one room. I'm trying to work out my best option for heating during the day. I could (a) have the central heating on all day or (b) use our calor gas heater. How would I work out which is cheaper (other than seeing how long a canister lasts). The heater has a 15kg canister (£25.99 per refil) and we have it on 1 bar out of 3 (I.e. 1/3 power). I could work out central heating cost but I can't work out comparable cost without seeing how long a canister lasts us.

As a rule of thumb, does anyone know if the calor heater would be cheaper.

Thanks in advance - hope I've made sense!

mech_2

From Calor's website:
How many hours of heat are provided by a 15kg cylinder?

Running constantly at 3kW, a 15kg cylinder would last for around 68.5 hours.

So, 68.5 hours times 3kW is 205.5kWh. 2599 pence divided by 205.5kWh is 12.65 p/kWh. Even an electric heater on daytime electricity could compete on cost at that rate.

You don't say what fuel you use for central heating. Most homes in the UK use mains gas, which is probably not far off 4p/kWh. The running cost will depend on how efficient the central heating is relative to the Calor heater.

Unless you have quite a new boiler it's probably around 65% efficient. Based on that assumption, the useful heat from gas central heating might cost more like 6.15p per kWh. Still twice as much heat for your money. It might be worth turning all the radiators off in other rooms during the day and using the central heating to heat that one room if you have mains gas.

Zziggi

Thank you mech you're a gem!

My mind was getting boggled with KW and KWh conversions. Fortunately we have a new boiler so it is fairly efficient, but, as you say, even if it is only 65% efficient - the costs are clear.

Central heating on, upstairs radiators off

Thanks Mech

P.S. would it cause any problems/increased chances of a leak if i turn radiators off (by turning the thermostat valve) during the day then turn them back on at night?

mech_2

Zziggi wrote: »

P.S. would it cause any problems/increased chances of a leak if i turn radiators off (by turning the thermostat valve) during the day then turn them back on at night?

No, in fact it might be good for them as it could prevent ones that stay on most of the time from seizing. When you turn the top of a thermostatic radiator valve to turn it up/down/off it just moves the thermostatic mechanism further or closer to the actual valve that stops and starts the water. That valve is designed to cope with being switched on and off all the time as that's how the thermostat regulates the room temperature when the radiator is on anyway.