GCH vs fan heater

Pmarmalade

I realise this must get asked a lot and there are many variables, but hoping for even an educated guestimate

Stats:

• 2-level, 3 bed ex-council house
• Double glazing, loft insulation, neighbour reckons wall cavity insulation present and appears there are signs of it, but not 100% convinced due to house loosing heat quickly
• GCH - 4 standard-sized rads + small bathroom rad; 5-year-old basic boiler
• Cheapest dual-tariff via Cheap Energy Club

I live alone and tend to use one room exclusively most of the night. I use a 2kW fan heater on a thermostat kept at a modest setting. I heat up the bedroom with it just before bed then switch it off for the night.

Is it likely cheaper for me just to heat a single room vs the whole house via GCH?

Another concern is pipes freezing. With no GCH on, the rest of the house ranges between 8C-10C with outside temps -2C/-3C just now. Do I need to worry about outside/underfloor pipes freezing?

Robwiz

The only surefire way to answer your question is by trying both and discovering which is best.

If you take daily gas and electricity meter readings and alternate between the two heating methods your readings will show which is best. You'd need to close the radiator valves on all except the room you want to heat.

However, my hunch is that provided you are using the fan heater for a short time only then it will cost less than gas (which has to warm up all the water in your system from 8º C before it has any heating effect and it takes less energy to heat air than water.

As an aside, many people who don't use central heating find that electric blankets are an effective alternative to room heating.

Cardew

Pmarmalade wrote: »

I
Is it likely cheaper for me just to heat a single room vs the whole house via GCH?

Instead of having the CH off, why don't you just heat one room with CH i.e. switch off all the other radiators?

stator

You'll have to try it and see, taking meter readings. But I would think gas central heating is cheaper, if you balance the radiators to heavily favour the room you live in.

saveallmymoney

Do you have thermostatic valves on the radiators?

McKneff

Why do you need to heat the bedroom up before you go into it. You are heating it up for the sake of a few seconds between going through the door and getting into bed.


Just get into bed, you will be warm within minutes.


Im a pensioner but I would hate to be in the position where I am penny pinching to allow myself to be warm.


Or are you just tight

bsod

the cheapest way of heating the bedroom will be the fan heater on for 10-15 minutes before bed, along with a hot water bottle and second quilt - little cost, lots of comfort. 15 minutes heat + kettle boil for hw bottle is about 6 or 7 pence, second quilt about £6-8.

As for heating the whole house for a day, it depends on insulation, room size etc, but it's probably still cheaper to use a fan heater in one room than heat the whole house or even a portion of it using CH. My CH is currently costing 72p per hour, that may go down to 45p per hour once the thermostats kick in, but it will take pounds to get there. A 2kw fan heater will average under 22p/hour.

A compromise would be to set the CH to a lowish temp during waking hours, eg 10-12C, which will take the chill out of the house, and avoid frozen pipes, and topup the room you use most - a gas fire in that room would be an even cheaper solution, if possible.

to answer it properly, try the alternatives, and take meter readings

keicar

Trial and error! Electricity is easy to work out, your 2kw fan heater will cost approx 26p per hour to run continually.

Gas is a little more difficult, best way is to turn all your gas appliances off (cooker water etc) take a meter reading, then run the gas CH with thermostat right up for an hour and then re-read the meter. Deduct the original reading and assuming you have a standard type gas meter multiply the difference by 11, that will tell you how many gas kw/h's you've used, multiply that by 5p* that will be the approx cost per hour of your gas CH.

* 5p is an approx average cost of a gas kw/h today, maybe a little on the generous side.

Don't forget to turn your thermostat back down!

My 3 bed semi costs approx 50p an hour to continually run the gas CH.

st999

why don't you just heat one room

A couple of years ago my heating broke down in the middle of winter and was off for 3 days.

I had a fan heater heating the lounge and left the upstairs unheated.

It was like living in the dark ages. Every door had to be kept closed and the cold draught when a door was opened horrifying.

It got so bad we left our gas oven on with the door open.

As for the bed it felt cold and damp, we don't have an electric blanket.

We hated getting up in the morning even our clothes felt damp.

Nowadays, and before, the whole house is heated to 21 deg C during the day and 18 deg C during the night and all the doors can be left open.

Not a draught anywhere.

stator

Don't use a gas oven for heating, they aren't vented

Pmarmalade

Thank you all for the helpful responses!

Good suggestion on the electric blanket - that's a go-er for sure!

My boiler efficiency rating is ~90%, had anticipated less. Frustrating that I don't have a thermostat control, though, just dials on boiler for water and rad temp; might look into having one retrofitted.

Gas is 3.5p/kWh while elec is 10.7p/kWh - I knew gas was cheaper but I didn't realise it was as little as 1/3! Looks like the GCH is around 35p/hr (with radiator not in use off). I'll continue to heat the house for an hour in the mornings, again for me coming home from work and then again an hour or two before bed and top up with the electric heater in between if needed in the room I'm in.

I've found a happy medium in the 'office' with the fan heater set at half power (1kW according to socket power meter) and almost constantly on, so that's simple to calculate. In the living room it's a convection heater (so no noise drowning out TV) but it's a bigger room and draughty so 2kW needed, est. about 75% on time with thermostat so 16p/hr.

That's only going to be £40-£45 a month in heating during the worst months.

The rad in the spare room was turned off as it's always empty, but turning heaters on/off in other rooms constantly always seemed a big hassle. However, I guess it's just a case of getting into the habit of it and thinking ahead. I can't turn hall, master BR or bathroom off, but at least I can turn the living room or the 'home office' rad off depending on which room I'm using that night (90% of my evening awake time is in either one of the other).