Electric Boilers vs Electric Heaters

EnglishMohican

12kw is 12kw whether it is used in a boiler or as 6 x 2kw radiators. So superficially, there is no difference in cost for the same heat output and nominally they produce the same heat out.

Then the subtleties creep in. An oil filled radiator in the lounge is putting all of its 2kw into the lounge. That is a simple fact. If you have a water based central heating system with only the radiator in the lounge turned on then you will use slightly more than 2kw at the boiler to put 2kw into the lounge because some heat will be "lost" on the way to the lounge. Therefore in this somewhat strange circumstance, the boiler will cost more for the same result.

The problem with the previous paragraph is that the "lost" heat may not be totally lost. It may be heating (just a bit) your kitchen or dining room or whatever rooms the pipes pass through. Which could be good or bad.

Using just one radiator is probably an extreme case. If you had four radiators on, the losses would be proportionataly less depending on the exact plumbing arrangement.

I already have gas fired central heating but if I could ignore the huge cost advantages of gas, I would not install water filled radiators ever. Your oil filled radiators can be put where you want them and moved when you want. I suppose they can leak but my water filled ones are much more likely to leak and require much more maintenance.

Central heating is hard to control. I want two bedrooms (unused) cool all the time and the two used ones warm in the morning and cool the rest of the day and night. I want the lounge warmer in the evening than during the day and off altogether if I am out. Organising a system that can do that is possible in theory but hard in practice. You already have a system that can do that much more easily.

The pipes running round the house are not pretty and the radiators limit where you can put your furniture.

By all means look at oil and Economy 7 (not all its cracked up to be in my experience) and Solar power etc but please do not replace your existing system with an electric boiler and wet radiators. A situation in which it would make sense is incredibly rare.

Cardew

Agree with the sentiments above - a electric boiler supplying hot water to radiators is the very worst solution.

oysterpearl

EnglishMohican wrote: »

12kw is 12kw whether it is used in a boiler or as 6 x 2kw radiators. So superficially, there is no difference in cost for the same heat output and nominally they produce the same heat out.

Then the subtleties creep in. An oil filled radiator in the lounge is putting all of its 2kw into the lounge. That is a simple fact. If you have a water based central heating system with only the radiator in the lounge turned on then you will use slightly more than 2kw at the boiler to put 2kw into the lounge because some heat will be "lost" on the way to the lounge. Therefore in this somewhat strange circumstance, the boiler will cost more for the same result.

The problem with the previous paragraph is that the "lost" heat may not be totally lost. It may be heating (just a bit) your kitchen or dining room or whatever rooms the pipes pass through. Which could be good or bad.

Using just one radiator is probably an extreme case. If you had four radiators on, the losses would be proportionataly less depending on the exact plumbing arrangement.

I already have gas fired central heating but if I could ignore the huge cost advantages of gas, I would not install water filled radiators ever. Your oil filled radiators can be put where you want them and moved when you want. I suppose they can leak but my water filled ones are much more likely to leak and require much more maintenance.

Central heating is hard to control. I want two bedrooms (unused) cool all the time and the two used ones warm in the morning and cool the rest of the day and night. I want the lounge warmer in the evening than during the day and off altogether if I am out. Organising a system that can do that is possible in theory but hard in practice. You already have a system that can do that much more easily.

The pipes running round the house are not pretty and the radiators limit where you can put your furniture.

By all means look at oil and Economy 7 (not all its cracked up to be in my experience) and Solar power etc but please do not replace your existing system with an electric boiler and wet radiators. A situation in which it would make sense is incredibly rare.

Thank you for such a good reply. It looks like asking the question on here has saved us a lot of money that we would have otherwise wasted!