Type of heating for conservatory conversion?

vigman

We are having a conservatory converted to a warm flat roof construction with a 2x1 m roof light.

It can't be connected to the main central heating system, so I'm wondering what type of heating would be effective and as cheap as possible to run please? The room measures 3m x 4.5m floor dimension and about 2.5m tall.

I've looked at electric clay filled radiators and oil filled radiators as well as infra red heaters.

The room will be used for dining and TV use in the winter months and possibly even a spare bedroom.

Any thoughts welcomed please?

TIA

Neil_Jones

All electric is 100% effective, so you have it on for 1 hr at 1000w output then it will output 1000w of heat over one hour at a cost of one electric unit rate (anywhere from 14p upwards).

There is no difference between the various types of electric radiators, whether you buy fan, oil, convector or whether its powered by squirrels, they all cost the same to run.

Sea_Shell

Will you be able to close off your new room to the rest of the house when not in use?  Or is it fully open plan?

QrizB

vigman said:

Any thoughts welcomed please?

Air-to-air heat pump? More expensive to install but much cheaper to run than any of your other options?

wittynamegoeshere

Neil_Jones said:

All electric is 100% effective, so you have it on for 1 hr at 1000w output then it will output 1000w of heat over one hour at a cost of one electric unit rate (anywhere from 14p upwards).

There is no difference between the various types of electric radiators, whether you buy fan, oil, convector or whether its powered by squirrels, they all cost the same to run.

True, but arguably Infra-Red can give a greater feeling of warmth than the other options, for a given air temperature.

We've got one and it's lovely, it's like sitting in the sun.  You can feel the infra-red heat on your skin, which makes you feel warmer than you otherwise would at the same air temperature.

However, they're only better if they are pointing directly at people.  Ironically this often means that they're mounted high up which means that the radiant heat that they also emit can basically go up and through the windows and that lovely new skylight without the people below ever encountering it.

If you can get one in the sort of position that a fireplace would be, i.e. low down and pointing at people, then they're excellent.  The IR will warm your skin while the radiant/convected heat will warm the room.  The downside is that this will be a hazard to children, pets, long flowing clothes etc, so it may not be an option.

There's no need to spend a fortune on the fancy gimmicky ones, they're no better than any other.  This is the one we have...

https://www.screwfix.com/p/mh-7-1-freestanding-quartz-heater-1000w/7748p

It's a bit cheap looking but does the job absolutely perfectly.

But, in general, heating a room that has lots of windows will be expensive.  Double glazed or not and however modern they let out much more heat than a wall.  Electric costs around 3-4 times more than gas for starters, heating this room with electricity may well cost the same as heating the rest of the entire house.

An air-to-air heat pump could be a good option, especially as it will give you the option of cooling the room in the summer too.

matelodave

There you go - https://www.cooleasy.co.uk/3-5kw-12000btu-inverter-srk35zmp-w.html quite a bit more than an oil filled rad from Argos or B^Q and I guess a lot less than a magic clay, fairy dust, mermaids oil device from Fischer etc. But it will use about a quarter of the leccy than any of them and you can use it for cooling in the summer

wittynamegoeshere

...with the obvious downside of creating some noise while in use.  The outdoor unit will be noisier than the indoor one, there may be restrictions on how close to a boundary it can go.

vigman

Neil_Jones said:

All electric is 100% effective, so you have it on for 1 hr at 1000w output then it will output 1000w of heat over one hour at a cost of one electric unit rate (anywhere from 14p upwards).

There is no difference between the various types of electric radiators, whether you buy fan, oil, convector or whether its powered by squirrels, they all cost the same to run.

Thanks. I do realise you only get the same' bang for your buck' however using say, a fan heater gives heat that only lasts whilst its on. Using a heat retaining radiator, surely continues to disperse heat, albeit increasingly less, over a longer period when it is not powered on?

vigman

Sea_Shell said:

Will you be able to close off your new room to the rest of the house when not in use?  Or is it fully open plan?

Yes, the room can be isolated.

matelodave

vigman said:

Neil_Jones said:

All electric is 100% effective, so you have it on for 1 hr at 1000w output then it will output 1000w of heat over one hour at a cost of one electric unit rate (anywhere from 14p upwards).

There is no difference between the various types of electric radiators, whether you buy fan, oil, convector or whether its powered by squirrels, they all cost the same to run.

Thanks. I do realise you only get the same' bang for your buck' however using say, a fan heater gives heat that only lasts whilst its on. Using a heat retaining radiator, surely continues to disperse heat, albeit increasingly less, over a longer period when it is not powered on?

Yes, but it takes time to get up to temperature as well.

You dont actually gain anything you just shift the period of producing useable heat from half an hour to after you swicth it on to half an hour after it's switched off. The only practical sort of heat retaining heater is a proper storage heater that uses off peak leccy. Fischer, Rointe and any other heater filled with exotoc materials ARE NOT STORAGE HEATERS they just take longer to warm up and to cool down than a fan or convector heater.

If you are thinking of going down that route then one of these will do the same job for a lot less upfront money and will use exactly the same amount of energy for the same amount of heater as an oversold very expensive one. - https://www.diy.com/departments/electric-2000w-off-white-oil-filled-radiator/1394606_BQ.prd?storeId=

Neil_Jones

vigman said:

Neil_Jones said:

All electric is 100% effective, so you have it on for 1 hr at 1000w output then it will output 1000w of heat over one hour at a cost of one electric unit rate (anywhere from 14p upwards).

There is no difference between the various types of electric radiators, whether you buy fan, oil, convector or whether its powered by squirrels, they all cost the same to run.

Thanks. I do realise you only get the same' bang for your buck' however using say, a fan heater gives heat that only lasts whilst its on. Using a heat retaining radiator, surely continues to disperse heat, albeit increasingly less, over a longer period when it is not powered on?

Well if it continues to disperse heat it won't be dispersing very much, considering the bulk of of the run of the mill models will simply heat the air around it.  Physics means said air will rise, spread out, cool and fall back down again.

There are hear retention radiators available, ie https://www.electric-heatingcompany.co.uk/electric-radiators/heat-retention-electric-radiators/ for example, but tthese appear to be based on the same principle as Economy 7 Storage Heaters - in other words as well as kicking out heat themselves, it gets transferred to a heat retaining "brick" if you like.  So they still have to be run to "charge" these up, but how much heat they hold and kick out after a charge I suppose depends.  They'll only last as long as the brick can hold the heat.