Conservatory Heating

[Gracoli]

I have a conservatory that is about 4m square and currently has electric under floor heating. I am keen to know what is the most economical way of heating the conservatory as the under floor heating is very expensive due to the current electricity prices. Would it be a good idea to fit a new radiatior in there as part of the central heating system or purchase a storage heater or look at some other options ? Thanks

 

[Richard C]

To comply with Building Regulations any heating system in a cons. must be capable of isolation & be independently controlled from the main house system. If you decide to install a radiator in there in can be connected to the main system but, in simple terms, must be fitted with isolator valves where you tee off the main pipe runs & a TRV on the radiator itself. It’s a reasonable sized cons. & will, therefore, need a pretty large radiator to make any difference! Radiant conservatory heaters work quite well http://www.conservatoryheating.com/ & you could always consider a heat pump http://www.airconditioner.me.uk/?gclid=CMP9uOq2pJcCFQUWGgodB08xxQ Cool air in summer, use as a heater in winter. There is also a BR requirement you have an external grade door between the cons. & the main property.

By the nature of their design & construction, cons. are very heat inefficient & whatever method you use, it’s not going to be much cheaper, if any, to run! I have a 5 x 5m cons. with U/floor which works very well but we don’t use it this time of year as it’s like trying to heat the garden! Except for the odd sunny day we close it down until March.

 

[Gracoli]

Thanks Richard..Much appreciated

 

[Corgigrouch]

I would suggest a suitably sized air source heat pump.....Much cheaper than electric to run and a rapid warm up time

 

[simond]

The new Worcester IVT air/air heat pump will give very economical heating in the winter, and cooling in the summer. Ideal for a conservatory!

 

[scoobydo123]

Deffo some sort of air con with heat pump. That way you get the best of both worlds.

 

[Corgigrouch]

Always be careful how you size Heat Pumps for cooling... For heating the 6kW Worcester should be adequate, but the heat load on a South facing conservatory in the Summer is humungous and the little Worcester will struggle to provide anything other than a cooling breeze in a very hot room

 

[fender]

I totally agree with corgi.
If you can post a plan view of the room showing south, I'll do the calcs for you - it's my job.

An air to air heat pump would be fine if sized correctly and will have a cop of anything from 2-5 depending on the outside ambient. Ie, 2-5 times more efficient than normal resistive heating, so much cheaper to run.

G

 

[Richard C]

If you can post a plan view of the room showing south, I'll do the calcs for you - it's my job.

Interesting; I couldn’t find a "quick calculators" to use for any sort of cons. & didn’t really want to go to the trouble of doing heat loss calcs. so I just upped it by 50%.

If you wouldn’t mind, I would be very interested to hear your advice for a 3 sided direct, south facing cons. 4.8m x 4.6m internal with a 3.3m (max) high Edwardian roof? Cons has dwarf insulated cavity walls, Cellotex insulated slab & a 40mm thick (5 ply I think) opaque poly roof.

Apologies to the OP for the slight hijack!

 

[fender]

Hi Richard,

Even the quick calcs are not much good unless you know what you are doing and know how to enter the correct values. The final calc is only as accurate as the information entered.

I have a £750 programme that I use for these calcs, which I've never known to be wrong. I'm a bit busy tonight and tomorrow, but I'll do the calculations for you at the w/e if that's ok.

G

 

[Richard C]

Hi Richard,

Even the quick calcs are not much good unless you know what you are doing and know how to enter the correct values. The final calc is only as accurate as the information entered.

I have a £750 programme that I use for these calcs, which I've never known to be wrong. I'm a bit busy tonight and tomorrow, but I'll do the calculations for you at the w/e if that's ok.

G

Hi G. Just when you have the time would be great, no real urgency at all. Thanks in anticipation

 

[BigBurner]

Myson have specific thermostatic conservatory fan heaters off the main rad system. No need for isolation for them as when the fan is off no heat comes out.

 

[fender]

Hi Richard,

Sorry for the delay - been a bit busy.

From the given info, you would need approx 6.5kw cooling and 3.7kw heating, so if using a heat pump system, you would size as near to 6.5kw as possible, maybe round it up to 7kw. If you use an inverter system, they are a lot more economical to run than a standard system.

If you need any elaboration - give me a shout!

G.

 

[Richard C]

Thanks very much for that. I got 3.8 kw for heating so that’s as near as damn it but 6.5-7 kw for cooling is more than I would have anticipated; but I suppose extracting heat from South facing is going to be pretty demanding at times.