Electric UFH anyone?

[Tigger]

Paul,

I used 'Enerfoil' in our kitchen and utility room as it meant we didn't have to dig up floors etc.  We just took up the old tiles, put the Enerfoil down and then laid new tiles on top.  From their sales info:

• Only 0.2mm thick - no raising of floor levels
 
• Economical to run - 80 watts per m² at 24 volts or 110 watts per m² at 28 volts

They do various sized mats (300, 400 & 600mm wide x various lengths) and ours been used on and off for the last 6 years with no problems so far (I do hope I don't regret saying that).

[offthegridandy]

Paul, 

did you finally put in the electric floor? I'm considering my options for the future with new tower/turbine and what to do with surplus.  I've been considering electric UFH to operate as a dump load.  I actually already have wet UFH fired either and or by wood or oil.  So this would be a new layer on top of a possible warm slab.

Any thoughts.

Andy

[camillitech]

Paul, 

did you finally put in the electric floor? I'm considering my options for the future with new tower/turbine and what to do with surplus.  I've been considering electric UFH to operate as a dump load.  I actually already have wet UFH fired either and or by wood or oil.  So this would be a new layer on top of a possible warm slab.

Any thoughts.

Andy

Hi Andy,

in the end we went wet and polished concrete. Having said that, I do see the merits of what you're suggesting. Could be worth doing something similar in a shed I plan to build.

Good luck, Paul

[Sean]

I've oil fired UFH, straped to 6mm mesh within a very well insulated 150mm concrete slab throughout the extension I put up as few years back - the day before the batch mixer arrived I laid another layer of mesh and straped 4 zones of loose laid electric UFH - 1Kw/2/3 & 6Kw - giving a total of 12Kw of available dump - which can be switched on/off and prioritized to suit the surplus.

I'm very glad I did this ......

[Iain]

Hi

I've been considering electric UFH to operate as a dump load.  I actually already have wet UFH fired either and or by wood or oil.  So this would be a new layer on top of a possible warm slab.

Is there not a simple way of utilising the wet system to dump the heat into the floor. Surely a simple immersion in a "container" in the wet system would work, possibly even utilising the existing pump as well. With minimal work and inconvenience.
Iain

[eabadger]

here in france they have electric central heating boilers, ones i have seen have been 3 phase, but this is common for household out here, i think if you ask for more than a 9kw supply you get 3ph.
our neighbor had wet ufh put in his new eco build with a leccy boiler, he used it first year, then got bill, hasnt used again.
but you must be able to get electric boilers in the uk? maybe an idea for any surplus pv generation.

steve

[biff]

One of my ideas,, ,
                    For using up excess lecky was to paint a few existing rads a mat black color and hang a single bar halogen fire on it facing inwards,
  I am not being funny, I have never actually tried this but I see no reason why this would not work as long as the rad had a shroud of 2k2 to trap the heat. these halogen fires come with 3 bars, a total of 1200watts. they are cheap. I
 I have bought them for less than 15 euros.The idea is to turn the rad into a kind of a low temperature boiler.
 Would it be worth a try, ?
                 Biff

[offthegridandy]

Hi all and thanks for thoughts.

Ian I plan to divert surplus power, as of now to the immersion heater but as a dump load I think I may run the danger of the stat turning the element of and still having surplus to use. I could either boil the tank or the batteries.With just PV operating just now I'm fine cos the PV just throttles back, but I will be changing the 2.4 Mtr WT to a 4mtr  unit and hence the need for a serious use for surplus. We currently have a 210 litre indirect cylinder so to use surplus to heat the floor would entail adding in a thermal store and plumbing the floor circuit into that as well.  

I have a floor area that is still just the screed I laid 15 yrs ago when I installed the wet UFH so I could do with tiling this area of floor some time as the cheap vinyl is wearing out now

It occurred to me that if I laid in either mat or cable in a number of zones, before tiling,  I could wire them with individual thermostats to operate as a series of dump loads depending on our daily supply/demand equation. Using fingers and thumbs and the back of the trad fag packet It would seem that on a capital cost basis that the electric floor would be cheaper that a TS and should be more efficient as I'd be feeding the power straight to the floor not heating water to transfer the energy. I could run this off the ac house side so relays or contactors are probably cheaper to.

Andy

[Countrypaul]

Maybe I'm missing something, but surely you would only need a thermal store if you intend to store the heat? If you intend to use it as it is produced then surely turning on the pump to circulate the hot water through your existing UFH crcuit  would incur even less captial expenditure.  If everything is within the thermal envelope all the heat would still be there regardless if you heated water to heat the slab or heated it directly, any "wastage" would just go to heat the air in the place anyway (which is what heating the slab would ultimately do anyway).

If you are producing too much power then making the house 40C through dumping into the slab might not be the best solution. You may want to consider some dump loads like Paul C. uses (I think it was he) outside undercover to lose the excess power.

EIther way you will need to ensure the floor does not get too hot for the covering so you will also need a thermostat for that, and what will happen when all the floor maxes out...

[acresswell]

 How far away is your log pile?  Can you stack the logs on scaff poles with a heating cable down the middle?  Dry your logs and a useful dump load at the same time...

I've always wanted to put a couple of heating cables/ pipes doŵn our drive, to de-ice it...

I used to have electric ufh.  Only half the floor ever get warm, so I'd certainly echo the wariness about durability.

Got an use for a bit of hydrogen?  Use an electrolysis setup as a dump load?

will you be dumping heat in summer or winter?   I'd assumed summer because the PV would be outputting more, but I wouldn't have thought you'd have wanted extra heat in the house in summer... an air con unit would have been more use!  (Tongue firmly in cheek - air con is a swear word in my dictionary!)

[Countrypaul]

  I'd assumed summer because the PV would be outputting more, but I wouldn't have thought you'd have wanted extra heat in the house in summer... an air con unit would have been more use!  (Tongue firmly in cheek - air con is a swear word in my dictionary!)

That's because you're using the wrong terminology, its not a air con unit - its called a heat pump