Electric under floor heating takes ages to warm up

[Kate Roberts]

Hi there

We moved into our house 2 years ago, with a perfect electric under floor heating system in our kitchen. Last year the thermostat started playing up - it would turn on it you flicked the on/off button really quickly, and the thermostat eventually stopped working altogether. So we had the thermostat replaced by an electrician, and since then the system has not been working properly. When we turn it on it takes hours to feel any heat through the floor, and it never heats up beyond a very low temperature.

I dont know what brand the system is because we didnt put it in ourself. The thermostat that broke was a simple on/off switch made by Wickes, there was never a timer on the system. The new thermostat is also made by Wickes, again a simple on/off switch.

If anyone has any ideas on what has gone wrong then I would be really grateful. Otherwise we are in for some cold winters!

Thanks in advance

[JimK]

can't be asimpleon/off *and* a thermostat - it would seem the control end (that you adjust etc) is not matched to the sensor in the floor (that measures the heat of the tiles etc) = were both parts of the thermostat replaced or just the control end?

Others on here may have ideas on how to go about setting it up properly (if poss)

Cheers JimK

[Ron Lowe]

We have electric UFH in our new en-suite. It does in fact have a very long heat-up / cool down cycle. That's why you need a special controller to overcome this.

Ours has a "DEVI 550" controlling it.

controller is not just a simple on/off timer. It has a temperature senson in the floor, and you set 'warm' times and 'cooler' times on the programmer. What it does is 'learn' the thermal delay over some time period. It then turns the heating up in advance, so it's warm by the time you choose. It also turns it down in advance, because the thermal inertia will keep it warm for a period of time. During the 'off' period, it's not fully off, but at a 'reduced temperature' setting.

It sounds like you don't have a proper controller installed, and the system is behaving as expected with the controlls it has.

[JimK]

Except your forgot the OP says it worked fine when they moved in 2 years ago......

JimK

[JimK]

Sorry just re-read all that - forget my last post in reply to Ron's. Cheers JimK

[newshound]

So doesn't it sound like some of the elements have gone open circuit? Out with the multimeter....

[JimK]

elementS ? isn't eleccy ufloor htg usually one long piece of cable? spose still worth a check but seems unlikely unless anything else changed besides control panel?

Cheers JimK

[Ron Lowe]

My *strong* suspicion is that somewhere along the line, a clueless electrician with no knowledge of UFH has replaced an intelligent controller with some piece of random crap.

I may be wrong, but...

[JimK]

OP is what you have shown on this webpage???:-

[Colin Wilson]

We had a TH132F (google gets you pics and prices) in our old house, and with the exception of it breaking within warranty (sounds like it was common, possibly just with one batch) it worked quite nicely and had timers for high / low / vacation etc.

Note to everyone else - basically, if the display fades / blanks, it's broke :-} (made by Honeywell, who had no issues whatsoever sending a replacement - there's a long warranty on them too IIRC)