Underfloor heating

[skamuk]

I have been asked to install a power supply for approx 2m[FONT=Open Sans, arial, sans-serif]² of electric underfloor heating. I'm not installing the stuff itself but I am awaiting the delivery of it to find out the rating of it and where I need to be running cable.[/FONT]

[FONT=Open Sans, arial, sans-serif]I wanted to know if it needs some form of thermostat, or does it just run off a switched spur, switched on and off when desired?[/FONT]

[FONT=Open Sans, arial, sans-serif]This leads me to another query, surely a sensor needs to be installed in order for the thermostat to function. Or is this all incorporated in the underfloor heating mat.[/FONT]

I am not responsible for laying the stuff, nor am I the person who's ordered it or even know what it is going to look like. I have never worked with underfloor heating before. I have just been instructed to give it a supply (which in my head would be in the form of a fused (maybe switched) spur (if not a circuit of its own depending on the rating).

Some advice?

 

[telectrix]

from your mat/cable in the floor you will have the element ends, earth/cpc, and sensor cables. these should go into a stat. fed from a 3A or 5A FCU. ufh is approx. 120watts / sq.m.

 

[skamuk]

ALSO! Switched spur in bathroom... 60cm away from zone 1 ok? I understand sockets can be installed 3m away but wouldn't do it myself!

OSG doesn't make it clear...

 

[applemac]

i did one a few weeks back, i ran its own supply as it asked for max 16 amp, a probe drops down into the floor between the mat elements about 10 inches.

test mat before fit during and after, each mat should have been marked with aprox ohms

 

[telectrix]

and IR test the mat as well.

 

[skamuk]

Nice one, will let the boss know he needs a stat if he hasn't already ordered one, as I wasn't informed I would need to be wiring one! Shoudl the FCU be switched then or would the thermostat do the job?

 

[skamuk]

I can see myself doing this job as the 'know it all' tiler seems to think hes doing it (probably for the second time ever, someone told me he did it before and ordered too much mat so he ran it up the wall lol!!!) Keeps your arms warm in the shower i suppose!

 

[skamuk]

Thanks everyone. What about the spur situation? Can anyone clarify?

 

[Octopus]

Thanks everyone. What about the spur situation? Can anyone clarify?

You could google installation instuctions for underfloor heating!

 

[skamuk]

You could google installation instuctions for underfloor heating!

So simple, but just didn't think of doing it lol just done it and found the answer to all my questions...

Thanks :blush2:

 

[Octopus]

So simple, but just didn't think of doing it lol just done it and found the answer to all my questions...

Thanks :blush2:

Watch out for cheap and nasty controllers - they can be a right pain to set up. Touch screen models are far better IMHO

 

[telectrix]

your FCU is there for 2 purposes. 1. to fuse down. 2. for local isolation. for #1, an unfused FCU will do. for #2, a switched FCU will give 2 pole isolation which is preferable should a N-E fault develop in the mat. ambient do some tasty digital stats for ufh.

edit: meant unswitched, not unfused. ( well, it is only 8.00 a.m. not woke up yet )

 

[skamuk]

Thanks a lot everyone! Will get on the boss' case as I don't think the tiler is capable of fitting it correctly and more importantly safely.

See your point on the FCU teletricx. Will keep an eye out for 'ambient' stuff then.

 

[skamuk]

Hold up... Unfused fcu?

 

[telectrix]

sorry, meant to say unswitched.