Installing underfloor heating (warmup under wood panels) with contactor

[Simoniz]

Hi
just want to ask
i been instaling heating mats before, but now I need to install 3 mats for large kitchen/ dining,
total 36 square meters of mats, each mat have 1680 Watts, and this need to be 1 zone - on one thermostat, maximum I can connect to thermostat is 3600Watts, We run separate cable from fusebox to fused spur switch then thermostat. Do you know how to connect this? We should use a contactor?
where contactor should be placed? What kind of contactor? Connect each end of matts to spur switch then to contactor and then thermostat?

Thanks
Simon

 

[SparkyJoe]

You Just need a contactor thats thats rated above your load. Personally you want all the gear out of sight apart from the thermostat. sounds like you need a electrician tbh.

 

[R G]

Hi
Best way is to install the contactor near the D/B controlled by its own 20amp RCBO, (3600W total load ) so fused spur is no good . The stat wire run back to here protected by a 3 amp fused spur , all feeds to heating mats fed via contactor .
All work is notifiable , so Electrician required

 

[R G]

Re Above
3 x 1680W , = 5040 W total load , so 32a mcb required and 6mm feed to contactor

 

[Simoniz]

Re Above
3 x 1680W , = 5040 W total load , so 32a mcb required and 6mm feed to contactor

thanks guys.

I run 2.5 mm cable, so its wrong, i need 6mm. Cant be 2.5?

what contactor to buy?

 

[Simoniz]

Can i do it myself and ask an electrician to come and check? And sign certificate?

 

[R G]

If I were you I would run all the cables back to the mains position , ie the feeds from the underfloor heating and back from the stat , and then contact a Registered Sparks to do all the other work ie All the equipment required which would be the contactor , fused spur and connecting up and final testing , I have ocasionally got a tiler / Flooring installer to do the same , I would definiatelly find someone happy to do this before you go any further , remember that if you were to install such a system yourself , you would leave yourself wide open , not to mention the safety aspects , after all thats why we have test equipment and controls in place

 

[jamesricky674]

HI Nice discussion done on underfloor heating London here.

 

[danzor]

Can i do it myself and ask an electrician to come and check? And sign certificate?

Yes, I installed my own boiler and got the bar man to sign it off