joining

[Spare Tool]

Have to join 2 x 10m matts together and the guy in the tile shop said the thermostat will only take 18sqm maximum unless a connector box is used before the thermostat...he didn't know the ins outs and whyfors though, does it just protect the thermostat or actually drop the wattage into it.. any one shed any light on it

 

[Stef]

There was a thread last week on using 2 mats to one thermostat, go through that as the guy from U heat commented on it, it might help you out.

 

[Spare Tool]

Read that one thanks Steff ...its just about joining 2 matts straight into the thermostat, not about using a connector box because off exceeding the maximum wattage.

 

[Stef]

Ah ok, not something I've done before.

 

[Spare Tool]

Me neither, hopefully someone will know the script with it as the sparkie i use didn't seem to know what i was on about either...worryingly

 

[Spare Tool]

My mistake its called a contact box not a connector box...still don't know what it does though

 

[Sean SML Tiling]

If your not sure then swap it for the loose cable kit. I never use mats because of this and find the loose cable much easier to work around things.

 

[Spare Tool]

Using a loose cable wouldn't make any difference to the amount of amps\watts needed to go into the thermostat i still need to heat 20sqm

 

[Tile seller]

Snubbers/contactors , they act as a relay. Most thermostats can only handle 15 /16amps. The thermostat then just acts as a switch for the snubber, which will then switch the heavy load .

That said, with 20msq to cover, if your matts are 150w per msq,(not 200!) then you will pull 12.5amps. however, if there 200w per msq then its 16.66 amps, which is over the thermostats rating.

18msq is the max as 200w per msq is often the max, which then pulls 15amps, which is often the lowest rated thermostat. It's a simply safety default.

If in any doubt contact the heating matts manufacturer, they should be able to give you the advice you need.

 

[Old Mod]

With warm up either mat or loose wire (pro wire) u can add two zones to one thermostat as long as the total Amps drawn are below 16 Amps. Any more then u have to add your contact box which handles the extra load over 16 Amps. A 10m2 area requires two DSW 800's which is 1600 watts and 6.96 Amps. So two zones 4 DSW 800's = 13.92 Amps.
Call technical to confirm first tho.

 

[Time's Ran Out]

You need a decent electrician to give you the right advice. You can lay the mats but it's up to him to make them work.

 

[Spare Tool]

Thats the answer i was looking for, so if the ufh was 200 watt do you happen to know the total amps and if this would push it over the 16amp limit?
Thanks Andy

 

[Old Mod]

Should tell u in the instructions what each mat draws in amps. Each system will be different probably. I can only quote warm up cos that's all I use. There's has a maximum of 16 amps before your contact box is needed.

 

[Spare Tool]

John he's a very decent electrician been sparking nearly as long as you've been tiling... that's the trouble with the old schoolers, slow to follow with the times

 

[Old Mod]

If it's any kind of help warm up 200w 10m2 mat draws 8.7 amps. That'll push u over. Loose wire draws less.

 

[Spare Tool]

That helps a lot thanks, so what's the purpose of the contact box does it just protect the thermostat or does it drop the amps entering it...sure my electrician will sort it, just so I've got it straight in my head

 

[Old Mod]

Yeah pretty much. It deals with extra load. That's all I know.

 

[Spare Tool]

Thanks for your help..
Cheers Andy

 

[Uheat - Keith]

Agree with Tile Seller & 3-fall & timeless John above.

if it is 200w/m2 system at 18m2 = 3600w = 15.65amp.
Your electrical engineer will need to install a contactor or relay at 20 amp.
Hope that helps, warm regards,