warm up underfloor

[musicspark]

Ok Guys

It's the floor probe - flexible conduit or not?

I have had differing sets Ideas on this; some say 10m flexible to the stat box

and chisel a bit out of the insulation board, others just lay it in 300mm and screed it in,

So , who's done lots of this stuff?

 

[Northern Electric]

I can help you here.

I have installed loads of this stuff, I have it in all my bathrooms, conservatory and kitchen.

On a concrete floor I usually install some Wedi tile backer boards before laying the matting. I use the thickest backboard I can get away with. I then roll the heater mat out around the floor.

If you are using the Devimat, which I much prefer, the stat comes with floor sensor and a piece of 10mm flexible conduit. I channel out the insulation board to run the conduit and position the sensor at roughly 300 mm from the wall, away from the element, of course. Once all of the system is in place ensure you test it throughly with a megger and continuity meter. Don't megger the sensor though!

The last thing I do before tiling is pour a flexible latex leveling compound over the whole area to encapsulate the system, this is optional, but it helps stop heavy handed tilers from damaging the element.

Remember all tile adhesive used to fix the backer boards and the tiles must be flexible adhesive.

 

[Northern Electric]

Here's the instructions for the system I install.

I missed the fact you are using Warm Up heating.

http://www.devi.co.uk/downloads/devimat/08098002.pdf

 

[kme]

As regards the warm-up, which is the system being specified.

Put the sensor in a small piece of pipe, and cover the ends of the pipe with some of the grey tape. If you bury the sensor in the floor, you will have a nightmare of a job as and when it fails.

I`ve fitted this stuff for years (see previous thread about it), and know from early experience that customers get somewhat peevish when you start chipping tiles up to find the sensor when it fails!!!!!

HTH

KME

 

[sellers]

How can you tell if there is a failed sensor? can I test its resistance?

 

[Northern Electric]

Yes KME,

I forgot to mention to cover the sensor with tape or something similar. Thank you.

Warm up was the system specified in the title, I missed that. It all does the same thing and installed in a similar way.

With the Devi system I have not known a sensor fail, though no system is infallible.

The sensor can be tested with an ohm meter. The instructions usualy state the given resistance of a sensor.

 

[kme]

How can you tell if there is a failed sensor? can I test its resistance?

Use an ohm-meter (NOT a megger). An MFT will usually NOT do the job, as you are looking for 10-20Kohms, on the warm-up sensor.

Neil. I have known a devi sensor fail, as well as 2 of their ribbon mats. Personally, I prefer the warm-up. It seems to be better quality, easier to work with and more cost-effective.

My opinion.

KME

 

[Northern Electric]

Fair enough, I have only installed a few systems myself, no more than 20. I have always had good reports about the Devi system from others, though not too many lads I know like to get involved with it, underfloor heating in general, that is.

 

[musicspark]

thanks guys

customer specified warm up

what are the advantages or differences with DEVI?

 

[Northern Electric]

I cannot comment on Warm up as I have not fitted it, KME seems the boy to assist you on that one.

 

[NozSpark]

I've been looking at getting and installing a UFH kit for someone (all before have supplied) andthe WarmUp seems to have a much lower w/sq m than many of the other makes that are out there.. for a similar price

 

[kme]

I find that to be a good thing - dry UFH, esp. in a large room, can be hugely energy intensive. If you`re using the loose wire, I generally only use approx 60-70% of the suggested size- from experience you end up with the wire packed too close, and you have massive problems dissipating the excess - you cannot cut to size.

Another issue - most of the programmers are the same unit, with manufacturers labelling. Max loading is usually 16A - more than this needs a contactor. However, the programmers have a serious issue with the EM pulse generated by most contactors. You MUST remember to fit a snubber across the coil.

HTH

KME