701.753 vs manufacturers instructions

[mhar]

Customer wants underfloor heating in his bathroom and wants to use a B & Q Homelux mat. Downloaded manufacturers instructions and technical data to see if this mat complied with the above reg. As it didn't appear to be in compliance (fibreglass mesh as opposed to earthable metal) I emailed Homelux technical seeking clarification but this was ignored. Had a call to their technical helpline returned today to be told that the mat did not incorporate earthing but that the mat was designed for, and had been fully tested for, use in a bathroom and that thousands had been sold and were in use in bathrooms. Other makes of mat seem to be similar. Local wholesalers have not heard of a 'fine mesh metallic grid' for use in such circumstances which makes me think I may be misreading something
The builders proposed method of installation is existing concrete floor, insulation board, mat, waterproof tile adhesive, slate finish which, according to the manufacturers is exactly right. Surely there can't be thousands of EICs for notifiable jobs showing a departure from 7671 because manufacturers instructions have been followed?

 

[AndyL]

Does it not have a metallic sheath?

 

[mhar]

Not according to the person on the technical helpline. Haven't seen it yet. Thought it best to check before the event rather than after

 

[AndyL]

Does show on wiring diagram that it must be connected to earth, all the ones I have done in the past have had a metallic sheath

 

[mhar]

Sorry, misread your reply. Think I was envisaging the grid to be metalled. The helpline bloke stated the sheath to be teflon which sent me on the wrong track. Nothing to stop it being like a co-ax cable with the metal screening around it, all coated with teflon.
Well I would rather post something silly and end up happy than the other way round! Just making sure that I did not need to supply anything extra.

 

[SirKit Breaker]

Install it to the manufacturers instructions. The manufacturer has designed and made the thing, and if it is on sale in this country by a reputable retailer or "B and Q", then it will have to have met British Standards etc to prove it is fit for purpose and so on.

The manufacturers instructions are exactly that, and must be complied with for all sorts of reasons. The wiring regs are GUIDANCE ONLY, and the manufacturers instructions always take precedence.

Cheers…………….Howard

 

[mhar]

Thank you both.
When I looked up the instructions online I saw no specific statement that it was suitable for use in bathrooms hence my contact with the helpline, just to confirm - better safe than sorry. It was their (incorrect) response which made me think that I would have to note it as a departure. Clear now!!