Using UPVC Cable inside Boiler for Programmer

[self builder 123]

Hi

I had to replace the built in programmer on my oil fired boiler with an external programmer.

I did not have 0.75 sq.mm flexible cable to hand so I used 1.5 sq.mm grey UPVC coated cable ( typically used for lighting circuits ) to connect up the external programmer.

I ran the UPVC cable inside the boiler keeping it away from any hot surfaces.

Will this cable be okay to leave inside the boiler ?

Why is flexible cable mentioned in the installation instructions for oil fired boilers in general - is it simply easier to run / use or is it rated for a higher external temperature ?

Many thanks.

 

[DP]

PVC cable is single strand. Single strand cable, especially 2.5mm I have seen used sometimes, will easily dislocate terminals even pull terminations off the PCB. Best to use heat resistant flex. 3 core ok for supply, 5 or 6 core if controls are used. Looks a lot tidier.

 

[self builder 123]

Cheers DP

One other question - when I replace the UPVC with flex do I need to earth the programmer backplate to the boiler ?

The programmer is fixed to plasterboard wall - no metal single gang back box and so I was thinking that an earth lead would serve no purpose in this particular application as the programmer is fully insulated in a plastic housing ?

Cheers

 

[mikely]

You should provide an earth at the programmer. You may not require it for your programmer but it may be required in the future. Any suitable cable you use to connect the programmer (e.g heat resistant multicore or twin & earth) will include an earth core which should only be used as an earth connection.