Do I need SWA?

[Crofter]

We're having an ASHP installed. There will be an external isolator next to the unit, fed on its own circuit from the CU.

Quick question: is it acceptable to use T+E cable through the external wall and in to the rear entry of the isolator?

Or does this call for SWA?

[ProDave]

T&e is fine if not exposed, i.e straight through the wall into the isolator.  Flexible conduit is often a better option from the isolator to the ASHP rather than SWA.

[Crofter]

1 hour ago, ProDave said:

T&e is fine if not exposed, i.e straight through the wall into the isolator.  Flexible conduit is often a better option from the isolator to the ASHP rather than SWA.

That bit will be up to the ASHP installer.

But I guess you could use conduit over the T+E if for any reason going straight in to the back of the isolator didn't work?

[Crofter]

As usual, once I started looking properly at the situation my plan fell apart. I'm going to have to have a run of cable outside the house, coming up to the underside of the isolator. It's either that or rip open a tiled wall! 

 

So I guess the choice is SWA vs T+E in conduit? The former is maybe better but requires a junction box.

[ProDave]

T&E in conduit is fine with the added advantage of no junction when going from outside to inside.