Interconnecting / Power question

[rgeggs]

Hi all,

I’m mainly a service engineer but have a small install coming up, and I’m after some help. The customer has an old LG wall mount which he wants replacing with a new Mitsubishi Heavy system. The current unit is power to indoor, with a switch next to the indoor unit. This then runs to the outdoor unit in a 5 core cable (LNE + 2 control wires).

The new system is power to outdoor. Due to the layout of the building there really is no scope to run a new power cable from the board to the outdoor unit.

So - what is the best/easiest/safest way to do this? Could I just take the LNE from the switch straight to the 1+2+E connections on the indoor unit interconnecting terminal, then from there straight to the outdoor unit on the 5 core?

I know none of this is ideal but it is the hand I’ve been dealt. Thanks in advance.

[frank]

Assuming that this is a domestic property then you will need a Part P registered electrician to install the power to outside.

[Smithsair]

A lot of air conditioners allow you to run the mains to the indoor (1,2,3,E) and then down to the outdoor unit. Just make sure the cables are large enough to withstand the current draw. Saying that, there are a couple of manufacturers like Fujitsu that have the power running through an outdoor Filter PCB first then runs up to the indoor unit. If you are going to do it then speak to the manufacturer first to make sure power doesn't need to run through any PCB before it hits indoor.