Which cable for Air Con power?

[Damian30]

Hi

My Mitsuibishi Electric out door air conditioning unit requires a 3 core 1mm cable to a 10amp breaker. I'm going to be using an electrician to complete the final connections, although want to get all the parts sorted.

I was thinking SY or SWA cable (it's going to be used in a domestic setting). My plan was also to use a MK Masterseal Plus fused connection unit but may go back to the more traditional rotary isilator, especially if the thicker SWA cable is used.

If anyone has any experience of connecting these units, I'd be very grateful to receive any thoughts.

Many thanks,

Damian

 

[bernardgreen]

As you are employing an electrician to make the connections you might as well ask him to supply the parts and cable. He may even have an off cut of cable that he can use thus saving you the full cost of the cable.

Depending on the unit and access to it ( outdoor ) a rotary isolator that can be padlocked in the OFF position may be necessary

 

[Damian30]

Hi,

Thanks for the feedback - I think you are right re cable selection.

The outdoor unit is in a secure area in a domestic property. I've bought an MK Masterseal Plus fused spur but might get a rotary isolator instead. Out of interest, most of these isolators are 20amp +. I'm guessing you can get special fuses for these things at 10amps? Noddy question I know but I honestly don't know much about these things.

Thanks,

Damian

 

[wingcoax]

The isolator will not be fused. The 20a rating is what the contacts can take, the fusing would be done either in your CU or by a FCU.

 

[ericmark]

I or at least my firm got caught out with two part air conditioning units. We were told high power required to indoor bit, but when they arrived found high power required for outdoor bit which involved routing a 150 mm² cable to the roof. There were many units up there.

My foreman assured me the last one he had fitted was the other way around with compressor built into indoor bit.

I would there for wait for the units to arrive and let the electrician decide where to run cables. It is a specialist job. We had a second problem where the condensate pipe became disconnected and as a result brought down part of the ceiling lucky before the store was opened to public.

Up to that point all the AC's I had worked on were self contained units which fitted into a large hole in the wall. I just thanked my lucky stars I was not the foreman on that job as I could have so easy made the same mistake.