AC Cable Size

[cigar7]

The Mitsubishi MS-SGH18VC air conditioner has an electrical rating of 5.1 Kw. Is a 2.5mm cable adequate to feed this beast? Is a 20 amp. adequate or should it be a 32 amp.?

[bankruatsteve]

If you are in a position to choose, you should go with 4mm and 32a breaker.

[bankruatsteve]

Usually somebody else will qualify things but not yet - so I'll give it a go...

2.5mm2 can handle the 23amps that your A/C might demand although that would be at the threashold. A 20a breaker could likely trip. You could see how it goes, if that's your situation, and if it does trip you could put in a 24a breaker and still be OK.

Again, if it's a new install, go with the 4mm2 wire and 32a breaker and then there will be nothing to worry about.

[Crossy]

The Mitsubishi MS-SGH18VC is an 18,000BTU (5.1kW) cooling capacity unit, it will draw about 2kW (10A) from the supply when running.

2.5mm² on a 20A breaker is just fine, I would still install 4mm² if it's a new installation to minimise volt drop and allow for future upgrades.

[Naam]

electrical rating of 5.1 Kw

mixing up cooling capacity with electrical consumption is nowadays quite common.

[cigar7]

The Mitsubishi MS-SGH18VC is an 18,000BTU (5.1kW) cooling capacity unit, it will draw about 2kW (10A) from the supply when running.

2.5mm² on a 20A breaker is just fine, I would still install 4mm² if it's a new installation to minimise volt drop and allow for future upgrades.

I finally got an answer from Mitsubishi on unit's power requirement. On "powerful mode" which probably uses the most power, I'm told it needs 1,470 watts.

Here is their exact reply - Powerful mode due to the compressor runs fixed speed the unit charge constant current ( 1470 wat =220Vx6.9 ampere in sheet 2 )

[cigar7]

If anybody else is interested in the specs for this AC unit, attached is a document from Mitsubishi. It recommends a 15 amp circuit breaker, run current is 6.9 amps and start is 34 amps.

20150827150832047.pdf