I am updating my breaker box later today (work being done by an electrician) to add additional power to my garage. I've run the wires for two 20 amp circuits but I would also like to run the proper gauge for a later install of a mini-split unit. Do I need anything larger than 12-3? Oh - the electrician works in a secure building so I can't call him and I want to have everything laid out to save him time. Thanks in advance.
Need wire size
- Thread starter steve308
- Start date
theoldwizard1
Well-known member
Not enough info. We need distance and current draw.
15000 btu unit heat pump-AC / box to hook up will be 25 - 30ft in length
TYPE: Heat Pump (Inverter)
Performance Ratings:
•Size: 1.25 TON
•SEER: 21.0
•EER: 13.0
•HSPF: 10.0
•Cooling Capacity: 14,000 Btu/h
•Tax Credit Qualify: Yes
Outdoor Unit: MUZGE15NA
•Height: 21 5/8"
•Width: 31 1/2"
•Depth: 11 1/4"
•Min. Amp: 12.0
•Max. Fuse: 15.0
•Liquid Line: 1/4"
•Suction Line: 1/2"
•Max. Refrigerant Pipe Length: 65'
•Max. Refrigerant Pipe Height Difference: 40'
Indoor Unit: MSZGE15NA
•Height: 11 5/8"
•Width: 31 7/16"
•Depth: 9 1/8"
•Min. Amp: 1.0
•Max. Fuse: 15.0
Thanks
TYPE: Heat Pump (Inverter)
Performance Ratings:
•Size: 1.25 TON
•SEER: 21.0
•EER: 13.0
•HSPF: 10.0
•Cooling Capacity: 14,000 Btu/h
•Tax Credit Qualify: Yes
Outdoor Unit: MUZGE15NA
•Height: 21 5/8"
•Width: 31 1/2"
•Depth: 11 1/4"
•Min. Amp: 12.0
•Max. Fuse: 15.0
•Liquid Line: 1/4"
•Suction Line: 1/2"
•Max. Refrigerant Pipe Length: 65'
•Max. Refrigerant Pipe Height Difference: 40'
Indoor Unit: MSZGE15NA
•Height: 11 5/8"
•Width: 31 7/16"
•Depth: 9 1/8"
•Min. Amp: 1.0
•Max. Fuse: 15.0
Thanks
BillK
Well-known member
If these specs are correct then #12 wire should be fine. It looks like they want no more than a 15 amp breaker for both units.
Personally I would wait and ask the electrician though, just to be certain.
theoldwizard1
Well-known member
I think you have your part number wrong ! I believe the outside unit should be a MSY-D30NA, which, according to the spec sheet requires a 25A breaker.
Of course, this means 10-3 copper wire
FYI : The 36,000 BTU model (MSY-D36NA) will also run on a 25A breaker.
Of course, this means 10-3 copper wire
FYI : The 36,000 BTU model (MSY-D36NA) will also run on a 25A breaker.
Specs were copied and pasted directly from 'Mitzi" spec sheet. Should I install the 10-3 just to be on the safe side? I am a subscriber that to much is just short of enough. (Room in question is 400 Sq. with vaulted ceiling so I think I should be OK with the 15000 unit)
According to mitsu's website, min circuit ampacity is 12A for that unit (220v), add 20% to that an a 15A circuit is fine. 12-2 should be just fine.
Don't forget to look up the requirements for the indoor unit. I think mine required a 16-3 300v wire to connect it to the outdoor unit.
Don't forget to look up the requirements for the indoor unit. I think mine required a 16-3 300v wire to connect it to the outdoor unit.
Highbeam
Well-known member
10/3 is pretty cheap, so is 12/3. It's when you get to the #8 wire that the price really jumps. 10 gauge is easy to work with with regular wire nuts.
theoldwizard1
Well-known member
Page from the catalog I have is attached.
Oversized wire is much better than undersized !!
Attachments
You do not need to add anything, the manufacturer has done that already, MCA = Minimum Circuit Ampacity, the MOCP = Maximum Over Current Protection, Per NEC art. 440 you get to wire to the minimum & install the maximum allowed overcurrent protection device allowed by the label.
The rules for A/C equipment are different then "normal" branch circuit wiring, so things that are wrong for a branch circuit can be just fine & code compliant on a A/C.
ixlr8
Well-known member
I have the same unit, 12-2 is fine, I have similar distances. Inside unit got it's power from the outside unit and that wiring came with the unit. Although, I did have the HVAC company install the unit so maybe they are the one's who supplied the inside to outside wiring, I know I didn't. I just supplied the 12-2 to the outside disconnect I put in.