• Click here to access some of the presentations made during the 2022 National Rally

Mini split

Gleninaz

Member
I live in Arizona with my dog. Trailer was getting hot at 107 outside last week so I put the Reflectix on all the windows. Lowered the temp by 5 degrees. Still warm in the main living area. I ordered a mini split and will install it but don't have a clue how to wire up the compressor. Wondering if there are any unused breakers in the box in the trailer? I will hire an electrician but figure for a 110 compressor it would be easier if I have an unused breaker.
 

Jim Beletti

Elite Member
Open the lid on your AC breaker panel and take a look at it to see of you have any blank spots.

Which mini-split (brand and model) did you buy? Is it a 120v or 240v system? When using shore power to run a 240v mini-split, you'll need 50A power as it will be the split-phase power a 240v mini-split needs.
 

Jim Beletti

Elite Member
Hi @Gleninaz - few of us on this forum are electricians are HVAC techs. So please be careful with the assistance you receive here and treat is as ideas / guidance and not as a how-to. The how-to is on you to know or learn or hire-out.

That said, I took a look at the manual for one Mr. Cool mini-split and gleaned the info below. It's doubtful I correctly guessed your model number, so use this info carefully and cross check with what you actually have and the manual that came with it.

A 115-120V unit will require 3 conductors of the correct wire gauge. Those conductors will connect to your power system's line, neutral and ground. Generally speaking, all 3 can be found inside the AC panel box:
- L (line) will come from a breaker
- N (neutral) will come from the neutral bus
- G (ground) will come from the ground bus

Wire Diagram.png

Use of the proper AC wire gauge is critical for all AC wire circuits. Below is a table from a Mr. Cool mini-split manual showing the minimum wire gauge to be used based on the size of the mini-split model.
I urge you to have a conversation with Mr. Cool customer support, detailing your installation plans with them and let them guide you on aspect such as:
- Mounting ideas of outdoor unit
- Ventilation idea of outdoor unit
- Wire type, gauge and jacket/conduit type for outdoor unit
- Circuit breaker type and rating for outdoor unit

Wire Gauge.png
 

Jim Beletti

Elite Member
I bought a 25' 30 amp power cord with wires on one end and hard wired it to the compressor. Just plugged it into the 30 amp on the post and ac is blowing 47 degrees and super quiet.
Wow - that's great news. Can you share some pictures of your installation (indoor and outdoor units?
 
Top