What breaker size do you need for a MrCool mini split?
That’s quite easily answered. If you are wondering what fuse size (in amps) you need for your MrCool unit, just check the specification sheet.
Every MrCool specification sheet has a line with “Maximum Fuse (Breaker)” specs under the “Electrical Parts” section.
Here’s the problem:
These specs sheets for MrCool units are notoriously difficult to find. Yes, if you know where the specs sheet that came with the unit is, you just check that one. These specs sheets, however, get lost quite often. Googling for the MrCools specs and breaker sizes don’t always give you the answers you were looking for.
That’s why we have transcribed the breaker sizes for all MrCool units (including DIY units) from the specs sheets we haven’t yet lost. 🙂
You will find these maximum fuse sizes for all different MrCool series and units below. Let’s start with the best-selling DIY units:
Mr Cool DIY Single-Zone Breaker Sizes (20A, 25A, 30A)
The Mr Cool DIY Single Zone series is comprised of 4 different units; namely 12k, 18k, 24k, and 36k units.
Here are the breaker sizes as per the specs sheets:
|Model:||Serial Number:||Maximum Breaker Size:|
|Mr Cool DIY 12k||DIY-12-HP-WMAH-115B||20.0 Amp Breaker|
|Mr Cool DIY 18k||DIY-18-HP-WMAH-230B||20.0 Amp Breaker|
|Mr Cool DIY 24k||DIY-24-HP-WMAH-230B||25.0 Amp Breaker|
|Mr Cool DIY 36k||DIY-36-HP-WMAH-230B||30.0 Amp Breaker|
As you can see, the DIY series uses 20A, 25A, and 30A. Example: Mr Cool DIY 24k breaker size is 25 amps. This is the maximum size.
Mr Cool DIY Multi-Zone Breaker Sizes (20A, 25A, 30A)
With multi-zone mini splits, you have two breaker sizes you need to check:
- Outdoor unit – Heat pump condenser.
- Indoor unit – Wall-mounted air handler.
For the smaller 3-zone outdoor MrCool DIY unit (DIY-MULTI3-18HP230), you will need a 35A maximum breaker. For the bigger 4-zone outdoor unit (DIY-MULTI4-27HP230), you will need a 45A maximum breaker.
Here is a chart of MrCool DIY multi-zone indoor unit breaker sizes:
|Indoor Unit Model:||Serial Number:||Maximum Breaker Size:|
|Mr Cool DIY 9k Multi-Zone||DIY-09-HP-WMAH-230B||15.0 Amp Breaker|
|Mr Cool DIY 12k Multi-Zone||DIY-12-HP-WMAH-230B||15.0 Amp Breaker|
|Mr Cool DIY 18k Multi-Zone||DIY-18-HP-WMAH-230B||15.0 Amp Breaker|
|Mr Cool DIY 24k Multi-Zone||DIY-24-HP-WMAH-230B||15.0 Amp Breaker|
In short, all Mr Cool DIY Multi-Zone indoor units require a 15A breaker.
Mr Cool Advantage Series (20A, 25A, 30A)
Advantage Series MrCool units have to be installed by a professional. They are not DIY units.
Here are the breaker sizes for indoor and outdoor units:
|Advantage Model:||Serial Number:||Maximum Breaker Size:|
|Mr Cool Advantage 9k 115V||A-09-HP-WMAH-115B||15A Indoor / 20A Outdoor|
|Mr Cool Advantage 12k 115V||A-12-HP-WMAH-115B||15A Indoor / 20A Outdoor|
|Mr Cool Advantage 9k 230V||A-09-HP-WMAH-230B||10A Indoor / 15A Outdoor|
|Mr Cool Advantage 12k 230V||A-12-HP-WMAH-230B||15A Indoor / 15A Outdoor|
At higher voltage (230V) you need less amps to generate the same amount of power (wattage). That’s why you need bigger breakers with 115V MrCool Advantage units.
MrCool Olympus E Star Series Breaker Sizes
These are older MrCool models. Here are the breaker sizes:
|Olympus E Model:||Serial Number:||Maximum Breaker Size:|
|Mr Cool Olympus E 9k||O-09-WMAH-230A||15.0 Amp Breaker|
|Mr Cool Olympus E 12k||O-12-WMAH-230A||15.0 Amp Breaker|
|Mr Cool Olympus E 18k||O-18-WMAH-230A||20.0 Amp Breaker|
|Mr Cool Olympus E 24k||O-24-WMAH-230A||25.0 Amp Breaker|
MrCool Olympus Hyper Heat Series Breaker Sizes
|Olympus Model:||Serial Number:||Maximum Breaker Size:|
|Mr Cool Olympus 9k||O-09-WMAH-230A||15.0 Amp Breaker|
|Mr Cool Olympus 12k||O-12-WMAH-230A||15.0 Amp Breaker|
|Mr Cool Olympus 18k||O-18-WMAH-230A||25.0 Amp Breaker|
|Mr Cool Olympus 24k||O-24-WMAH-230A||30.0 Amp Breaker|
This is about it. If you would need a to know a breaker size for a specific MrCool model, just use the comments below and we’ll find the breaker size for you.