Power requirements for mini split systems are:
110/120 Volt: Most mini split systems up to 12,000 BTUs can use this voltage.
208/220 Volt: 6000 BTU and higher.
It seems strange that some 6000 BTU mini split ACs and heat pumps would use 208/230V power, but it is true.
Let’s get into the details.
The Mini Split AC/Heat Pump is becoming the method of choice for heating and cooling home additions, workshops, and garages, just to name a few places popular for installation. Mini splits are powered by electricity, so there is the need to extend an electric service line to the area where the outdoor component will be located.
This article focuses on the electrical connection that will provide the proper voltage and watts needed to power mini splits of different sizes. Easy-to-read charts are included, along with examples of how to use them, which will enable you to quickly find the information you need.
There are FAQs at the end of the article.
How a Mini Split Works
A mini split system may either be for a/c only, or a heat pump, which will provide both cooling and heating. They have similar electrical needs, so the information found here can apply to either type.
The mini split has two main units. The condenser is the outdoor unit. The evaporator or air handler is the indoor unit. Between them is a line set, aka lineset, which includes two insulated copper tubes through which the refrigerant flows. Electrical wiring and a drain tube are often bundled with them.
An electrical service line must be run from the main breaker panel in the building to the mini split outdoor unit. This provides all the power needed to run both components of the system. The size of this wire will be determined by the type and size of the mini split system being installed.
The Critical Electrical Connection
The normal configuration of the electrical connection for a mini split consists of the following:
1. A dedicated circuit breaker or breakers in the main service panel of the building. These breakers act as the surge protector for the mini split.
2. Wires of the appropriate gauge (thickness) for the mini split to be installed. These wires are to be run all the way from the main panel to a disconnect box on the outside of the building within just a few feet of where the outdoor unit will be located. Note – the lower the number of the gauge, the thicker the wire. For example, 12-gauge wire is thicker than 14-gauge wire.
3. The disconnect box has either a switch or a removable “plug” that will shut off all power at that point. It may have another fuse or circuit breaker in it. The disconnect box is there so the power may be easily and safely removed from outside the building when the system needs maintenance or repair.
4. The connecting cable provides electrical power to the entire system. This could either be wire that is approved for outdoor use, or an electrical whip, which is a waterproof tube which looks somewhat like a garden hose through which wires are run. Whichever one is used, the connecting cable extends power from the disconnect box to the condenser unit of the mini split.
Mini Split Power and Wire Requirements
All electrical appliances and systems need wires of the correct size (gauge) to safely and efficiently handle the amount of current the system will use. Some of the smaller mini splits operate on 110 volts, while most need 220 volts. Here are some charts that will help you choose the correct wire gauges and circuit breakers for your system.
110V Mini Split Power Requirements
It is important to get the proper wiring for the safe, effective operation of a mini split heating and cooling system.
110v Mini Split Wire Size
|110V Mini Split||Minimum Circuit Ampacity||Wire Size|
|9000 BTU||14 Amp||12 Gauge|
|12000 BTU||15 Amp||12 Gauge|
How many amps does a 12,000 BTU mini split use? You can see from the chart above that the answer is 14 amps. And to determine what size wire for 12000 BTU mini split? The chart tells you that you should use 12 gauge wire.
110V Mini Split Breaker Size
|110V Mini Split||Breaker Size|
|9000 BTU||15 Amp|
|12000 BTU||20 Amp|
Do you need to know the recommended 12000 BTU mini split circuit breaker size? The chart shows that it should be 20 amp. Notice that the 9,000 BTU system only requires a 15 amp circuit breaker. This tells us that the more cooling power a system has, the more electrical power it will require.
220V Mini Split Power Requirements
As noted, all mini splits larger than 12000 BTUs use 220 power.
220v Mini Split Wire Size
|220V Mini Split||Minimum Circuit Ampacity||Wire Size|
|9000 BTU||12 Amp||12 Gauge|
|12000 BTU||15 Amp||12 Gauge|
|18000 BTU||18 Amp||10 Gauge|
|24000 BTU||20 Amp||10 Gauge|
|30000 BTU||22 Amp||10 Gauge|
|36000 BTU||25 Amp||10 Gauge|
What size wire for 18,000 BTU mini split? This chart says you should use 10 gauge wire. The answer to: What size wire for 24000 BTU mini split? It is the same as the other larger sizes on the chart – 10 gauge.
220V Mini Split Breaker Size
|220V Mini Split||Breaker Size|
|9000 BTU||15 Amp|
|12000 BTU||15 Amp|
|18000 BTU||20 Amp|
|24000 BTU||25 Amp|
|30000 BTU||30 Amp|
|36000 BTU||30 Amp|
What size breaker for 24,000 BTU mini split? A 25 amp circuit breaker is the correct size for a 24,000 BTU mini split. Using a 30-amp breaker is fine too.
Should I Use A 10/2 Or 10/3 Wire For A 220v Mini Split?
Definitely use 10/3 – and this should also have a ground wire (“10/3 w/ground”). While a 110v system only needs two wires to conduct the electricity, a 220v system requires three. Two of them are considered “hot”, and one of them is the “neutral”. The additional ground wire is a safety measure to prevent a house fire or an electric shock if there is excess electricity in the wiring system.
Mini Split Power and Wire Size FAQs
What is 14 4 wire for mini split systems?
Some mini split heat pumps require a 4-conductor control cable. The installation manual for your ductless system should specify what wiring is required.
Is a 110 or 220 mini split better?
It depends on what “better” means for you. Here are some ways to compare a 110v and a 220v mini split:
1. System Cost – Generally speaking, a 220v mini split will cost more than a 110v system of the same brand, BTU, and SEER. This could vary, depending on sales, special discounts, etc.
2. Installation Cost – a 220v mini split will require an additional circuit breaker and more expensive wiring than a 110v mini split. This means the installation cost will be higher for a 220v mini split.
3. Efficiency – this is the SEER rating. The voltage of a mini split system does not affect its efficiency.
4. Operating Cost – this will be the same with either voltage for models of the same BTU and SEER.
Are there any 18,000 BTU mini split for 110 volt power?
To our knowledge, only mini splits that are 12,000 BTU and smaller are available in 110v models. 18,000 BTU and larger all require 220 volts.