Now that the house and the bonus room are complete I checked and the builder only ran a 12-2 wire (2 insulated wires and a bare ground). We can determine the size of your heat pump from the model number. So would that be the only way the unit didnt turn onsomeone had to have flipped the breaker? A larger 12,000 BTU unit draws between 9 and 13 amps. Are cassettes sufficiently sealed / fire rated such that you can pile 32 of blown in fiberglass insulation directly on top of them without heat or fire issues? Here your labeling will tell you whether or not the unit you are looking at is an AC, or its slightly more energy-efficient cousin, the heat pump. BTU stands for British Thermal Unit, and its a measurement of how much energy it takes to heat 1 pound of water by 1 degree. It may be worth investing in a lock for your disconnect switch. Depending on the BTU capacity amp requirements can range from 15 to 45 amps. The watt (W) is a unit of power. How many watts does a 18000 BTU air conditioner use? You can also cut the ends of the wire to check it visually: copper wire is golden brown, while wire made from aluminum is dull gray. 2 How many amps does a 18000 BTU Mini Split use? You can also throw unnecessary costs into the equation even more to the point. It is also critical to make sure that each indoor unit on a multi-zone system is wired to the same input that its line set is connected to. A one-ton unit with one outdoor and one indoor component at 21 SEER rating runs $1,000 to $4,000 depending on the brand and type of indoor mount. But what exactly does it mean when an AC unit is one ton, and how does that help choose breaker size? How many amps does a 18000 BTU Mini Split use? This will help you operate the mini split more efficiently and save you money on your energy bill. We know that we are running it for 8 hours. Next, we will discuss the max breaker size for a heat pump or air conditioning unit. 21 SEER: 24000 BTU Inverter Mini Split Heat Pump: Enjoy full season comfort during the summer or winter with this 24,000 BTU Inverter Mini Split with 27,000 BTU Heat Pump.WHAT IS DC INVERTER? What is the fastest way to harden salt dough? There are many variables to consider when choosing a breaker and wiring an air conditioner (AC) in your home. Thanks! In other words, the wire is slightly larger than the electrical current rating. Assuming the 18,000 BTU air conditioner operates at 120 volts, it will consum. Central systems often require the most power, while window units require the least.Unit TypeBTU/HourBreaker Size (Amps)Typical VoltageCentral AC24,000-60,00020-60220VMini-Split AC12,000-24,00015-20220VWindow AC6,000-12,00015110V.