Best Mini Split Heat Pumps

We are familiar with the fact that hot objects gradually cool off. The heat dissipates to the surroundings. A hot cup of coffee or a bowl of soup cools off in a few minutes. The chemist Antoine Lavoisier proposed that there was a fluid called “caloric” that flows from hot objects to cold objects. (It was later proven that no such fluid exists--which led to the correct idea that heat is rather due to the motion of the particles in a material that make it hot.) A heat pump is a device that makes heat go in the opposite direction: it will take energy from outside your home, and pump it into your house. There is of course a limit to how much that they can do this. If the outdoor temperature doesn’t usually go below 25 degrees Fahrenheit (which is still pretty cold), most heat pumps will still succeed in squeezing that thermal energy out of the outside air and bringing it into your home. It is an economical way to heat your home, that comes out cheaper over the course of the winter than using radiators or convection ovens. And many mini-split heat pumps will serve as an air conditioner in the summer!

A mini-split heat pump is one of the cheapest ways of heating your home. It is “split” into two devices: 

• An outdoor unit, consisting of a compressor, condenser coil, and fan, and

• An indoor air handling unit, with an expansion valve, evaporator coil, fan, and air filter. 

In a multi-zone version, there is an air-handling unit installed in each room, providing it with warm air. If your home has ductwork installed, you can find mini-split pumps that send hot air through the ducts. And if you don’t have ductwork installed, there will be mini-split heat pumps that can heat your home nonetheless. But you should learn a little about the specifications of heat pumps, to make sure that it will be able to heat your home efficiently.

We’ve composed this buyer’s guide to help you make the right decision when selecting a mini-split heat pump. It'll help you:

• Choose the right type of mini-split heat pump,

• See useful tips about that particular type of mini-split heat pump,

• Read reviews of different mini-split heat pumps, and what customers are saying, 

• Select the right brand of mini-split heat pump, and 

• Compare prices and find the best deals. 

We will examine some of the most popular geometries of mini-split heat pumps:

• Wall Mount: This consists of a compressor that you install outside in your yard, to the wall of your house, or on the roof, and the air-handling unit from which the hot air exits into your room. This is not just the most popular geometry of mini-split heat pump--it is also one of the most efficient ways of heating your home in general! It can also be installed so that it remains inconspicuous and even elegant. 

Pioneer Heat Pump Model No. WYS009GMFI19RL-16

• Ceiling Cassette: In this model, the heated air will come out through a unit in the center of the room’s ceiling. The heat then dissipates evenly throughout the room. An example is the Pioneer 12000 BTU Compact Cassette Mini-Split (Model No. CYB012GMFILCAD-16). 

Pioneer 12000 BTU Compact Cassette Mini-Split (Model No. CYB012GMFILCAD-16)

• Concealed Duct (or “Ceiling Concealed”): This is a ducted model. Installing it requires that your home is already provided with ductwork. The air handling evaporator unit is inserted into the ceiling so that all that is visible are the unit’s louvers. An example is the Pioneer Air Conditioner Inverter++ Split Heat Pump (Model No. RYB018GMFILCAD).

Pioneer Air Conditioner Inverter++ Split Heat Pump (Model No. RYB018GMFILCAD)

• Ceiling Suspended: These have one side attached to the ceiling, suspended by rods and adjacent to one of the walls of the room.  Fujitsu’s Halcyon Model 36RSLX is such a model.

Fujitsu’s Halcyon Model 36RSLX 

• Floor Standing: These are also called “Floor Mount” systems. This is good for a kitchen or den area, with an angled ceiling. It is installed with its back against a wall of the room--it’s not uncommon to place it under a window. Fujitsu’s RLFFH Series are floor standing units.

Fujitsu RLFFH Series Floor-Standing Heat Pump

• Getting the right size for your room: You’ll want a heat pump that matches the dimensions of your room. The number of BTUs produced by a heat pump will be a good indicator of the size of the room it can heat. Here are recommendations for heat pump capacities for their respective areas:

  • Room size from 250 sq. ft. - 450 sq. ft.: 9,000 BTUs

  • Room size from 550 sq. ft. - 800 sq. ft.: 12,000 BTUs

  • Room size from 750 sq. ft. - 1100 sq. ft. : 15,000 BTUs

  • Room size from 850 sq. ft. - 1250 sq. ft.: 18,000 BTUs

• Extend the line length: There are kits for extending the line length between the indoor and outdoor units. The Pioneer 9000 BTU Heat Pump (Model No. WYS009AMFI17RL) comes with a 16-foot line by default. But you can also get a kit extending as far as 50 or even 80 feet as well! 
• Ductless units cheaper to install: You’ll need professional help in installing a mini-split heat pump since it involves drilling a 3” diameter hole in the wall for the refrigerant pipes and cables connecting the two units. But this is far less expensive than installing ductwork in your home. Also, much less heat is lost in ductless mini-split systems as compared to the heat loss resulting from heat traveling through the ducts. It’s estimated that 30% of the heat is lost through a duct system. But there are also mini-split pumps that utilize existing ductwork, such as the Pioneer Air Conditioner Inverter++ Split Heat Pump (Model No. RYB018GMFILCAD).

• Programming the unit: Many mini-split heat pumps will use a remote control or even Wifi for programming the on-off scheduling of the unit. You can get the accuracy down to as fine as five-minute intervals!

• Precharging with refrigerant: There is also the issue of adding refrigerant to the mini-split heat pump. Frequently, the outer unit is precharged with refrigerant. Once all the lines are set up between the indoor and outdoor units, you need to vacuum out the air in the pipes so that it’s pure refrigerant inside. It’s best to ensure that your unit uses an environmentally-friendly refrigerant with no fluorocarbons. One example is the R410a refrigerant, as is used in the MrCool units.

• Determining your heat pump’s efficiency: There are two specs that you’ll see on mini-split heat pumps: The HSPF (= Heating Season Performance Factor) is an indication of the heat pump’s efficiency. It will be a number ranging from 7.7 to 12.5, with 12.5 being the highest. It is calculated by taking the number of BTUs that the heater produces, divided by the power that the heat pump consumes, in kilowatt-hours. So, if the Pioneer Split Heat Pump produces 18000 BTUs of heat and consumes 1.7 kilowatts of power every hour, the HSPF = 18000/1700 = 10.5. As for using it for cooling in the summer, look at the SEER ( = Seasonal Energy Efficiency Ratio). It is the cooling output in BTUs divided by the energy consumed in kilowatt-hours. Since 2015, it is required that air conditioners have a SEER of at least 14--and the higher, the more efficient. There is also the Coefficient of Performance (= COP), which is the heat that the device provides, divided by the work required to get that heat output. So a heat pump that provides a lot of heat for a minimum of work will have a higher COP. The COP will usually be from 3.1-4.1. 

Pioneer Air Conditioner Mini-Split Heat Pump (Model No. WYS009AMFI17RL) SEER and HSPF ratings

• Pioneer is a manufacturer of mini-split heat pumps and air conditioners, for both ducted and ductless houses. They make wall-mounted, ceiling cassette, floor-ceiling mounted, and floor mounted units.  They make single and multi-split systems that can handle as many as 5 rooms. 

• Senville, founded in 2005, make mini-split and multi-zone air conditioners and heat pumps. Their headquarters is located in Montreal, Quebec. 

• Daikin is an air conditioner company that was founded in 1924, originally focusing on electrical equipment. They are makers of residential and commercial air conditioner units which also function as heat pumps. They are located in Osaka, Japan. 

• MrCool makes heat pumps, air handlers, and air conditioning systems in a number of configurations. They have a number of mini-split heat pump series: DIY (known for its easy installation), Advantage, E-Star, Hyper Heat, and Olympus Multi.