ductless

Ductless mini-split units are a viable alternative to ducted HVAC systems, offering superior energy efficiency and a simpler installation.

Many mini-splits also have a reversible design, which means they can operate as air conditioners during summer and as heat pumps during winter. This means you’re combining two mechanical systems into one, saving on both equipment purchases and installation costs.

As you might imagine from their name, mini-splits are composed of an indoor unit and an outdoor unit, which are connected by insulated refrigerant lines.

Mini-splits are called “ductless” because they don’t need air ducts like traditional HVAC installations, and “split” because they are divided into an indoor and outdoor unit.

The indoor unit circulates air from the room where you install it, lowering or raising its temperature according to the thermostat settings.

Here we will discuss the main advantages of mini-split units when compared with traditional window-type air conditioners and ducted systems. We will also review some of the best mini-split brands available in now for the upcoming year.

Pro Tip: Before upgrading your space heating or air conditioning system, make sure your home is properly insulated and seal any air leaks. This will reduce the workload on the new HVAC equipment, and you will achieve even greater energy savings.

Understanding Energy Efficiency Metrics for Mini-Split Units

When purchasing any type of equipment, having a numerical value that describes energy efficiency is very useful.

For example, we look at the gas mileage value (MPG) when comparing different types of cars, to get an idea of their fuel consumption. In the case of mini-split units, there are two energy efficiency metrics we need to consider.

• The Seasonal Energy Efficiency Ratio or SEER describes the efficiency of a mini-split air conditioner.
• The Heating Seasonal Performance Factor of HSPF describes the efficiency of a mini-split heat pump.

A reversible mini-split capable of operating as either an air conditioner or a heat pump will have both metrics, a SEER for cooling mode and an HSPF for heating mode.

In both cases, a higher efficiency rating translates into less power consumption and lower electricity bills. Understanding these metrics is important before comparing mini-splits from different manufacturers.

The SEER can be defined as the average cooling output per unit of electricity consumed, during the season when air conditioning is typically used.

The cooling output is measured in British Thermal Units (BTU), while the electricity input is measured in watt-hours. This means you can estimate power consumption by dividing the rated cooling output (BTU/hour) by the SEER value.

• As a quick example, consider a mini-split air conditioner with a rated cooling capacity of 12,000 BTU/hour and SEER 24 efficiency.
• Dividing both values, you get an average power consumption of 500 W or 0.5 kW.

Assuming you use this air conditioner for 2,000 hours in a year, you can expect an electricity consumption of around 1,000 kWh. At an electricity tariff of 16 cents/kWh, this adds $160 to your annual power bills.

You should look for the highest possible SEER rating, regardless of the mini-split brand since high efficiency can save you hundreds of dollars in cooling over time.

If you repeat the calculation with the same cooling capacity (12,000 BTU/h) but a lower SEER rating of 13, the annual cooling cost increases to nearly $300.

The HSPF used by heat pumps is a similar concept: the average heating output per unit of electricity consumed. In the case of reversible mini-split units, you will notice that the HSPF for heat pump mode is typically lower than the SEER for air conditioning mode.

While the most efficient mini-split air conditioners reach a SEER of over 30, the most efficient mini-split heat pumps offer an HSPF of around 13-14. This happens because cold weather limits the efficiency of the refrigeration compression cycle used by mini-splits.

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The 10 best ductless mini split heat pumps in single zone and multi-zone categories are listed below to provide you with the information to make the right buying decision. We won’t steer you wrong with our expert picks – these are outstanding systems you can customize to perfectly fit your requirements.

What else is here?

This mini split buying guide includes costs, features, pros and cons, and the installation/use that will give you the best return on investment (ROI) for each model.

First, we’ll give you some information on mini split heat pump systems. If you’re good to go on the what’s and why’s, then jump down to our top 10 ductless mini split system list and reviews. On the other hand, if you’re thinking through ductless mini split vs. standard split system heat pumps, the upfront information will be of use.

What is a Ductless Mini Split Heat Pump System?

A ductless mini split HVAC system includes two main component types. The first is the outdoor unit called a condensing unit. It contains the compressor which cycles refrigerant through the system to move heat from one location to another – either into or out of your living space.

The second type of equipment is one or more indoor air handlers. The air handlers are connected to the outdoor condenser by refrigerant lines, a power cable and a condensation drain line.

Mini Split Sizes: Outdoor condensing units are available in 9k to 60k BTUs. The one you choose will depend primarily on the amount of space you need to heat and cool but also the layout of your home, how well your home is insulated and your climate.

Single vs Multi-zone Systems: A single zone system, meaning it has one air handler, can be used in a single room, apartment, small home with an open floor plan, or a converted attic or garage. They are ideal for cottages and cabins too.

A multi-zone system, a system supporting two to eight air handlers, can be used to heat and cool an entire home or other building with clearly defined rooms/zones.

Did you know? Air handlers, the indoor units, are available in 9k to 30k BTUs.

Each indoor air handler is installed in a specific area or room, referred to as zones, and all handlers are connected to the outdoor unit. Each air handler can be independently controlled with a thermostat or remote. Your HVAC contractor can help you decide where to place the air handlers to provide the most effective and energy-efficient layout.

Can the total capacity of the air handlers/indoor units exceed the capacity of the condensing unit? Yes, it can, but it should not exceed it by more than about 15%. For example, if you need a 36,000 BTU condensing unit for a three-zone installation, the easiest choice would be three 12,000 BTU air handlers for a total of 36,000 BTU.

But if one of the zones is larger, installing a 15,000 BTU air handler (9% over capacity) or 18,000 BTU (16% over capacity) air handler in that zone would be acceptable. Just keep in mind that you’ll still only get 36,000 BTU of heating and cooling across the multiple zones.

This is where the thermostats for each zone come in very handy. Reduce the heating/cooling in a zone not being used, so you have sufficiently warm or air-conditioned air in occupied areas.

How a Ductless Mini Split System Works

A mini split provides heat, air conditioning, dehumidification, and the flow of fresh, filtered air.

When the mini split is in air conditioning mode, the air handler pulls the warm air from inside your home over cold evaporator coils where heat is absorbed by the refrigerant. The heated refrigerant is pumped outside where it disperses the heat. The cooled air is sent back into the living space.

When the system is in heating mode, the refrigerant absorbs heat from outside and brings it inside where it is released in the coil in the air handler. It is then blown into the room. Due to the thermodynamic properties of refrigerant, heat can be absorbed from the air in outside temperatures as low as 20 F below zero.

However, as the outside temperature sinks, your mini split heat pump will lose efficiency and effectiveness. Still, the physics of refrigerants are very impressive!

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The limits are off for ductless heating and cooling systems, as double-digit growth in installations for six years running demonstrates.

Mini split HVAC systems are no longer just for additions, rooms far from central heating that are too hot or too cold, or locations where installing or extending ductwork is impossible.

New technology and competitive costs are behind the growing number of applications including new construction.

This comprehensive ductless heating and cooling guide covers costs, system types, options, features, efficiency, pros and cons, and more.

Did you know?

Ductless mini split outdoor units are now being produced for cold climates. For example, the Fujitsu Halcyon XLTH Extra Low Temp system is an impressive 33 SEER ductless system that provides heating in temperatures as low as -5 degrees Fahrenheit.

Trane’s low-temperature 4MXW38 system offers 38 SEER/15 HSPF efficiency and 100% heating performance to -20F.

Haier America, Samsung, Friedrich, and several other brands have introduced cold climate ductless heat pumps. A base pan heater in these outdoor units allows condensate to drain without freezing.

How Much Does It Cost?

Mini split heat pumps cost higher than standard split systems, but significantly less than geothermal system costs.

Small, single-zone systems with complete installation start as low as $4,000. Large, complex systems can cost as much as $17,500 installed. Here are the average installed costs for three common system sizes. There’s more detail in various sections below.

• Single zone systems: 1 indoor unit (6,000-36,000 BTU): $4,000 to $8,000
• Average multi-zone systems: 2-4 indoor units (18,000-36,000 BTU total): $6,800-$13,500
• Large multi-zone systems: 4+ indoor units (up to 60,000 BTU total): $10,500-$18,500

Here’s a quick breakdown of mini split HVAC costs for equipment and installation:

• Outdoor unit cost: $1,000 to $6,500 (9K to 60K BTU)
• Indoor unit cost: $300 to $2,500 (6K to 36K BTU)
• Accessory package: $250-$2,500
• Ductless HVAC system installation (warrantied labor) cost: $2,500 to $5,500

The accessory package may include a line set, drain tubing, wiring, thermostat, remote control, additional refrigerant when indoor units are distant from the outdoor unit, condensate pan heater for cold climates and other equipment required for installation.

Did you know?

Knowing the technical terms will assist you when researching your options, shopping and discussing the project with an installer. In technical terms, outdoor units are also called condensers.

A condenser contains the compressor that circulates refrigerant and the condensing coil that disperses heat during an AC mode and collects heat in heating mode.

Indoor units are also called air handlers and evaporators, and there are several types (explained in the section of Indoor Unit Types below).

Pro Tip: You’ll spend less on equipment and installation when you choose one large outdoor unit that supports multiple indoor zones rather than several separate single-zone ductless systems. In a multi-zone system, the climate of each room or zone can be independently controlled for customized comfort.

Mini Split System Cost Factors

Ductless mini split system costs vary widely based on:

• Whether it is AC-only ($-$$$) or a heat pump ($$-$$$)
• Cost rises as energy efficiency goes up.
• Cost rises with the size of the outdoor unit, though again, one outdoor unit costs less than two outdoor units with the same cumulative capacity (one 48,000 BTU unit vs. two 24,000 BTU units, for example).
• The number, capacity and type of indoor units (single zone vs. multi-zone)
• Indoor units with variable-speed fans for better climate control cost 15% to 25% more.
• The complexity of the installation

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