Ductless, Mini-Splits & Heat Pumps

What is a Ductless Mini-Split?

Gas or electric furnaces that force heated air through a series of ducts, are the most common type of heating system in the USA. These typically come with high energy and CO2 costs and homes that need cooling often need to have a second unit dedicated to that purpose. As the move to electrify and conserve our energy consumption has become more popular, ductless mini-splits have emerged as a flexible and cost effective solution that works well for most homes.

A ductless mini-split is a small, wall-mounted air handling unit that connects to an outside heat pump through a conduit line that houses both the power to the unit and the refrigerant coil that delivers the heat energy. Since the conduit line often only requires a small hole through drywall to the outside, it is often much easier to install ductless mini-split systems than traditional ducted heating systems. Additionally, mini-splits can handle heating and cooling within the same unit.

Because heat pumps draw in heat energy from the ambient air around them, drawing only a fraction of their energy from the grid, they are much more energy efficient than most heating/cooling systems. This can result in significant cost savings as well as a reduction in reliance on fossil fuels and grid energy.

What are the Pros and Cons of a Mini-Split System?

Con: Aesthetics

The main drawback of a mini-split system is the look of the air handler. While it is compact and designed to be as unobtrusive as possible, it doesn’t have the hidden, built-in look of a ducted air system. However, because of this, mini-splits also have added flexibility in terms of their location within your home.

Pro: Zone-Specific Temperature Control

Multiple mini-splits can control different zones in different areas of a house – keeping the bedrooms cool and the living spaces cozy is as easy as setting each unit to its own temperature. Many modern mini-split units also come with remote controls, making it simple and fast to adjust the temperature in any space.

Pro: Minimal Heat Loss

In addition to the energy savings of the heat pump unit, since there is no air flowing through a long series of ductwork, heat energy loss for mini-split units is minimal. Ducted heating systems can have up to a 30% heat loss just during the transfer of air through the ducts.

Pro: Easy Installation

As mentioned above, because just a single small hole is required for the conduit line to the wall-mounted air unit, installation can be very quick and easy depending on the location in your home.

Con: Upfront Cost

With whole-home heating and cooling in the $3,000-$5,000 range for ductless heat pumps, the upfront cost is about 30-50% higher than traditional ducted systems, not including installation. However because much less energy is required to run the units over time, the total cost of ownership is often much lower over time.

Pro: Rebates & Incentives

But there’s good news! Many local governments and utilities are offering incentives that range from $300 to $1,800 towards the cost of a heat pump or mini-split unit. This can bring the upfront cost down to comparable levels for a traditional heating system.

Pro: Continuous Heating/Cooling

Many ducted air systems are constantly turning off and on, to maintain a consistent temperature in your home. Mini-split systems are most efficient when they are running continuously and are built to maintain a constant temperature.

How Does a Mini-Split System Work?

A mini-split system, or ductless heat pump, is a heating and cooling system that can run in two directions. In heating mode, the heat pump draws in air from around it where a refrigerant coil transfers the heat to a conduit, which then runs out to the air handling unit and heats the air as it blows into your home. In cooling mode, the warm air from inside your home is drawn back out to the outdoor unit, and transferred to the outside. A heat pump can work efficiently, even in winter, in most climates around the United States. 

How Much Does a Mini-Split Ductless Heat Pump Cost?

Costs for ductless AC or heat pump systems can vary widely. From around $799 for a DIY-ready single zone unit to over $5,000 for a multi-zone, wi-fi enabled unit with a smartphone app.

While ductless heat pumps are simple enough for a skilled DIY homeowner, most units will require professional installation.

Sizing Your Mini-Split Ductless Heat Pump

Correctly sizing your unit to your home’s square footage is important to get the maximum benefit and efficiency.

12,000 btu units are typically 1-zone mini-split systems, while 36,000+ btu units can handle up to 4 or 5 air handling units for multiple zones in your home.

Room Size (Sq. Ft.) Heat Pump Capacity (BTU)
100-350 sq. ft. 9,000
350-500 sq. ft. 12,000
500-700 sq. ft. 18,000
700-900 sq. ft. 24,000
900-1,100 sq. ft. 30,000
1,000+ sq. ft. 36,000

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