Ductless Mini Split Systems: Which One Do I Need?

When acquiring a ductless mini split system, it is important to determine which one will meet your heating or cooling needs. Follow this quick guide to ensure you choose the best mini split heat pump or air conditioner for your space.

BTUs, or British Thermal Units, dictate the amount of area a mini split unit can cover. This is the measurement you will pay most attention to in combination with the square footage of your space. Rather than calculating the number yourself, consult this table to learn how many BTUs your mini split needs.

This table provides an approximate BTU measurement and does not substitute a professional estimate. A professional HVAC assessment will consider other factors like insulation, ceiling height, flooring, and windows. The condition of these factors can increase or decrease the BTU rating your mini split needs.

Depending on how you plan to use your mini split, different types and configurations will have certain benefits.

Primary or Supplementary?

If you intend to use your mini split as a primary source of heating and cooling, your BTU estimate should be as accurate as possible.

A mini split with too few BTUs won’t sufficiently cover an area, forcing overcompensation. This means that the unit will overwork itself endlessly to try to heat or cool the space. An overworking system wastes energy and drives up your energy bill.

Purchasing a mini split system with too high of a BTU rating is also unnecessarily expensive. Not only will the system use more energy than you need, but it will also make temperature control more difficult. If one of your goals is to save energy, a mini split system with an incorrect number of BTUs is counterproductive.

However, if you plan to use your mini split as a supplemental HVAC system, you can use less BTUs than the standard estimate.

Single or Multiple Rooms?

To heat or cool just a singular indoor room, you can use a single zone ductless mini split system. Single-zone mini splits consist of one outdoor condenser unit and one indoor air handling unit. Refrigerant lines connect them and transfer heat in or out of the building.

However, if you have multiple rooms that you need to heat or cool, opt for a multi-zone mini split system. These systems have one outdoor condenser which connects to multiple indoor units. This allows you to put one air handler in every room you need to cover.

Though a multi-zone system has one overall BTU rating, you can independently adjust the temperature controls for each air handler. This gives each room its own individual heating or cooling system.

Heat Pump, Air Conditioner, or Both?

Ductless mini split systems function as either air conditioners, heat pumps, or both simultaneously. Depending on your area’s climate, you may benefit from one type over the other.

Areas with warmer climates do not require as much heating, so opt for a ductless mini split air conditioner. In more extreme heat, the condenser will have to work harder and may have a shorter life span as a result. To mediate this, you may want to purchase a more powerful system.

Conversely, areas with colder climates benefit from the use of a ductless mini split heat pump. Recent advancements in refrigerants allow heat pumps to operate in freezing temperatures. But again, in places with extreme winters, consider purchasing a more robust heat pump unit.

Ductless mini split heating and cooling systems have both air conditioning condensers and heat pumps in their outdoor unit. These systems are more expensive, but they consolidate all your HVAC needs into one compact unit.

Placement

You can place mini split air handlers almost anywhere inside your space. Many have mounting capabilities on either the wall or ceiling.

Ceiling cassette mini splits mount to the ceiling to maximize floor and wall space. You can fit them over a bed or lounge area, or in the corner of a garage for the best ventilation. A panoramic sunroom with little wall space could also benefit from a ceiling cassette.

Wall mounted mini split air handlers protrude from the wall, but often have slim designs to keep them flush. Typically, you mount air handlers about 8 feet from the floor, but you can install them anywhere you have space. But installing them too high reduces their efficiency as it hinders even air distribution.

Some mini split air handlers can also sit on the floor, and if you have the space, this can be the most convenient option.

Maintenance

Like any other home amenity, mini split systems require routine maintenance. Keeping your system in top condition will ensure it lasts and saves the most energy possible. Before performing any maintenance, always turn off power to your system to prevent safety risks.

Make sure to dust all your units frequently and check the air filter every few months. If you find it is clogged or dirty, you can clean it or replace it with the help of an HVAC technician. Clean your outdoor condenser coils every three months as well, since debris and dirt can accumulate between them.

But above all, you should have an HVAC professional come out once a year to check and tune-up your mini split system. They will be able to assess any issues and advise you on how to get the most out of your ductless mini split.

Shop HomElectrical’s selection of ductless mini split systems to start efficiently heating and cooling your space today!