How do Mini Splits Work in Cold Weather?

Mini splits are a type of air conditioner and heating system known for their ability to effectively control the climate within a space, despite extreme temperature changes outside. Unlike traditional systems, which can struggle when outdoor temperatures hit extremely high or low points, mini splits are designed to eject and absorb heat even during cold weather.
​When the mercury drops, the performance and efficiency of standard HVAC systems often decline. This is not typically as perceptible during the hot summer months but becomes dramatically apparent with dramatic drops in temperature. However, many mini splits are equipped to handle these drastically low temperatures. Through advanced technology, they continue to function by extracting heat from the outside air, even when it feels frigidly cold. This ability to maintain operation without a significant loss in efficiency is what makes mini splits so valuable in extreme conditions.

Mini Split Temperature Ranges

When the weather turns cold, many homeowners wonder how well their mini splits will provide heat. The ability of these systems to effectively heat your home largely depends on the type of unit and how it's designed. Some mini splits are designed specifically for low temperatures, capable of operating efficiently in cold climates throughout the year without the need for a supplemental heater.
Units vary from economy-level to mid-level and higher-end models, with each offering different levels of heating efficiency. For instance, while economy-level models may struggle to keep up when the ambient temperature drops severely, mid-level and advanced systems use more robust technology to provide warm, consistent air. These higher-end models maintain their efficiency even when the weather is frigid, making them suitable for places that experience moderate to low temperatures for extended periods.
​From personal experience, upgrading to a higher-quality mini split transformed my winters, turning what used to be a chilly ordeal into a comfortable season, even as the temperature outside dipped below freezing.

Higher-Heat Mini Splits for Extreme Cold

When you live in an area that experiences frigid winters, you should consider a heat pump mini split system. These systems are designed to work efficiently even when the temperature dips below zero. One important factor to look at is the HSPF (Heating Seasonal Performance Factor) rating. This rating shows how well a system can perform in cold conditions.
Some brands have designed mini split systems specifically for cold weather solutions. These systems have higher heating capabilities and perform with greater efficiency in extremely cold temperatures. For example, two brands that offer these cold weather solutions are well-known for their advanced technology and reliable performance. When the temperature drops, these systems maintain their efficiency, ensuring your home stays warm and comfortable throughout the winter.  The two brands below offer great cold weather mini split solutions.

• Mitsubishi Hyper-Heating
• LGRED High Heating Capacity​

Outdoor Unit Installation in Cold Weather Areas

Mini splits are efficient heating systems even in cold weather. They use an outdoor condenser to absorb heat from the air and transfer it inside. The system operates by circulating refrigerant between the indoor and outdoor units. Even when it’s winter, mini splits can extract heat from the air and warm your room.
​Installing the outdoor unit correctly in cold weather is crucial. Ensure it has adequate clearance from walls and overhangs to prevent snow and ice from building up. It's best to elevate the unit high enough off the ground to avoid anticipated snowfall coverage. This positioning helps the unit operate correctly and greatly impacts its efficiency. Additionally, a shelter or roof over the unit can affect its performance well by protecting it from harsh elements. Proper spacing and positioning are key to ensuring your system operates efficiently and reliably all winter long.

Improving Heating Function in Cold Climates

Running a mini split in extremely cold conditions can be challenging, but it's essential to maintain optimal performance. Mini splits use a special mode called defrost mode to remove frost from the outdoor coil. This mode periodically switches on and melts the ice buildup. The dripping water then flows into a drain pan, preventing the fan blades and fins from freezing and expanding or cracking.
To further prevent damage and ensure the mini split works effectively, a Drain Pan Heater is strongly recommended. This heater plugs directly into the control board of the outdoor condenser and turns on automatically when subfreezing temperatures are detected. It helps escape frozen water and reduces the chance of ice buildup thick enough to cause another problem or the need for repairs, which can cost up to $1,000. Different brands and models may have varying features, but using these tips can help keep your mini split in top condition.

Improving Cooling Function in Cold Climates

When relying on a mini split system to cool a server room or a busy kitchen in cold weather, it's critical to ensure the system continues to function year round. In extreme cold conditions, using the appropriate system is key.
From my experience, when the cold outside air is moving too quickly, it can cause the system to fail altogether. Wind baffles can alleviate this problem by blocking the wind from blowing directly on the condenser unit's fan. This helps control the air flow across the coil.
Be aware that selecting the right mini split system and properly installing wind baffles can significantly improve the performance of your system in cold weather, ensuring it operates efficiently and reliably even when temperatures drop.

FAQ'S

Q. How cold is too cold for a mini split?

​Mini splits work efficiently in cold climates but can struggle below 20°F and 0°F, decreasing efficiency and requiring longer run times. A base pan heater can help by preventing ice buildup. While generally reliable, very cold temperatures might necessitate supplemental heat to maintain indoor comfort.

Q. Do mini splits freeze in the winter?

​In freezing temperatures, mini-split systems can develop frost and ice on the condenser coil and other coils due to moisture. To prevent this, they have a defrost mode that melts the ice and keeps the system running efficiently.

Q. What are the disadvantages of a mini split system?

​Mini splits work in cold weather by using inverter technology to adjust compressor speed for efficient heating. They use heat pumps to draw outside air without needing ductwork, ensuring energy savings and comfort in low temperatures. However, they have a high cost, limited cooling capacity for large spaces, and may struggle in extreme cold.

Q. Should I turn off my mini split in cold weather?

​It's best to keep your mini split on in cold weather. Turning it off can lead to higher energy costs and less comfort purposes. Homeowners should let it run to maintain warmth and save dollars over time. This is the best advice for consistent heating and efficiency.