Ductless mini-split systems in St. Paul, MN

How a ductless system works

A mini-split has an outdoor unit and one or more indoor units mounted on a wall or ceiling. Refrigerant lines connect them and carry heat out of the room in summer. Because most models are heat pumps, they reverse the process to heat the room in winter.

Installation needs only about a three-inch hole through the wall for the connecting lines. According to the Department of Energy's guide to ductless mini-split heat pumps, the outdoor unit can sit up to 50 feet from the indoor unit. Many models connect up to four indoor units to one outdoor unit. Most indoor units are about seven inches deep and mount high on a wall.

Comfort room by room

Each indoor unit is controlled on its own, so you heat or cool only the rooms you use. That makes a mini-split a good fit for an addition, a sunroom, a finished attic or a bedroom that never stays comfortable. The Department of Energy also lists homes heated by boilers, radiant floors or space heaters as good candidates. Those homes have no ducts for central air.

With no ducts, there is no energy lost along the way. The Department of Energy says duct losses can use more than 30% of the heating and cooling energy in a ducted system. It rates ductless units at 15.2 to 35 SEER2.

Each indoor unit has its own filter that catches dust, pollen and other particles. With no ductwork, there is nowhere for dust to collect between the unit and the room. If you want whole-home filtration, see our whole-home air purification options.

Mini-splits in a Minnesota winter

Not every mini-split is built for our winters. ENERGY STAR's ductless heating and cooling guide explains that cold-climate models are tested down to 5°F and keep working below that. On colder days, it recommends pairing the system with a backup heat source.

Before we recommend a system, we look at the space, how it is insulated and what heats it now. We size the mini-split for the room and plan the backup heat with you. If you are weighing a ducted system instead, read about our heat pump installation and service.

Installation, repair and upkeep

Krinkie's is a Daikin ComfortPro certified dealer, and we install Daikin single-zone and multi-zone ductless systems. Our technicians are certified, background-checked and drug-tested. We size and install the right system for the space, and we service it for years to come.

Mini-splits have trade-offs, and we will explain them up front. The Department of Energy lists a higher upfront cost and sensitivity to sizing and placement. Some homeowners also dislike the look of the indoor units, and condensate has to drain outdoors.

Clean the indoor filters when they look dirty or the filter light comes on, which ENERGY STAR recommends. Schedule professional cleaning and inspection at least once a year, or twice a year if the system both heats and cools. Krinkie's Club members get two tune-ups a year.

Safety: what to leave to us

Do not install, move or recharge a mini-split yourself. Federal rules under EPA Section 608 refrigerant management prohibit intentionally venting refrigerant during service or disposal. Our technicians are certified to handle refrigerant properly.

The outdoor unit also runs on its own high-voltage circuit. Do not open its electrical panel or try to replace parts inside it. If the unit smells like burning or trips its breaker more than once, turn it off and call 651-488-5555.

Many homes pair a mini-split with a gas furnace or boiler for backup heat. The CPSC's carbon monoxide safety guidance calls for CO alarms on every level and outside sleeping areas. If an alarm sounds, get everyone outside and call 911. If you smell gas, leave the house and call 911 or your gas utility from outside.

A mini-split may be right if

• A room has no ductwork
• One room is always too hot or too cold
• You’re finishing a basement, attic or addition
• You want to replace window units
• Your home has boiler or baseboard heat and no central air

Common questions

Sources

• U.S. Department of Energy — Ductless mini-split heat pumps
• ENERGY STAR — Ductless heating and cooling
• Daikin Comfort — Ductless systems
• U.S. EPA — Section 608 of the Clean Air Act: stationary refrigeration and air conditioning
• U.S. Consumer Product Safety Commission — Carbon Monoxide Information Center