Mini-split
What it is
A ductless, mini-split air conditioner provides zoned cooling without the ductwork.
Some ductless air conditioners and heat pumps are configured as split systems and are commonly referred to as mini-splits or multi-splits.
Its parts
- Condenser
- Another form of heat pump is the ductless mini-split heat pump. These split-systems feature a small ground- or wall-mounted outdoor unit connected via refrigerant lines to one or more indoor wall- or ceiling-mounted units that heat and cool the space they are in without the use of ducts.
- A pump that moves refrigerant between the evaporator and the condenser to chill the indoor air.
- Compressor
- Ductless heat pumps generally have inverter-controlled, variable-speed compressors. Ducted systems can also have variable speed compressors, but single-speed compressors are more common in these more traditional units.
- Recently available central heat pump models with variable-speed compressor designs that better match refrigerant flow to load can save even more and are more effective at lower outside temperatures. Ductless mini-split heat pump models have been available for several years that use variable-refrigerant-flow technology and can heat at 100% capacity at outdoor temperatures as low as -5°F.
- There are two broad categories of compressors: positive displacement and dynamic.
- Inverter compressor
- Variable-capacity ASHP: An ASHP that has a compressor which can operate at different levels, depending on the capacity needed.
- Line set
- Condensing units are typically provided with sufficient charge to accommodate 15–25 ft of refrigerant tubing. The line sets and indoor coil must be purged with nitrogen and evacuated to 240 microns of mercury and held for 10 minutes prior to opening service valves.
- Evaporator coil
- Evaporator coil means a component of a central air conditioner that is designed to absorb heat from an enclosed space and transfer the heat to a refrigerant.
- Air filter
- Most filters are designed to filter either particles or gases.
- Furnace and HVAC filters work to filter the air only when the system is operating.
Related pages
- Glossary: Mini-split
Its entry, and the guide's pages that use it.
- Ductless mini-splits
Ductless cooling and heating for homes and rooms without ducts
Sources
- U.S. Department of Energy. Energy Saver 101: Home Cooling.
- U.S. Department of Energy. Consumer Central Air Conditioners and Heat Pumps.
- U.S. Department of Energy. Traditional Split Heat Pumps.
- U.S. Department of Energy. Ductless Mini-Split Heat Pumps.
- ASHRAE. ASHRAE Handbook—Compressors.
- Natural Resources Canada. Air-Source Heat Pump Sizing and Selection Guide.
- U.S. Department of Energy. Measure Guideline: Air Conditioner Diagnostics, Maintenance, and Replacement (DOE Building America).
- Code of Federal Regulations. 16 CFR Part 305 Energy Labeling Rule.
- U.S. EPA. Guide to Air Cleaners in the Home.
- U.S. Department of Energy. HVAC Programmable Thermostats.