UPDATED on July 20, 2018, with new information from Carrier.
Mitsubishi and Fujitsu sell air-source heat pumps (ductless minisplits and ducted minisplits) that work well in cold climates. Many GBA readers report that these appliances are providing dependable space heating in climates as cold as Minnesota, Vermont, Maine, and Quebec, where temperatures drop to -20°F or colder.
Traditionally, U.S. manufacturers of air-source heat pumps have favored ducted units over ductless units. Most air-source heat pumps sold by Bryant, Carrier, Lennox, and Trane, for example, are designed to be hooked up to forced-air ductwork, just like a typical furnace.
Here at GBA, we often advise readers that ductless minisplits are a good way to heat and cool a compact well-insulated house. That said, ductless minisplits don’t work as well for large, spread-out homes or for homeowners who want uniform heating and cooling in every room, even when doors are kept closed.
Most U.S. homes have forced-air HVAC systems — that is, systems that distribute heat and cooling through ducts. Some GBA readers wonder, “Are there any cold-climate heat pumps that can be hooked up to conventional forced-air ductwork — the type of ductwork found in a typical American house?” We’ll do our best to answer that question.
Note that there is always an energy penalty associated with any heating or cooling equipment connected to ductwork. Equipment connected to ducts will never be as efficient as the best ductless equipment, because it takes a substantial amount of electricity to push air through ducts.
Japanese manufacturers of ductless minisplits also manufacture ducted minisplits. Even though these units are designed to be connected with ductwork, they generally can’t be connected to the type of forced-air ductwork installed in a typical American house.
Most ducted minisplit systems lack the type of powerful blower…