Ducts, or the lack of them

A heat pump can be ducted, blowing warm air through a network of metal tubes inside your walls and ceilings. Or it can be ductless, sending warm air directly out of a small head mounted on a wall or recessed in a ceiling. Both are heat pumps. The choice between them is mostly about your house.

The case for ducts

If you already have ductwork that is in reasonable condition, the conversion to a heat pump is often the smoothest path. A ducted heat pump replaces the furnace at the basement or attic end of the duct system and uses the existing tubes to deliver warm or cool air to the rooms. The thermostat looks like the one you replaced. The vents look the same. The system runs quieter than what you are used to, partly because heat pumps modulate rather than cycle.

The catch is that a lot of existing ductwork is not actually in reasonable condition. It leaks at the seams, runs through unconditioned spaces, and was sized for a furnace that ran at a much higher output than a heat pump needs. A good contractor will inspect the ducts and seal them as part of the install. A bad contractor will hook the new equipment to leaky ducts and call it done. The performance difference between those two installs is large.

The case against ducts, which is really the case for ductless

If your house has no ducts, or has ducts only in part of it, ductless is a serious option, and often the better one. Each ductless head is a small, independently controlled indoor unit. One outdoor compressor can serve up to six or eight heads. Each room becomes its own climate zone. You heat the bedroom at night and the living room during the day. You do not heat the spare bedroom unless someone is in it. The savings from zoning alone are real.

Ductless installs are also less invasive. The refrigerant lines run through small wall penetrations rather than soffits and chases. The disruption to the house is measured in days rather than weeks. The aesthetic question (we cover that in on the matter of looks) has gotten much better. The recessed and floor-mounted units, in particular, are no longer something to hide.

The middle path

Some homes are best served by a mix. A central ducted unit for the main living space, where ductwork is already in place, paired with one or two ductless heads in additions, basements, or finished attics where the ducts never reached. This is the install pattern that good contractors land on most often in older homes. It uses what is already there and adds only what is needed.

What it asks of the homeowner is a willingness to think about the house room by room rather than as a single block to heat. That shift in thinking is one of the quiet benefits of moving to a heat pump. The system encourages you to use the house the way you actually live in it.

If you only remember one thing. Ducted and ductless are both heat pumps. Whoever tells you that one is the real one and the other is a compromise is selling you the one they prefer to install.