The one outdoor – multiple indoor heat pump

Most of us are accustomed to heat pumps, but we’re used to a heat pump with an associated outdoor unit designed to heat one room. Technology has now developed, with the availability of a single outdoor unit that works with multiple indoor heat pumps to heat the whole house. We found out more about this technology from Mitsubishi Electric. 

The heat pump has become a standard part of most New Zealand homes. However, in most houses the heat pump system installed has, until recently, been a simple split-system outdoor unit designed to work with one indoor unit to heat one room of the house.

If a homeowner wanted to heat a second room or area with a heat pump, another split-system unit would need to be installed, meaning the dwelling would need two outdoor units.

“What that has meant for many people is the addition of multiple units outside the home,” Mitsubishi Electric’s Trish Stenzel says. “In situations where people live in apartments or townhouses and in higher density areas, there isn’t always the space to accommodate multiple outdoor units.”

However, this simple split-system technology has now been surpassed with a superior offering in the multi-room heat pump system. “The multi-room system allows for the installation of a more powerful single outdoor unit connected to one or more indoor heat pump units.”

Multi-room heat pumps can be installed with a minimum of two indoor units at the outset, and retrofitted to connect to further indoor units over time as needs require. “Unlike single split-system technology, where additional units can’t be retrofitted, multi-roomsystems can have additional indoor units connected as and when required over time,” Trish says.

While multi-room systems may represent a higher investment at the beginning, over time they pay off in terms of the ability to cost effectively heat the whole home with multiple heat pumps in different rooms. “It also means smaller dwellings can enjoy the benefits of multiple heat pumps without the need to incorporate multiple associated outdoor units in small spaces.”

Compared to other whole-home heating systems such as ducted or underfloor heating, multi-room heat pumps offer a cost effective and energy efficient option, Trish says. “Central heating and radiator systems are great but they are designed only for heating. With a multi-room heat pump system, you get the best of both worlds; efficient heating in winter, and cooling in summer.

“Most ducted heating systems are designed to heat the whole home simultaneously so if you’re heating the lounge you’ll also be heating the bedrooms and other rooms at the same temperature at the same time. With a multi-room system, each unit is operated independently from the rest, allowing for only the rooms in use to be heated when required. You have flexibility in terms of being able to choose which rooms to heat and at what temperature.”

There are also various options to choose from in terms of the indoor units, allowing for customisation of each room. “You can choose from high wall units in different colours, recessable floor consoles or unobtrusive ducted models to truly reflect the interior design style and differing needs of different areas of the home.”

Depending on the capacity of the multi-room outdoor unit chosen, anywhere from two to eight internal units can be connected.

If you’re considering heating options for an existing home or a new build, make sure you visit Mitsubishi Electric on ArchiPro here to find out more about the benefits of multi-room heat pump technology.