Heat pumps in TaupōSized for the coldest mornings, not the average.

Why sizing matters more in Taupō

Heat pump output falls as the outdoor air cools. Mitsubishi Electric NZ gives an example: a unit rated at 5.6 kW for heating is likely to deliver about 4.76 kW at 0 degrees. It says an undersized unit will defrost at the minimum intervals and may never reach the temperature you've set.

So read the label past the headline number. EECA says the heating capacity at 2 degrees should be at least as high as the 7 degree figure wherever nights get that cold, and BRANZ describes a third rating, H3, for output at -7 degrees. Ask the installer for it. Consumer NZ suggests people in near-freezing areas look for a better low temperature performance score in its test results.

Mitsubishi Electric NZ also says places with sub-zero winters need a larger heat pump or one of its upgraded models. A specialist who installs heat pumps in frosty inland towns will size from your rooms, your insulation and local lows. BRANZ is plain that a heat pump doesn't replace good insulation.

Placing the outdoor unit for frost and fog

Mitsubishi Electric NZ says the outdoor unit's location is essential for low temperature performance, and that the more moisture in the air, the more freezes on the coil. With 50 fog days a year, give it open air. Not under a deck or beneath the house, where Mitsubishi says units can create their own microclimate.

BRANZ wants at least 100 mm of clearance off the ground and suggests the warmest wall, such as one facing north or west. Near Wairākei, ask about corrosion protection for geothermal air as well.

The jobs that come up most in Taupō

Heat pump installation. First units and replacements both turn on the sizing above. Our heat pump installation page covers the rest of the job, from the pipe run to the electrician's paperwork.

Heating the whole house. Through a long cold winter the bedrooms matter too. A ducted heat pump or a multi-room heat pump is the usual answer. BRANZ warns that ducts running through uninsulated space can lose more than 30% of the heating energy, so duct design counts.

Moving off wood. If you're thinking of swapping a burner for a heat pump, Taupō District Council named heat pumps among the low-emission options. Size it to carry the coldest mornings.

Damp. With the Lakes district above the national damp figure, heating alone doesn't always fix it. Our home ventilation page explains what does.