The most efficient split systems for a cold climate

How this ranking works

The Zoned Energy Rating Label gives each model a cooling and a heating star rating for the hot, average and cold zones. We rank on cold-zone heating stars, because that is where a cold-climate unit uses most of its power. Only reverse cycle wall splits are included.

Cold-zone heating ratings are low across the board because the label tests heating against long, cold winters where every heat pump works harder. On the register, only 16 of the 1,480 models reach 3.5 stars and 195 reach 3. The most common rating is 2.

Why you should only compare stars within one size

As with cooling, bigger units rate lower, and at the larger sizes the ratings bunch up so tightly that stars barely separate the field.

Premium brands do better here than in the cooling rankings. At 3.5 kW, 28 of the 51 top-rated models are Mitsubishi Electric. At 5 kW, six of the seven are Daikin. At 8 kW the ranking tells you almost nothing, since 121 of 147 models share the top score.

What else matters for heating in a cold climate

• Heating output in kW. Size a cold-climate unit on the heating figure and ask how the output holds up on a frosty morning. Every unit delivers less than its rated output when it's very cold outside.
• Defrost. In frosty areas the outdoor unit periodically defrosts, and heating pauses. Ask the installer how the model you're considering handles it.
• Where the warm air goes. Warm air rises, so a high-wall unit in a room with high ceilings heats the cornices first. A floor console can suit a cold room better.
• Size and insulation. Use the size calculator and fix draughts before you buy a bigger unit.

Compare running costs against your current heater with the running cost calculator, then get up to three local quotes for the model you've shortlisted.