A heat pump is cheap to run when you use it well, and quietly expensive when you don’t. Most of that difference sits on the remote in your hand: the mode, the temperature, the fan and the timer. Get those four right and a frosty Canterbury morning costs a lot less to wake up in.
What settings should my heat pump be on in winter?
- Mode: heat, the sun symbol. Not auto, not dry.
- Temperature: 18 to 21°C.
- Fan: auto.
- Timer: on about 30 minutes before you get up or get home.
- Doors and curtains: closed.
What temperature should I set my heat pump to in winter?
Somewhere between 18 and 21°C. At 18°C or above you’re helping fight damp and mould, which matters in a New Zealand winter. Above 21, every extra degree pulls more power, and in the cold the unit works harder and defrosts more often for its trouble. Like your home on the warm side? Set the top of that range and leave it there.
What doesn’t work is cranking it to 28°C to warm the room faster. A heat pump isn’t a bar heater. It reaches a sensible setting just as quickly, and a sky-high target only leaves it running flat out chasing a temperature you never actually wanted. Pick the number you do want and walk away.
Overnight your body needs less. If you like a warm bedroom while you sleep, drop the setting to around 16 to 18°C instead of leaving it at the daytime figure.
→ Related: What a heat pump costs to run in a NZ winter
Should I leave my heat pump on all day?
For most Kiwi homes, no. Running it 24 hours a day in a typical house uses more energy, and plenty of that heat leaks out through the walls, windows and floor anyway. The pattern that works well is a couple of hours in the morning and a few in the evening, with the unit off while the house is empty.
Two exceptions.
Someone is home all day. If you’re home with a baby, working from home, or looking after an older person, a steady temperature through the day makes sense. Turn it off or down at bedtime.
Extreme cold. On the coldest days in places like Central Otago, starting the heating earlier, or leaving it on, can help the unit keep up instead of fighting to warm a freezing room from scratch.
Out for most of the day? Switch it off. On a sunny day the house holds some of the sun’s warmth, so the heat pump has less work to do when it starts again.
Does the timer actually save power?
The timer does more for your comfort and your bill than almost any other setting. Set it to come on about 30 minutes before you get up, and again about 30 minutes before you get home or before you lose the afternoon sun. You walk into a warm room, and the unit isn’t heating an empty house.
Most remotes have a daily timer. Some have a weekly timer with several start and stop times a day. Wi-fi control lets you change it from your phone, which helps on the days when plans change: smart wi-fi heat pumps.
What fan speed should I use?
Auto. The unit speeds the fan up to warm the room quickly, then slows it to hold the temperature.
A fixed low fan is quieter, which can suit a bedroom at night, but it stops the unit delivering its full heat and makes it less efficient. That means you pay more for less warmth. If the unit seems to struggle, check it isn’t stuck on a fixed low speed.
→ Related: Quietest heat pumps for NZ homes
What settings work best on frosty mornings?
When it’s frosty outside, the outdoor unit has to stop now and then to clear ice, and every pause is heat you’re not getting. You can cut how often that happens.
- Keep the setting at 21°C or below. Most heat pumps are sized on that basis, and a higher target makes the unit work harder and defrost more.
- Close off what you’re not using. On a ducted system, shut the zones for empty rooms so the unit only heats where you are.
- Stop flicking it on and off, and stop changing modes. Modern inverter units are most efficient holding a steady pace, and heavy on and off cycling plus frequent mode changes add wear over the years.
→ Related: Heat pumps that handle a proper NZ winter
How do I keep the heat in the room?
The settings only go so far if the warmth is escaping.
- Close external doors and windows while the heat pump runs.
- Close the doors to rooms you don’t use, so you only heat the space you’re in.
- Draw the curtains as the sun goes down. Thermal curtains help most.
- Block draughts under doors with a draught stopper.
- Spend time in the heated room. A heat pump uses the most energy getting a room up to temperature, so heating the room you actually live in gets the most from it.
How do I look after my heat pump over winter?
Clean the removable filters about once a month during winter. Vacuum them, or wash them in warm water and let them dry before you put them back. Clogged filters cut airflow and make the unit work harder. The outdoor unit and the yearly service are covered in heat pump servicing.
You’ll notice the unit pause for a few minutes on cold mornings. That’s the defrost cycle clearing frost from the outdoor unit, and it’s normal. Heat pump problems sorts what’s normal from what isn’t.
Should I book a service before winter?
If your heat pump struggled last winter, get it looked at before the frosts arrive. Find a heat pump servicer near you, or choose your town and filter by the job.
Not sure the old unit has another winter in it? Get a quote from an installer who’ll size it properly and set it up right.