Heat Pump Holiday Settings: What to Do When You Go Away in Winter

Don’t switch your heat pump off at the isolator when you go away in winter. Use the holiday or away mode on your controller, or turn the room temperature down moderately, and keep the system powered so its frost protection still works. Before you leave, check the pressure and look for fault codes. Set the heating to resume a day before you get home, because heat pumps warm a house slowly.

The suitcases are by the door, the taxi’s booked, and then you stop and wonder what to do with the heating.

With a boiler, most people either leave it on low or turn it off and hope for the best. A heat pump needs a bit more thought, but not much. The main aim is to keep the system safe from frost without paying to heat a house nobody’s in.

Why you shouldn’t just switch it off

It’s tempting to turn everything off at the isolator and walk away. In summer that’s fairly harmless. In winter it’s a risk.

Most of a heat pump’s frost protection depends on power. When temperatures drop, the controller can run the circulation pump to keep water moving and bring the heating on if the house gets too cold. If you’ve isolated the unit, none of that can happen. Some units also keep small heaters running to protect parts of the system, and your manual will tell you whether yours does.

There’s a second reason. A house that’s allowed to get properly cold is more likely to develop condensation and damp, and it takes a long time to recover. Heat pumps are efficient because they run gently and steadily. A big swing from cold to warm isn’t their strength.

So for a winter absence, keep the power on and change the settings instead.

Use holiday mode, if your controller has one

Most controllers have a holiday or away mode. You set the dates, and the system drops to a lower temperature (and often pauses hot water) until the end date, then goes back to normal. It’s the simplest and safest way to do it, and it means you can’t forget to turn the heating back on.

Check your manual or controller menu for what yours does. Some versions only affect hot water, some only affect heating, and the wording varies between manufacturers.

If you don’t have a holiday mode, lower the room thermostat setting, or change your schedule so the system only runs to a low target.

How low should you set it?

There’s no single right number, because it depends on how well insulated your home is and what the weather does while you’re away.

As a rough guide:

• A weekend away: leave things as they are, or drop the temperature by a degree or two. The savings from a deep setback over a couple of days are small, and the house has to climb back up afterwards.

• A week or two: a moderate setback is sensible. Many people choose somewhere around 12 to 15°C, so the house stays well clear of freezing without heating it for nobody.

• Longer than that: talk to your installer. A month or more in a cold snap is a different situation, and the right settings depend on your system.

Please don’t go all the way down to the bare frost-protection level unless your installer says it’s right for your system. A very cold house isn’t just a freezing risk. It can also mean damp walls and mould by the time you’re back.

If you’re not sure what your controller’s frost protection actually does, ask your installer before the cold weather arrives, not while you’re abroad.

What to do with hot water

Hot water is usually the first thing to switch off in holiday mode, and that’s fine for a week or two. A cylinder that isn’t being heated for a long time doesn’t need much from you while you’re away.

When you get home, give it time to reheat before you need a lot of hot water. If you’ve been away for a week or more, run the hot taps and showers for a couple of minutes to flush through stale water. That’s sensible hygiene after any long absence, not just a heat pump thing.

A short checklist before you leave

Spend ten minutes on this the day before you go:

• Check the pressure. It should be in your normal range. If it’s already low or has been dropping, sort it before you leave. Our guide on what to check before calling an engineer explains why topping up repeatedly isn’t a fix.

• Look for fault codes. If one’s showing, don’t leave it. Our guide to common heat pump fault codes explains what the main categories mean.

• Check the date and time on the controller. A wrong clock can throw out your schedule and holiday dates.

• Clear the area around the outdoor unit. Leaves and debris can block airflow. If you want to understand what’s normal for water and ice around the unit, our guide to heat pump condensate drainage covers it.

• Leave radiator valves and zones as they are. Closing them all down can cause problems of its own.

• Photograph your settings. If something resets while you’re away, you’ll know what to put back.

• Tell someone with a key. A friend or neighbour who can look in during a cold snap is worth having. Ask them to check the house is warm and nothing looks wrong, not to touch the heat pump itself.

Our winter maintenance checklist goes into more detail if you’d like a fuller pre-winter check.

What if the power goes off while you’re away?

This is the scenario most people don’t think about. If there’s a long power cut in a hard frost, the system can’t run its frost protection, and you won’t know about it until someone tells you.

How worried you should be depends on your system. If your water pipework runs outdoors and isn’t protected with glycol or freeze-protection valves, the risk is higher. Our article on what happens to a heat pump in a power cut explains the difference between system types and what to ask your installer.

If your controller or app can send alerts when it loses connection, switch them on. It won’t prevent a problem, but it can mean a neighbour looks in sooner.

Plan your return

This is the step people miss. A heat pump warms a house slowly. If you walk in on a cold evening and turn everything up, you’ll wait a long time for the house to warm, and a very high flow temperature rarely speeds things up. It usually just costs more.

Instead:

• Set the holiday mode to end a day before you arrive, or schedule the heating to resume early.

• If you can’t do that, expect the house to take several hours to feel properly warm, and don’t crank the settings up in frustration.

• Let the cylinder reheat before running a long bath.

What to check when you get home

Walk through this before you settle in:

1. Look at the controller. Is it on, showing the right time, and are your settings intact?

2. Check for fault codes. Photograph any code before you reset anything.

3. Check the system pressure. It should be close to where you left it. A big drop may point to a leak.

4. Check the breakers. If one has tripped, reset it once. If it trips again, stop, and read our guide on why a heat pump keeps tripping the breaker.

5. Look around the outdoor unit. Check for ice, damage or standing water that shouldn’t be there.

6. Give it time. Watch how it behaves over the first few hours. If it keeps stopping and starting, our guide on why a heat pump keeps turning off explains how to tell normal cycling from a real problem.

When to get help

Most of the time you’ll walk in, the house will be cool but fine, and it will warm up by the evening.

Get help if the heat pump shows a fault that won’t clear, the heating or hot water won’t start, pressure has dropped, or settings have vanished.

Our Fix My Heat Pump service is remote. We go through your fault codes, controller settings, pressure and how the system is behaving, to work out what’s wrong and what to do next. We’re independent, so there’s no incentive to sell you a repair. We can’t fix frozen pipework or do electrical work over a video call, but we can help you work out whether it’s a settings issue, a hydraulic problem or something that needs an engineer on site.

Frequently asked questions

Should I turn my heat pump off when I go on holiday in winter?

Not at the isolator. Switching off the power also switches off the frost protection and any heaters that protect the system. Use holiday mode or a lower temperature setting instead.

What temperature should I leave my heating at when I’m away?

It depends on your home. For a week or two, many people choose somewhere around 12 to 15°C. For longer, or if the house is poorly insulated, ask your installer.

What is holiday mode on a heat pump?

It’s a setting that lowers the heating, and often pauses hot water, for dates you choose. It then returns to normal on the end date. Names and options vary between controllers, so check your manual.

Will my heat pump freeze if I leave it on while I’m away?

If it’s powered and set sensibly, its frost protection should look after it. The bigger risk is a long power cut in very cold weather, which is why it’s worth asking your installer how your system is protected.

Is it worth turning the heating down much for a short break?

Often not. For a weekend, the savings are usually small, and the house has to recover afterwards. For longer trips, a moderate setback makes more sense.

Came home to a heat pump problem?

Tell us what you’re seeing, and we’ll help you work out what to check first.

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