Should you leave your commercial heating on overnight in winter?

November 12 2025

Cognique

 

Robust commercial heating keeps things warm and cosy on even the coldest winter’s day. An important question is: should you leave your heating on overnight?

Should you leave your heating on overnight?

The simple answer is: probably not! Whilst it might be tempting to keep your heating running at a low level overnight so it doesn’t take as long to heat to optimum temperatures the next day, this is neither an efficient nor cost-effective solution.

1. Timed heating

For maximum efficiency, your heating should be set to come on at certain times. Ideally, your thermostat should be set between 18 and 21°C. As long as it comes on several times a day, it should maintain a comfortable interior temperature – and you can always let it run longer on especially cold days.

Timed heating keeps your building comfortably warm without overrunning your heating and increasing your heating bill.

2. Prevent frozen pipes

Setting your heating to turn on periodically using a timed thermostat is also essential for preventing pipes from freezing.

In cold weather, you need to make sure that warm water is regularly flowing through your heating system. Without this, there is a risk of the water in your pipes freezing and expanding, causing burst pipes and catastrophic damage.

3. Correctly set up your boiler

Commercial heating systems are generally controlled by a boiler. As well as setting your thermostat to the correct temperature, it’s important your boiler is set to heat the water in your heating system to the right temperature too.

In this case, it’s best to ensure your boiler’s temperature is set no higher than it needs to be. The general recommendation is to heat your boiler to around 60°C for hot water, and 70°C for heating.

4. Save money

Whilst you might think it’s cheaper to leave your heating on low over night, it is actually more cost effective (and energy efficient) to run your heating periodically in the day.

Using a smart thermostat, you can set the heating to come on just before staff start arriving in the morning.

5. Save energy

Energy bills are on the rise – and the winter can easily become an expensive time of year if you’re running your heating too hard.

There are several things you can do to save money on your heating:

  • Book your heating system in for regular maintenance by qualified heating professionals (like us) to keep it running at optimum levels.
  • If your heating system is old and power-hungry, consider replacing it with a more modern and efficient system.
  • If you operate from a building with high ceilings, consider installing destratification fans to reduce heat loss and improve heating efficiency.

Share this article

Whether your heating system needs replacing or a bit of winter maintenance, we can help.

Free Site SurveyContact Us