It’s one of the most common questions we hear once the first cold mornings arrive in Bristol and Bath, and everyone seems to have a neighbour who swears by keeping the heating on low all day. For most homes with a gas boiler, though, using a timer to heat the house only when you need it uses less energy overall. There are a few exceptions, and a boiler that’s had regular boiler servicing will run more efficiently whichever approach you choose.
Where the “always on” idea comes from
The theory goes that a cold house takes so much energy to warm back up that you’d be better off never letting it cool down. It sounds logical, and it’s true that the boiler works hard for the first part of a heating period.
The catch is that your home loses heat all the time, and it loses it faster the warmer it is inside compared with outside. A house kept at 19°C all day is leaking heat at full rate for every hour, even when nobody is there. A house that cools while you’re at work leaks heat more slowly as it cools, so there’s less to replace.
When keeping heat on low can be the better choice
If someone is home all day
If you work from home, have young children or care for someone who needs a steady temperature, there’s little time when the heating would be off anyway. A steady, moderate setting may simply be more comfortable.
If damp is a problem
Some older properties struggle with condensation and mould when they’re left to get very cold. Gentle background heat, combined with good ventilation, can help. Opening trickle vents and using extractor fans matters just as much.
During a hard frost
If temperatures drop well below freezing while you’re out, leaving the heating on low or using frost protection helps protect pipes, especially in lofts and on outside walls.
If you have a heat pump
Heat pumps work best running steadily at a lower flow temperature, so the advice for gas boilers doesn’t apply. Follow the guidance from whoever installed it.
Try it yourself
If you’re not convinced, run a simple test. Take a gas meter reading, then use one method for a week, such as timed heating morning and evening. Take another reading and switch to steady low heat for the following week. The weather will vary, so it’s not perfect, but it gives you a real feel for how your own home behaves.
Bristol and Bath homes: why the building matters
Housing across the area is varied. Georgian stone townhouses in Bath and Clifton have thick walls that warm slowly and hold heat for a long time. Victorian terraces in places like Totterdown and Easton often have solid brick walls and can feel draughty. Newer homes on the edges of the city are usually better insulated and hold warmth well after the boiler switches off.
In practice, a well-insulated modern home suits timed heating particularly well. Heavier stone buildings may benefit from a longer, gentler heating period rather than short blasts.
Getting the most from your controls
- Set the timer to come on about 30 minutes before you get up or get home
- Turn the room thermostat down one degree at a time to find your comfortable minimum
- Use thermostatic radiator valves to keep spare rooms cooler
- Keep the radiator in the room with the main thermostat fully open
Frequently asked questions
Does turning the heating on and off damage the boiler?
Normal timed heating, coming on in the morning and evening, is exactly what boilers are designed for. What can cause wear is a boiler switching on and off every few minutes, known as short cycling, which usually points to a fault or a boiler that’s too big for the home. An engineer can check this during a service.
What thermostat setting should I use in winter?
Many households are comfortable somewhere between 18°C and 21°C. Start at the lower end and increase it a degree at a time until it feels right. Anyone elderly, unwell or very young may need a warmer home, so set the thermostat for whoever is most vulnerable in the house.
Is it worth leaving the heating on low while I’m on holiday?
In winter, yes. Leaving the heating on a low setting or frost protection while you’re away helps stop pipes freezing and bursting while the property is empty. You don’t need the house warm, just warm enough to keep pipes above freezing, so a low thermostat setting is usually enough.
Want your heating running efficiently this winter?
If your heating seems slow to warm up or your controls aren’t doing what you expect, give us a call on 01275 400 687 or drop us a message and we’ll book a service and check your system is set up properly.