Brits brace for another big freeze this week - boiler expert shares the common mistakes to avoid that can leave you in the cold 🥶

New data reveals February is officially one of the worst months for boiler breakdowns.

Almost a fifth of Brits [17%] struggled without heating and hot water this time last year due to boiler malfunctions - and with snow, ice and freezing rain set to hit Britain this weekend, heating systems could be under additional pressure. Also, over one in 10 Brits (11%) have already had to call out a gas engineer this month alone.

The study, which quizzed 2,000 UK adults found that boiler pressure issues emerged as a frequently reported problem.

Alarmingly, two-fifth of Brits [39%] admit they have never checked their boiler pressure, and one-in-10 confess to not even knowing what their boiler pressure is.

Meanwhile, one-in-five [20%] claim that their boiler pressure is currently too high or too low from the recommended level.

"After months of heavy use through December and January, minor boiler issues can escalate. Add in the winter cold snaps, and you have the ideal conditions for surprise breakdowns to peak," explains Ryan Gill, Lead Engineer at BOXT ).

Gill, shares his expert advice on how to tackle boiler pressure issues and avoid the common mistakes that can leave you in the cold.

1. Check your boiler pressure regularly

“Many people don’t realise that keeping an eye on boiler pressure is as important as regularly servicing your boiler,” says Ryan. “It’s the first thing to check if your heating or hot water stops working.”

To check the pressure, locate the gauge on the front of your boiler. Ideally, it should sit between 1 and 1.5 bars when the system is off.

A reading below 1 often means low pressure, which can prevent your boiler from working efficiently - or at all.

Common mistake to avoid: Never repressurise your boiler without consulting the manual. Over-pressurising can lead to leaks or damage.

2. Know the signs of low boiler pressure

“Low boiler pressure doesn’t just stop your heating from working,” Ryan warns. “It can also indicate leaks or other underlying problems in your system.”

Common symptoms include:

1. No hot water
2. Radiators that stay cold
3. A pressure gauge reading below 1
4. Error codes on your boiler

Worst way to deal with it: Ignoring it. Low pressure won’t fix itself, and a neglected boiler could end up costing you more in repairs.

“Letting the problem go unchecked often results in bigger issues, from leaks to a complete system failure, making a small fix turn into an expensive repair,” says Gill.

3. How to repressurise your boiler safely

Repressurising your boiler might sound complicated, but it’s straightforward if you follow the right instructions. Check your user manual for specific guidance on repressurising your boiler, but generally it follows these simple steps:Turn off the boiler and let it coolLocate the filling loop, filling key, or filling link - typically found underneath the boilerOpen the valves slowly, watching the pressure gauge riseClose the valves once the pressure reaches 1-1.5 bars

“If you’re unsure or the pressure keeps dropping, call a Gas Safe registered engineer,” Ryan advises.

Common mistake to avoid: Forgetting to close the valves after repressurising - this can cause overpressure, which can be dangerous.

4. What to do if the pressure is too high

As your boiler heats the water for your radiators and taps, the water expands. This is why you'll see a difference in your boiler pressure when the heating is on versus when it's off.

"While high pressure is less common than low pressure, it can be more dangerous," says Ryan. "Low pressure is usually the result of leaks or air in the system and is easier to fix by repressurising or bleeding the radiators. But high pressure can put extreme strain on your heating system, potentially causing leaks and valve damage."

To reduce pressure:

• Bleed your radiators to release excess water. You’ll find a simple to follow guide on our website (
• If your boiler has a filling loop, make sure the valves connected to it are fully tightened. The filling loop is the flexible pipe that connects your boiler to the water supply. If the valves are left open, they can let water into the system, causing the pressure to rise.
• If the issue persists, it may indicate a faulty part, like the expansion vessel.

Avoid this dangerous mistake: Never open the boiler’s safety valve yourself. A boiler’s safety valve - also known as a pressure relief valve (PRV) - is a critical safety feature that prevents dangerously high pressure from building up.

If your boiler pressure is too high, do not attempt to fix it by opening the safety valve yourself. Only a qualified heating engineer should handle safety valve issues to ensure your boiler remains safe and functional.

Manually tampering with it can cause serious damage, make the problem worse, and even create a safety hazard. Always call a professional, rather than attempt to locate it yourself.Why boiler pressure matters

"Boiler pressure affects the efficiency and safety of your heating system," Ryan stresses. "Getting it wrong can lead to higher energy bills, frequent breakdowns, or even a complete boiler replacement."

“Whether you're dealing with low pressure, high pressure, or the dreaded "boiler not working" error, the key is to act quickly and avoid DIY disasters.

“At BOXT, we pride ourselves on full transparency when it comes to pricing. If we can fix your issue during a one-hour inspection without needing parts, the cost will be a straightforward £89. For more complicated issues that require specific parts, we’ll give you a clear, no-obligation fixed price upfront, so there are no surprises. You can also find our fixed-price repair costs directly on our website, giving you peace of mind from the start.”