Why Does My Boiler Keep Turning Itself Off: Causes & How To Fix It

Last Updated on February 18, 2025

If you’re a homeowner or landlord in the UK, you know how frustrating it can be when your boiler keeps turning itself off. A boiler that’s constantly shutting down can leave your home cold, potentially raise your heating bills, and cause unnecessary stress. 

There are several common reasons why this may happen, and knowing what they are can help you fix the problem quickly—or at least understand whether you need to call in a professional.

In this blog post, we’ll take a look at the main reasons why your boiler might be turning itself off, how you can troubleshoot it, and when it’s time to get a professional involved.

Common Causes of a Boiler Turning Itself Off

1. Low Water Pressure

One of the most common reasons a boiler will turn itself off is low water pressure. Boilers require a certain level of water pressure to function properly, typically between 1 and 1.5 bars. If your system drops below this level, your boiler will often switch off as a safety measure.

• How to Fix It: Check the pressure gauge on your boiler. If it’s too low, you can usually re-pressurise the system by using the filling loop, which is typically found beneath your boiler. If you’re unsure how to do this, it’s always best to consult a professional heating engineer.

2. Blocked or Frozen Condensate Pipe

Another common culprit is a blocked or frozen condensate pipe. This pipe carries away the excess water produced during the heating process. During the colder months, the condensate pipe can freeze, causing your boiler to shut off.

• How to Fix It: You can try defrosting the pipe with warm water or a heat pad. Be sure not to use a direct heat source like a hairdryer, as this can cause damage. If the pipe is blocked, it may need to be unblocked by a professional.

3. Faulty Thermostat

A faulty thermostat can cause your boiler to shut down unexpectedly. If your thermostat isn’t working correctly, it may not be able to maintain the right temperature, leading the boiler to turn off.

• How to Fix It: Try resetting the thermostat or turning it off and on again. If the issue persists, the thermostat may need replacing, which is best done by a qualified engineer.

4. Air in the System

Air trapped in your boiler or central heating system can affect its performance, potentially causing the boiler to overheat or shut down.

• How to Fix It: Bleeding the radiators can help release the trapped air. If you’re unsure how to do this, a heating engineer can help.

5. Malfunctioning Circulation Pump

The circulation pump is responsible for circulating the hot water around the system. If it’s not working properly, your boiler may shut down to prevent damage.

• How to Fix It: If your circulation pump is faulty, it may need to be repaired or replaced. This is something that should be done by a professional engineer to ensure the system is working properly.

6. Overheating

Boilers are designed with safety features that shut the system down if it begins to overheat. This can happen if there’s a blockage in the system, such as debris in the pipes, or if there’s a fault in the pressure valve.

• How to Fix It: Check the pressure gauge and ensure there are no visible blockages around the boiler. If the problem continues, it’s best to call in a heating engineer to diagnose the issue.

When to Call a Professional

While there are some boiler issues that can be solved with DIY fixes, many problems require the expertise of a Gas Safe registered engineer. If you’ve tried the above troubleshooting tips and your boiler is still shutting down, it’s time to call in a professional. 

A certified engineer can carry out a full inspection, identify the root cause of the problem, and make any necessary repairs to get your boiler running smoothly again.

Is Your Boiler Old or Inefficient?

Sometimes, the issue isn’t a fault with the boiler itself but simply that it’s old and inefficient. If your boiler is over 10 years old, it may be time to think about upgrading to a newer, more energy-efficient model. Modern boilers are far more reliable and can save you money on your energy bills.

Request a free boiler quote today! Simply answer a few simple questions, and we will get back to you with a quote that suits your budget and needs. 

Whether you need a replacement boiler or just a repair, we can provide you with the best solutions for your home or rental property. Don’t wait for your boiler to break down completely—get in touch today for peace of mind.