When Your Boiler Timer’s Not Working, Do This To Fix It

By far, one of the most common boiler issues we encounter is the boiler timer not working. At first it may seem like some other component of the heating system is malfunctioning.

After a few years, these clocks are prone to developing flaws. They either stop working completely or act up randomly, such as turning themselves on or off.

On the other hand. It’s critical to appropriately identify a faulty boiler timer. We’ve responded to situations when a new clock was installed by another installer, but it wasn’t the issue.

Boiler Timer Normal Operation

Before we discuss the potential causes, it is essential to find how your boiler timer works. It will help you identify and fix the central heating system more efficiently and quickly. Typically, when you turn on the hot water tap, the boiling water should instantly start flowing.

A decent boiler timer will provide flexibility to satisfy these demands because some homes consume more hot water on certain days than others. Assume that one member in a home showers in the morning while the other showers at night. Setting your boiler settings to ensure that the hot water is on and ready to go at these exact times will ensure that the hot water does not run out, saving you time, irritation, and energy.

Timers, on the other hand, are cost-effective when it comes to controlling the heating. Do you have to go to work throughout the day? Setting your boiler’s timer to prevent the heating from turning on is a smart way to save money. The main drawback to using a timer is that most timers – which consist of a round dial with a 24-hour clock in the middle – don’t have the ability to adjust to different schedules, such as ensuring that the heating is turned on on weekends.


The Common Boiler Timer Faults

There are myriad reasons why the boiler’s timer controls are not working. The good news is that most of these problems are easily fixable. In this section, we’ll briefly highlight the common reason why that boiler timer has been misbehaving.

Thermostat Fault

Timers are designed with a little more durable material than thermostats. The main reason for this is that they are integrated into the boiler and are extremely difficult to replace.

The temperature of the room will be monitored by your room thermostat. It should activate the boiler when the temperature falls below the desired value. If the thermostat is broken, it may not be able to communicate with the boiler or inform it to turn on.

Another possible issue is the thermostat’s position in the home. If the thermostat is placed too close to a heat source (radiator), it will believe the room is hotter than it actually is and switch off.  Similarly,  If the room thermostat is too close to a draft, it will believe the room is much colder than it actually is and turn on the heat.

If you’ve discovered that your house is much colder or hotter than it should be, and you’ve moved the thermostat to a new area, it’s possible that the new location is the source of the problems.

Daylight Savings

Believe it or not, we all make this type of mistake at some stage or other. In the UK, we can all get thrown off by when the clocks switch forward or back. Save yourself some hassle and check the time on your boiler and the time on the radio match before making any calls for repair.

Power Issues

Often an interruption to the power supply can cause the boiler timer to reset, especially on some older models. Be sure to check the time is accurate. If there is no problem, it could be a simple as checking the fuses.


Fixing A Broken Boiler Timer

Finally, an essential part that has got you glued to this piece. It’s time to fix that broken boiler timer so that your central heating system is up and running again. We’ve divided this section into several parts based on the different issues. Let’s get reading!

Central Heating Time Settings

Many boilers still use an old mechanical clock. If this is the case with your boiler, you should understand when the radiators turn on and off by themselves. A power outage is another common reason why your boiler is not working.

Sometimes, the power can go off whenever you are not at home. You can determine this situation by looking at the other clocks in your house. Power cut can cause the boiler timers to reset. Because of interruptions in the boiler’s electrical supply, it might not fire up when needed.

The seasonal clock change can also cause your combi boiler not to work. Additionally, the situation also might be due to damage to mechanical controls.


The only solution here is to keep an eye on the timer settings. The timer clock of your boiler is prone to confusion owing to various reasons.

Recent electric work, electricity supply cuts, and seasonal changes can be the reason behind the faulty timer. Any of the mentioned reasons can result in your boiler completely shutting off.

You must check if the central heating time settings are correctly set or not. Often, the day and nights get mixed, and your boiler timer will be working in the opposite direction. In case you are having issues with the timer controls, the best thing to do is hit the reset button.


The above solution didn’t work? Maybe it’s time to check the power supply. You can start your fixing process by checking if the boiler is receiving power or not. Is the boiler turned on? Is the boiler heating? Besides, some models possess different switches for radiators and hot water.


If your boiler model has different switches, then you must move to the fused spur. On the frontal plate, you can find the blown-up electrical fuse. Usually, this fuse is not hard to locate, as it already comes with a sign. To fix this issue, remove the cover and replace the fuse with a new and correct size one.

The dodgy wiring can also prevent your boiler from properly functioning. It is better to get a gas safe engineer or call a professional to check out this issue.

Note: Always make sure to check if the electric supply is off before reaching the fuse.


Thermostat Problems

The sensors inside the thermostat device allow it to analyze the temperature of the area. The air around this tiny device triggers the heating in the boiler to shut on and off. If the room temperature is cold, it will automatically turn itself on, and vice versa.

Another reason behind the thermostat malfunctioning is dying batteries. There can also be a fault with your thermostat due to the build-up of dirt and debris.


The solution to the fault in the thermostat is to replace the dead batteries. Remember to wear gloves while removing the batteries. You may also be required to clean the thermostat. Check the dirt sites in the thermostats, and remove them effectively with cotton buds or a soft brush.

You must also take a look at the location of the thermostat. The thermostat might not be working because there are heating sources near it. Make sure that the thermostat is away from kitchen appliances and direct sunlight.

Heating & Hot Water Settings

This issue here is pretty obvious, yet one of the significant reasons your boiler timer is not working. Make sure that you have shut off the heating instead of turning off the hot water.

Even if you haven’t, someone else in the house might have done it by mistake. In this case, you don’t need to do anything but only switch the hot water back.


If you have a new boiler, you might notice that it has a mechanical timer. The old but gold way to fix boiler clock problems is by resetting the controls. Remember that these boilers may revert to 12-midnight. You have to use the manual to set and change the time correctly. The boil timers can get a too complicated affair if you ditch the user manual.

Brand Specific Boiler Timer

Boiler controls may indeed differ from one brand to another. Especially if you’ve bought a new boiler home, it may give you a tough time to turn itself on. If you have a new boiler from a different brand, it is better to resort to the user manual.

The user manual is the right place to understand the problem in your boiler or boiler timers. Though the suggestions mentioned earlier are common boiler fixes, you can also take an engineer’s help. For further information about a brand-specific boiler clock, you can refer to the table below.

What to Do If Your Boiler Timer Still Isn’t Working

If none of the above solutions are working, it is better to call up a gas safe engineer to check and fix the problem with the programmer. It is better to call a professional to come and visit your broken boiler. These professionals will have time-tested solutions to make your boiler start working and heating again.

You may need to call for professional help if you see a completely broken thermostat that can’t detect the temperature. The gas safe professionals thoroughly check the boiler heating system. They will correctly identify the core of the problem in the radiator or the boiler.

No matter what brand, the plumbers will set your boiler heating mechanism in no time! If your professional cannot repair the boiler still, maybe it is time to get a new one.

Last Updated on November 7, 2021

Frequently Asked Questions

Why is the boiler timer not working?

Your boiler timer may not be heating due to several reasons. If it’s a new boiler that is not working, it also may be due to faulty manufacturing. However, it can also be because of a broken thermostat that your boiler is throwing problems. Often, an electric outage can also be an underlying reason behind the problem in your boiler.

How do I reset my heating timer?

If your boiler is not heating and is still cold, you may need to reset the timers. To reset the boiler, turn off the unit, and turn it on again after 60 seconds. Doing this will also reset the boilers clocks.

What do you do if your thermostat is not working?

If your thermostat is having a problem, you may need to replace it immediately. However, you can try out a few things like cleaning the thermostat or replacing the batteries. Also, try to place the thermostat in a different location and see if it has any effect.

David Thompson

Author: David Thompson

Dave has been involved in the UK building sector for over 3 decades and has developed a particular interest in energy efficiency in the home.

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