Updated on 23rd August, 2023 by Martin Astley
Why Is My Boiler Losing Pressure?
Is your boiler losing pressure? If yes, it indicates that the water is not reaching the necessary force to heat your home. You can face this issue due to various circumstances. For example, if you live in an area where temperatures drop below freezing frequently. Or if you are relying on your home’s heating system for an extended period when you are not there to turn it on and off as needed.
Many factors could lead to the boiler slowly losing pressure, including lack of boiler maintenance and annual boiler service. However, that doesn’t mean it’s always impossible to solve the problem. And get your boiler back up and running again.
This article will discuss in detail why your boiler keeps losing pressure. And how you can fix it.
What is Boiler Pressure?
Pressure is the amount of force at which water is being pushed out of the boiler. It is measured in pounds per square inch or PSI. The pressure inside a boiler will determine how fast the water will boil. It is very crucial to maintain your boiler pressure. And track whether it is too high or too low.
If you have a combinational boiler, a ‘filling loop’ that links to your water line will keep the pressure up. Your water pressure must be stable as the pipes expand and contract with the heat for your boiler to perform safely and efficiently. It ensures that no difficulties develop when your home is being heated.
What Pressure Should My Boiler Be?
When it comes to the boiler pressure. 16 PSI is the ideal amount. However, lower pressure is not always a cause for concern. It will depend on the specific situation, like what type of boiler you have. If you have an older boiler, you may experience lower pressure more often than a newer system. If your boiler has been used for several years, it may be worn out and need replacement.
In addition, If you’ve had one-off boiler repair in the past, you may need to replace it sooner rather than later. If your house has a newer boiler, you may occasionally have a lower pressure reading, but it shouldn’t be a consistent problem.
How Do I Check the Boiler Pressure?
- You’ll need to locate the pressure gauge on your boiler to check the pressure.
- The position of the needle will be between 1 and 2 bars if the pressure is correct.
- Most boilers detect when the pressure is incorrect and shut down if the pressure drops too low.
- If the pressure in your boiler drops below one, the boiler will shut down, leaving you without hot water.
- Furthermore, if your boiler pressure is too high (needle above 2), it may cause your system to fail.
Boiler pressure should be between 1 and 2 bars. But it’s recommended to double-check with your manual. Green is commonly observed in the gauge area between 1 and 2. When pressure exceeds 2, the load on your system, including pipework, radiators, and components, increases—potentially causing problems.
What Should The Pressure Be on a Combi Boiler?
The pressure of your combi boiler may vary between 1 and 1.5 bar if your pressure reading is less than 1 bar. It may be possible that you have lost the water from the system through a leak. If the pressure is 2.75 bar or above, you may need to bleed a radiator to relieve the pressure and return it to a safe level.
If you try to bleed a radiator, make sure you have a mechanism to catch the water so the walls and floor don’t get destroyed. Take care when doing this task because the water can be boiling hot. It’s a good idea to call an engineer for assistance if you’re unsure about anything.
In case you discover a leak or suspect that you have one. You should contact a plumber who can inspect and resolve the issue.
How Often Should I Check My Boiler Pressure?
- Just after summer, check your boiler pressure before turning on you’re heating for the winter. So that you can avoid complications when the weather turns colder and you want to turn on your heating.
- After you’ve bled your radiators, you’re ready to go. You should check your boiler pressure after bleeding your radiators because this can cause the pressure in your boiler to drop.
- Check your boiler pressure if you have cold radiators or cold water, as this could be the source of the problem.
- If your boiler makes a strange noise, it could be the consequence of a pressure issue, so check your gauge.
What Causes a Boiler to Lose Pressure?
Here are some of the most common causes of low boiler pressure:
1. Water leaks
A leak from your pipes, boiler, or radiators can be challenging to detect. But look for wet areas and water around your home. However, it would be best if you never tried to find leaks in the boiler. Instead, contact a Gas Safe licensed professional.
2.Bleeding of Radiators
When you bleed a radiator, you’re releasing air, which lowers the pressure in your system and can result in a drop in water pressure.
3. A Clogged Filter
Suppose debris is clogging your filter. Especially if you have hard water, this may be affecting the pressure inside your boiler. It can sometimes lead to the need for a new filter and cleaning of the water feeder.
4. Low Water Temperature
Suppose the water temperature inside the boiler is too low. It can be difficult or even impossible to reach the necessary pressure to heat your home.
5. Malfunctioning Gas Valve
The gas valve not working correctly could indicate that something is blocking the gas line or that the valve needs to be replaced.
6. Low Gas Pressure
Suppose the gas pressure is too low. It can prevent the water from reaching the necessary force and result in reduced flow.
7. Low Water Supply
If your water supply is too low, it can cause low pressure.
8. An Oversized System
Particularly a boiler, which requires more pressure to work effectively.
9. A Build–up of Corrosion in the Water Feeder
Corrosion can reduce pressure. And prevent the water from being appropriately distributed through the system.
How to Fix it?
To fix low boiler pressure. You will likely need to find the root of the problem to know how to fix it. There are many potential causes of low pressure, and you’ll want to rule out the most common ones before moving forward with any repairs or replacements.
- Clean or replace your clogged filter. A clogged filter could be causing the low pressure in your boiler.
- If your water is too cool, it may not be able to reach the necessary pressure to heat your home. Consider adjusting the settings on your thermostat. Or even turn up the water heater if required.
- Check the gas line to make sure that nothing is blocking it and that it is functioning correctly. If not, you may need to have it replaced.
- Suppose the gas pressure is consistently low. Then this can be a sign that there is a problem with the line, so you should have it checked out by a professional.
- If your water supply is too low, this can lead to intense pressure and cause issues with your boiler.
- Sometimes the reason for low boiler pressure can be your boiler being oversized, requiring a lot of pressure to work efficiently. Consider replacing your boiler with a system that works at a lower pressure.
- Clean up the build-up of corrosion to improve the pressure in your system.
Is Low Boiler Pressure Dangerous
Low boiler pressure is rarely a cause for concern. But if you have any doubts, you should always seek the counsel of a licensed Gas Safe Engineer. Low boiler pressure indicates that water cannot be circulated throughout your system or provided to your faucets and showers. As a result, the boiler will typically shut down and display an error code to notify you that a problem is causing low pressure.
Any boiler, even the most ‘popular’ brands, can experience pressure loss. The most prevalent ones are listed below (with error codes).
List of Boiler Error codes for losing boiler pressure
Error codes are used in some electronic boiler models to alert you to severe issues, such as a leak or a sudden increase in the amount of air in the system.
These codes can assist you in identifying problems before they become more serious, and they may even help you repair the system before it enters a lockdown or shutdown mode. Remember that not all codes apply to all boiler types; others may only display in specific situations. Always check your handbook for this information to avoid making a mistake and attempting to tackle the wrong problem.
- Fault Code C1 = Differential air pressure.
- Fault Codes B9, ED, F0, F-ED, F-EE, F-E5, F-EC, F-EF, F-FD, F-FF = Maximum pressure limiter fault.
- Fault Code F5 = Faulty gas pressure.
- Fault Codes EE and EF = Faulty air pressure.
- Fault Code 0F = Service required.
- Fault Code E9 = Safety limiter.
- Fault Code A1 = Dry pump.
- Fault Code F0 = Major internal error.
- Fault Code CE 207 = Low water pressure present.
- Fault Code H07 = Low water pressure that is impacting performance.
- Fault Code 1065 B = Pressure sensor is defective.
- Fault Code 1970 B = Sudden, rapid pressure drop.
Fault Code F1 = low water pressure.
Should I Try to Fix the Boiler on My Own?
If your boiler has pressure problems, you may need to hire an expert or a specialist to come out and fix it. There are dozens of reasons a boiler loses pressure, and not all of them are evident without disassembling the boiler unit. Of course, taking it apart exposes you to the danger of losing pieces or harming something.
You can generally fix things like a tiny leaking pipe yourself, but an engineer might be able to figure out why that line was broken. External causes of leaks, such as corrosion-causing leaks or a bending pipe more prone to wear down faster, can sometimes go undetected.
Extreme damage should be left to a qualified professional, and you should never attempt to repair something you don’t understand.
Still, Having Trouble?
If your boiler is still making trouble, then you should not further tackle around your boiler pressure and immediately book a safe gas engineer to have a look and repair your system to avoid any unforeseen consequences.
If you are a 24/7 Home Rescue customer, you can reach us anytime on 0345 0774 177 to get immediate help over the call or book a professional repair appointment.
Our technical team will run through some simple troubleshooting to see if they can resolve your problem on the phone, or they can book one of their friendly and knowledgeable Gas Safe registered engineers. To get you back up and running as soon as possible.
You can always avail of our one-off repair service at a fixed rate if you are not a 24/7 Home Rescue customer.
Can a boiler lose pressure without a leak?
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