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The boiler is an integral part of our homes. Many people have heard “low pressure,” but what does it mean? Low pressure could be to blame if your boiler is giving you trouble, like not heating or boiling the water. Read our guide to learn how to increase boiler pressure.
Our helpful guide can help you determine why the pressure in your boiler is lower than usual. Simple checks and ways to increase boiler pressure can also help.
Understanding Boiler Pressure
Boiler pressure is the hot water pressure in your sealed central heating system. It’s measured in bars, and most boilers operate efficiently between 1 and 2 bars of pressure. You’ll typically find a pressure gauge on your boiler’s front, indicating the current pressure.
What is Low Boiler Pressure?
The boiler heats cold water that flows around the pipes and radiators in our homes. The boiler system pressure must remain stable to work as efficiently and consistently as possible. If the pressure in your boiler goes below what it should be, it won’t be able to heat the cold water enough so that you won’t have any heat or hot water. As you might expect, each type of boiler has different exact pressure needs. Check the manufacturer’s handbook or manual to quickly and easily determine your boiler pressure. Your boiler’s correct pressure information and accurate measurement details are here.
What Causes Low Pressure on a Boiler?
Because so many things are going on inside your boiler, it’s not surprising that the pressure can change. Why does the pressure in your boiler drop? This is important to know. One of these common problems could be the pressure gauge number needing to be higher.
Water Leak
It’s normal for pipes to leak; even a tiny crack can lead to a leak that causes significant problems for your boiler. It is best to have a professional check for leaks inside your boiler system. However, looking for leaks around pipes and radiators, including where the pipes join and bend, is accessible. Look for wet spots on the floors and the outside of the boiler.
A leak inside the boiler could cause a slow drop in pressure, but you shouldn’t try to find leaks inside the boiler yourself if your boiler’s control panel has water damage; only a qualified expert knows how to fix it.
You shouldn’t try to fix a broken boiler part by yourself. If you don’t know what to do, call a boiler expert. They can help you figure out what’s wrong.
Radiator Bleed
If you bled one or more of your radiators not long ago, the pressure in the system may drop. You get rid of air stuck in the system by bleeding a radiator. The pressure must rise again for the water to replace the air.
How Can I Check My Boiler Pressure?
You can quickly and easily check these things to see if your boiler pressure is correct or too low.
On the front of the boiler, you’ll find the scale. Most regular boilers have a digital screen with number bars (a green-to-red warning screen) or a round hydraulic gauge with a needle on a wheel showing the pressure level. Most of the time, the pressure gauge for an older boiler is under the boiler. The pressure is usually between 1 and 1.5. Air can drop below this level if there is a leak or after a radiator bleed. When the boiler is turned off, it should be around 1.
It’s not enough pressure if:
- The reading is less than one (one bar), or the needle has dropped below 1.
- The LCD shows a flashing warning message or number.
If you need help with what to do, look at the guidebook that came with your boiler.
How to Fix Low Pressure?
The good news is that you can fix the pressure yourself with a few easy steps. If the pressure is less than 1.5, the boiler must be re-pressurised. This simple task will keep your boiler running well. If you have checked the lines and the area around the boiler for leaks, you can fill the system with more water. If this doesn’t work, do these things.
- In the boiler instructions, look for the parts that indicate low pressure.
- Turn off your boiler and wait an hour for it to cool down.
- Ensure that both ends of the filling loop are connected (your boiler might use a key instead).
- You can hear water coming in when you open both taps.
- Make sure the pressure gauge is at 1.5.
- One at a time, close both valves all the way.
- You might have to press the reset button to turn the boiler back on.
- Take off both ends of the filling loop and use a towel to catch any extra or dripping water.
- Keep the key or filling loop somewhere safe.
You can use a filling loop or key to re-pressurise your boiler.
Still Need to Increase Boiler Pressure
If you can’t find the filling loop or key or are still having trouble controlling your boiler’s pressure, you should have a professional re-pressurise it. Call an expert if you need help determining what’s wrong and how to increase boiler pressure.
Do You Have a Faulty Boiler?
If you see a 1-bar jump or the pressure needle goes into the red area above 2 bars, the pressure release valve or expansion vessel may break. For these kinds of problems, you will need a licensed and trained service worker.
The cost to fix these problems can change depending on the extent of the damage. Most engineers charge by the hour, but you should always check their qualifications and ensure the Financial Conduct Authority regulates them.
Are You Eligible for the ECO4 Free Boiler Grant?
The ECO4 Grant is designed to help households improve energy efficiency. If your property’s EPC rating is E, F, or G, and you have a non-condensing boiler, you could qualify for a free boiler replacement.
Find out if you’re eligible for the government boiler scheme today.
Conclusion
Keeping the boiler pressure at the right level is essential for running your heating system smoothly. By implementing these steps in this guide, you can safely and effectively increase boiler pressure, ensuring your home stays warm and your hot water supply remains consistent. Regular maintenance and checks will help you avoid potential issues, but always remember to seek professional help if you need clarification or encounter persistent problems. With the proper care, your boiler will continue to operate efficiently, providing reliable heating and hot water for years. Hope this guide has cleared you how to increase boiler pressure.
Frequently Asked Questions
Why Is Boiler Water Pressure Important?
It is essential to have good boiler water pressure because your boiler warms cold water that runs through your home through pipes and radiators. For a combination boiler, the pressure will be kept up by a loop that links to your water pipe and fills with water. Your water flow needs to stay stable when the pipes expand and shrink with the heat so your boiler can work as safely and efficiently as possible. This will also make sure that there are no problems when your home is heated.
What is A Normal Pressure Level For A Boiler?
A central heating system gauge with a pressure level between 0.7 and 2.5 bars is suitable for boilers. This will ensure that water heaters and heated towel bars can connect to the network and heat the house properly.
What Causes Low Boiler Pressure?
Low boiler pressure is usually caused by leaks in the radiators, the boiler’s pipes, or other parts that don’t work right. If you don’t fix it, it can worsen and cause problems with your whole heating system.
How Often Should You Increase Boiler Pressure?
The system’s pressure usually requires topping up once or twice a year. If you frequently need to repressurise your heating system, please contact your installer.
Is Low Boiler Pressure Dangerous?
When boiler pressure is low, water can’t usually reach your faucets and showers or move around your system. Because of this, the boiler will usually turn off and show you an error code to let you know there is a problem with the low pressure.
When your boiler pressure is low, it’s usually nothing to worry about. But if you are worried, you should always talk to a trained Gas Safe Engineer.
