Your boiler is a specialist and expensive piece of equipment that is the beating heart of your central heating system. Because it is often hidden away in an airing cupboard, it is something that can easily be forgotten or neglected. Yet, neglecting your boiler can be a very costly error requiring a new boiler, which can easily be avoided with a little care and attention.

Modern gas boilers are a lot more complicated and require tools, technology, and expertise to service them, but there is one key factor that every homeowner should pay attention to – your boiler pressure. For a boiler to operate efficiently, it needs to function within a relatively small pressure window when it is running.

Our advice is to check the pressure in your gas boiler every two weeks or so, a process that should only take a matter of seconds.  If you notice that the pressure is too high or too low, you will quickly be aware that there is an impending problem and can take preventative action to ensure a more serious issue does not develop.

Learning how to reduce boiler pressure is not an particularly difficult, but could potentially safe you thousands of pounds in unnecessary boiler repair bills. Bear in mind that high boiler pressure will not only affect the hot water in your home, it will also have a direct impact on your central heating.

Expansion Vessel & Boiler Pressure Gauge

What Happens If Boiler Pressure is Too High and Why It Is Essential That You Reduce It As Soon As Possible 

The first thing you need to understand is what boiler water pressure actually is. In layman’s terms, it is the balance of water and air within your central heating system. If your system’s pressure is too high, it could cause water to escape out of the pressure relief valve. The solution to this problem is to lower pressure in the system, so let’s have a look at how you can do that.

What Causes High Boiler Pressure

There are a number of different reasons why your boiler pressure might be high. Before we go into those reasons in greater depth, it is important that you do not become obsessed with checking your boiler pressure every five minutes, because in certain situations your boiler pressure will rise naturally such as when the heating is on or someone is running a bath for instance.

Once the heating turns off, or the hot water tap is no longer flowing the pressure will return to its previous level. In an efficient boiler the pressure even with the heating or hot water on should never rise above 2.5 bar, and the confirmation that there is a problem with high boiler pressure, is when your boilers pressure gauge does not return to normal afterwards.

The main reason for high pressure as discussed below is too much water in the system, with the second issue being defective parts. Before we go into how to resolve this problem, lets discuss what the ultimate boiler pressure should be.

What Is The Optimum Boiler Pressure?

Although there is no definitive answer to this question, as ever boiler manufacturer settings for boiler pressure will vary. However, in the vast majority of cases the normal range should be somewhere between 1 and 2 bars. Every modern boiler will have a pressure gauge normally located on the front panel of your boiler.

To make things even easier the gauge is normally colour coded, with green denoting the ideal pressure range and red donating some type of problem be that low boiler pressure, or high boiler pressure.

How To Lower High Pressure In A Boiler To Save Money And Reduce Your Heating Bill

Option A – Too Much Water In The System

The number one cause of high pressure in your boiler is too much water in the system. The 50 million dollar question is how to reduce that pressure. Sometimes, this can be self-inflicted when a homeowner has been dealing with low pressure in their gas boiler and has tried to repressurise it.

When checking your boiler’s pressure, it is vital to ensure that the boiler is switched off. When your boiler is on and driving the central heating system, the system’s pressure naturally increases and will give you an incorrect reading. If the pressure gauge shows anything above 1.5 bar, then your boiler pressure is too high, and you need to release pressure in the system.

Do not worry; this is a quick and easy fix and doesn’t require much technical knowledge. Your first step is to bleed the radiators. Purchase a radiator key from any good DIY store, and slowly turn the valve on the top corner of your radiators anticlockwise.This process will quickly help to remove and therefore reduce the pressure in your system.

Initially, you should hear a hissing sound, which is the air escaping, which in turn is reducing the pressure in the system.; eventually, the air should stop and be replaced by water. Let a millilitre or so of water out, and then tighten the valve again.

After doing this on each radiator, you should check the boiler pressure gauge to see if it is still showing high pressure. Your aim is to ensure that the needle returns to the gauge’s green section on your boiler. Once you have achieved this target, then your pressure is within the correct parameters, and you have nothing to worry about. Your heating and hot water should now be operating properly.

Option B – Defective Boiler Parts 

Although this will require the services of a professional, it is still something that you may be able to diagnose. There could be a problem with any number of different parts, including the pressure release valve, the diverter valve, or the filling loop, all of which you should be able to spot even without any knowledge or expertise.

The pressure release valve is a relatively simple piece of equipment that releases water when the boiler pressure gets too high. To locate it, search for a copper pipe, which generally can be found outside your home, on the wall behind your boiler.

This pipe should not be dripping water constantly, so if it is, it is a clear sign that there is some kind of issue, most probably that the boiler pressure is too high. If you see this, then, unfortunately, you need to call in a Gas Safe boiler engineer to deal with the issue.

The thing to remember is that most boilers have a lifespan of anywhere between 8 to 10 years, so unless you are particularly unlucky, any boiler under 6 is unlikely to develop an expensive fault. High pressure is more likely to be a sign that there is a minor problem rather than something serious to worry about.

However, it is worth remembering that undertaking any work on a boiler is best left to the professionals, so be careful. If in any doubt, contact a Gas Safe qualified boiler technician. The last thing you want in the middle of winter is a heating problem.

Prevention and Regular Boiler Maintenance Is The Key – A New Boiler Is Very Expensive

In addition to resolving intermittent problems, we strongly recommend an annual boiler service which could identify issues and problems before they become a more serious issue.

Some companies even offer boiler service plans which all you to spread the cost of the service over the year, and in addition give you priority should you experience a problem with your heating system.

Who You Need to Call for Your Boiler Problem Repairs If You Cannot Reduce Your Boilers High Pressure After Following These Tips

Here at ADI Leak Detection we are specialists at finding water leaks on central heating systems, a common problem when solve is when a boiler is losing all its pressure in a day from a hidden water leak!

Contact us today to discuss our range of services and how we can quickly and efficiently find any water leak in your heating system, regardless of size.

If your boiler pressure is too high then you need to source a local gas safe plumber by searching Google for a plumber near me.