The pressure in your boiler is crucial to its proper operation. When it loses pressure, this can lead to heating or hot water failures, as well as damage to internal components. It’s important to understand the reasons for this loss of pressure, so you can react quickly and avoid costly repairs. Discover the main causes and solutions below.
Causes of pressure loss in a boiler
There are many reasons why your boiler may be suffering from low pressure. Understanding these causes will help you better maintain your system and avoid frequent breakdowns.
Leaks in the heating system
Leaks are one of the most common causes of pressure loss. They can occur in pipes, radiators, fittings or even boiler seals. Even small water leaks can cause a gradual drop in pressure. If you notice moisture or rust around your pipes, it’s likely that a leak is the cause of the pressure drop.
Expansion vessel problems
The expansion vessel is an essential element in compensating for variations in water volume caused by heat. If the expansion vessel is defective, incorrectly adjusted or at the end of its service life, it may no longer play its role correctly, resulting in a loss of pressure. A defective expansion vessel can also cause over- or under-pressure, impairing the operation of your boiler.
Air trapped in the heating circuit
When air is trapped in the heating circuit, it prevents water from flowing smoothly through pipes and radiators. It can also affect pressure. This phenomenon often occurs when radiators are not properly vented. The presence of air in the system can also reduce heating efficiency, resulting in excessive demand on the boiler.
Filling valve failure
The filling valve is a mechanism that maintains boiler pressure by adding water when necessary. If this valve is incorrectly closed or defective, water can slowly escape, resulting in a loss of pressure. A faulty valve can also prevent the boiler from filling properly, contributing to insufficient pressure.
Heating circuit purging problems
Incorrect or faulty venting can also be the cause of pressure loss. If the system is not properly vented, air can accumulate in radiators and pipes, preventing proper water circulation and, consequently, reducing boiler pressure.
What to do if you lose pressure
If your boiler pressure drops, it’s important to take a few steps before calling in a professional. Here are the steps you can take to solve the problem.
Check pressure regularly
Keep your boiler pressure between 1 and 2 bars. Use the pressure gauge on the side of your boiler to check the pressure regularly. If it falls below 1 bar, you’ll need to add water via the filling valve.
Bleed your radiators
If air has accumulated in your radiators, you need to bleed them. To do this, switch off the boiler, then use a bleed wrench to release the air. Once the air has been evacuated, check the pressure and adjust it if necessary.
Inspect pipes and radiators
Examine pipes and radiators for leaks and moisture. If you find any leaks, it’s important to call in a professional to carry out the repairs. Don’t try to repair leaks yourself, as this could make the problem worse.
When should you call in a professional?
If your boiler pressure continues to drop despite your attempts to correct it, it’s time to call in a qualified heating engineer. A persistent loss of pressure may be a sign of a more serious problem, such as a leak that’s hard to locate, a faulty expansion tank or a major fault in the system.
Why choose Leader Services for your boiler?
Leader Services provides qualified heating engineers to solve all your pressure problems and maintain your boiler. Our experts are trained to identify the underlying causes of pressure loss and to remedy them quickly. Our comprehensive boiler maintenance service guarantees your boiler’s smooth operation and long service life.
Discover our services
If you’re having pressure problems, or simply want preventive maintenance, visit our boiler page on Leader Services – Chaudière.
Contact us
Don’t let a loss of pressure cause damage to your boiler. Contact us now via our contact form for a full diagnosis and rapid intervention. Our experts are here to help you keep your boiler in top condition.
