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What To Do If Your Boiler Pressure Is Low

As winter is fast approaching, it's time for us to ditch the fans and shades and prepare for cold evenings in front of the TV. There's no denying that there's something special about the colder season, but households become more reliant on having a steady supply of central heating and hot water available.

One of the worst things that can happen during winter is losing your hot water supply. Not only is it incredibly inconvenient, but it can also impact your family's hygiene. Let's face it, nobody wants to bathe in cold water, and while there's the tried and tested method of boiling the kettle, it takes ages, and most people decide it's not worth the hassle.

In most cases, you'll lose your hot water if the boiler pressure is low. But how can you fix it? In this short guide, we'll reveal everything you need to know, so you can fix low boiler pressure without calling in an engineer.

Why Is Boiler Pressure Important?

Whether you have a combi boiler or a conventional boiler, it's a complex system that requires your pipes and water system to work flawlessly. Every boiler heats cold water and circulates it around your property.

Your pipes, radiators and hot water tank (if you have an older boiler) can only function if the boiler can heat water. The biggest issue with this is maintaining the correct pressure levels.

If a boiler's pressure is too low, it won't adequately heat cold water, which means households will be without both water and central heating.

Why Does Low Boiler Pressure Happen?

The two most common causes of low boiler pressure are bleeding radiators and leaks. When you bleed a radiator, you release trapped air from the cavity, which often results in lower water pressure if too many escapes.

Even the tiniest of leaks can also cause problems with your boiler pressure, so it's always a good idea to check around the boiler exterior to see if there are any wet patches.

There could be a leak inside your boiler system, but you should wait for a gas safe registered engineer to fix the problem - especially if there might be water damage to the control panel.

Checking Your Boiler Pressure Gauge

In most cases, you'll be able to view your boiler pressure gauge on the front of the boiler system. The dial will show numbers, with green and red zones to symbolise the pressure level. If you have a digital pressure gauge, it will display the reading in numerical format.

The critical thing to remember is that your boiler pressure should be between 1-1.5 bar. Low and high pressure can damage your system and connected appliances, so it's essential to do what you can to correct the pressure.

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Low Reading: Use The Filling Loop

Anything below a reading of 1 bar means your boiler won't be able to provide adequate power for your central heating system to work. Luckily, if the pressure is too low, it's pretty easy to fix - but you should always refer to your manual before trying to fix the low pressure.

The boiler filling loop is a temporary connection hose that joins your boiler system to the mains water supply. If you bleed your radiators, water will likely escape, but your manual will provide clear instructions about using the filling loop to repressurise the system.

Is low boiler pressure dangerous?

If your low boiler pressure isn't down to leaks from the radiator system, you should check around your system for any damp patches. A leak can cause the pressure to drop, and while some people try to fix the issue themselves, we recommend calling a gas safe register engineer.

There could be leaks inside the boiler, which might damage the internal components. If that's the case, you could cause more damage by trying to fix the leak yourself, so we recommend that if you can't locate a leak outside of the system, you call the professionals in.

High Boiler Pressure

When it comes to issues with your boiler pressure reading, it's usually low water pressure that occurs - but if you notice a high-pressure reading, it could be a potentially dangerous situation. Your pressure gauge should be 1.5 bar, but if it gets to 2.75 bar, then you should take steps to fix the issue immediately.

It's best always to call in an engineer because if you have to bleed the radiators, you could be dealing with hot water, which might cause injuries.

Repressurising a Boiler: The Simple Step by Step Guide

If your boiler is losing pressure, you should always check the boiler manual for advice on how to fix your specific model. It's relatively simple to repressurise your boiler, and this simple step by step guide should make the process a lot simpler.

We recommend referring to the manual before following this process, as conventional and combi boilers might require a different approach.

  1. Switch your boiler off and make sure it cools down. The last thing you want is to be dealing with hot water!
  2. Attach your filling loop and make sure it's secure.
  3. Gently open the valves to let water into the system. You should be able to hear water flowing between the mains supply and your boiler.
  4. Leave the water running until the pressure gauge reaches 1.5 bar.
  5. Turn off both of the valves, and turn your boiler on. Some systems might need to be reset, but your manual will tell you if it needs it.
  6. You can now remove the filling loop, but make sure there's no water leak.

Should I Call a Heating Engineer?

While most people can follow simple instructions to correct their system when it shows a boiler pressure too low reading, too much pressure often requires a gas safe engineer to correct the problem safely.

At Hometree, we offer a range of fixed price boiler servicing plans for both households and landlords. Your boiler is an essential appliance, and when the pressure drops or increases, it can cause a range of problems.

Our annual servicing plans ensure you get a free yearly boiler check and service and access to 24/7 emergency callouts from a qualified heating engineer.

With a range of cost-effective practices, you'll never have to worry about your gas appliances again. Whether responding to a pressure warning or repairing a broken boiler, our heating engineers will ensure you get the best service.

If we need to replace your old boiler with a new boiler, we'll make sure it's the last resort and discuss the alternative repair options with you.

Contact us today, and our friendly customer service team will be happy to discuss our packages. If you want to be free of colder rooms, fluctuating boiler pressure gauges, and hefty heating bills, our cost-effective packages are the good news you've been waiting for.

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