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Heat your home efficiently

Your home’s boiler is responsible for providing heat to your radiators and hot water to taps. But what happens when your boiler pressure drops?

In this post, we’ll tell you how to safely adjust your boiler pressure to prevent unwanted error codes and unexpected high energy bills.

What is boiler pressure and why does it matter?

Your boiler needs a balanced level of water and gas at all times in order to properly heat your home and provide hot water. If your boiler pressure is too low, your boiler will stop working properly, while if your boiler pressure gets too high, it can be dangerous.

The pressure gauges on boilers are designed to keep track of the water pressure in the system and are often controlled automatically by a pressure relief valve (PRV).

Water is released via a small pipe if pressure gets too high and fed into the system by a filling loop if pressure gets too low. Sometimes you will need to take manual action to correct the pressure if you’re experiencing problems.

How do I know if my boiler pressure is too low?

The easiest way to understand your boiler pressure is to look at the hydraulic or digital pressure gauge on your boiler itself. Normal boiler pressure should be between 1 and 2 bars. Any figure above or below this range will require extra attention.

It’s important to note that water within your pipes will expand when your heating is on and cause your boiler pressure to rise as it warms and decrease as it cools.

Signs of low boiler pressure

If your boiler pressure is too low, you may be experiencing one of the following symptoms:

  • Fluctuations in water temperature: If you notice that your water isn’t as hot as it used to be or that the heat is inconsistently distributed, it could be due to low boiler pressure.
  • Strange noises from your boiler or heating system: Without the pressure needed to sufficiently heat and distribute water in your pipes, you may hear them bang, clank and rattle more than usual.
  • You have no heating or hot water: This is hard to miss. Exceptionally low pressure may cause your boiler to shutdown completely resulting in cold radiators and even colder showers!
  • Your radiators are only warm at the bottom: Air in your central heating system can prevent radiators from filling up and warming up properly. Bleed your radiators regularly to get ahead of such problems.

Remember that bleeding radiators can further reduce boiler pressure and make the situation worse before it gets better!

How to increase your boiler pressure

You can re-pressurise your boiler quickly and easily at home without the need of a professional plumber.

  1. First make sure that power to your boiler is turned off and that the system has cooled.
  2. Locate the boiler filling loop – the small flexible pipe that connects your central heating system to the mains water supply.
  3. Can’t find a filling loop? Your boiler may be fitted with a keyed or keyless internal filling loop instead. This simply means that the filling loop is located within the boiler with the valve made accessible in the casing – be sure to check the instruction manual for your specific make and model.
  4. Open both values of the filling loop (or your single keyed/keyless valve) to release water into the system until the pressure gauge reads 1.2 bar.
  5. Shut the valves and turn the power to your boiler back on.
  6. Turn on your central heating system to check everything now works as expected.

If your boiler proceeds to lose pressure quickly after re-pressurising, this could be the sign of a leak in your central heating system.

As with most home maintenance issues, checking for problems regularly and taking preventative action can save you a lot of money and stress in the long run.

At Miracle Leak Detection, we specialise in finding and fixing water leaks throughout Hertfordshire, Essex, Surrey and London.

Call us now on 0800 037 7078 to book a free visual inspection of your leak by one of our team.