How to Increase & Manage the Pressure in Your Combination Boiler

Have you ever suddenly found yourself with ineffective heating or no hot water? If you have, it’s likely the culprit was your boiler’s pressure. This is because, over time, the pressure in your combi boiler can drop — that’s why it’s important to increase and manage the pressure in your combination boiler from time to time. 

It’s all too easy to let the months roll by and not give your boiler a second thought. Shut away in the dark recesses of your garage or a rarely opened, cobwebby cupboard, we often forget this key home appliance works hard every single day. And like all things we rely on, it’s a good idea to check in on it now and again to make sure it’s happy. 

Keep an eye on the pressure gauge

Keep an eye on the pressure gauge

For your combination boiler to work efficiently, the pressure in the system needs to be between 1 and 1.5 bars on the pressure gauge. If the pressure drops below 1 bar, your pump and boiler will have to work harder, which will cause you problems. 

So, if you find your boiler has lost pressure and it needs increasing, follow the steps below to get it working effectively again. 

Step 1: Turn your boiler off and give it a few hours to cool down.

Turn your boiler off and give it a few hours to cool down.

Step 2: Find the filling loop. The filling loop is a flexible tube that is connected to your boiler by filling valves at either end. Make sure you can see the pressure gauge while increasing the pressure; this will reduce the risk of over pressurising your boiler. 

 Find the filling loop

Top Tip!

If you can’t keep an eye on the pressure gauge while dealing with the filling loop, ask someone to help you. 

Step 3: Using the tap handles or a screwdriver, open the filling valves. As you turn the valve counterclockwise, you should start to hear water.

Using the tap handles or a screwdriver,

Step 4: Watch the gauge as the needle moves up. When it reaches 1 bar, you can close the valves by turning them clockwise. 

Watch the gauge as the needle moves up

Step 5: When your gauge has settled at 1 or 1.5 bars, you can switch your boiler back on. 

1 or 1.5 bars

When you’ve increased the pressure in your combination boiler, it should be working well. But if you regularly have problems with ineffective heating, no hot water or your boiler constantly losing pressure, you may need to call out a boiler repair engineer to look at it. 

Don’t have time to deal with boiler issues or want any unexpected boiler repair costs? 

Then protect yourself with home and boiler cover from YourRepair. Our cover plans start from as little as £9 per month, giving you access to over 5000 gas safe engineers across the UK, a 24-hour call centre and the option to fix your cover price for 3 years — no matter how many claims you make. 

So, with 95% of repairs fixed on the first visit, let us look after your boiler. Call our friendly team today, on 0330 223 4422 for cover plan advice, an annual boiler service and safety check included and instant protection.