How to Top Up Your Worcester Boiler with a Filling Hose
If your Worcester Bosch boiler’s pressure has dropped below 1 bar, it may not work properly. You can fix this by topping it up using an external filling hose. This guide will show you how to do it step by step, using simple instructions.
Table of contents
What Is an External Filling Loop?
An external filling loop is a silver flexible hose that connects your boiler to the cold-water supply. It lets you add water to your heating system when the pressure is too low.
How to Repressurise Your Boiler
Time needed: 5 minutes
Follow the below steps to repressurise your boiler
- Find the Filling Hose
Look under your boiler for a silver braided hose connecting two pipes. If it’s not connected, you might find it nearby and need to attach it yourself.
- Take Off the End Caps
Unscrew the small caps from the valve ends. You can do this by hand. Keep them safe—you’ll need to put them back later.
- Connect the Hose
Attach the hose to both valves. Hand-tighten the connections. No tools are needed.
- Open the Valves
Turn the cold water valve (usually the one connected to the mains) so it lines up with the pipe. Then slowly turn the other valve (usually with a black handle). Water will start flowing into your system.
- Watch the Pressure Gauge
Look at the pressure gauge on the boiler. When it reaches about 1.5 bar (in the green zone), turn both valves off.
- Disconnect the Hose Safely
Slightly loosen one end of the hose while covering it with your thumb. Then gently release the other end to let water drain into a container.
- Put the End Caps Back On
Screw the caps back onto both valve ends. This stop leaks and keeps your system safe and legal.
When to Call a Gas Safe Engineer
Call a Gas Safe registered engineer if:
- The valves are stuck or won’t turn.
- The boiler still loses pressure after refilling.
- You notice a leak anywhere in the system.
- You feel unsure or uncomfortable doing it yourself.
It’s always safer to ask a professional when in doubt.
Final Thoughts
You’ve just learned how to top up your Worcester Bosch boiler using an external filling loop. It’s a simple job you can do yourself in just a few minutes. Always check your boiler’s manual if anything seems unclear. If problems continue, don’t hesitate to call a professional. Stay warm and take care!
Frequently Asked Questions
Usually unconnected, this will loop upwards or downwards and will be externally located either beneath or beside and close to the boiler. There are 3 different methods, depending on which the installer has fitted, by which you can refill your system.
As its name suggests, this is attached and connected outside of your boiler to help repressurise it. It’s the most common type of filling loop and features a braided hose with two valves – one for controlling the flow of the water and the other to stop water from flowing back into the mains.
A Worcester Bosch filling loop is a part that only occurs on systems that deal with central heating. If the pressure in the central heating system has fallen too low, the filling loop enables the user to manually adjust the amount of water there.
Leaks in the system: If there are leaks in the pipes or the boiler itself, it can cause the pressure to drop. To fix this, locate and repair the leaks. Inadequate water supply: Ensure the boiler’s water supply is turned on, no valves are clogged or stuck, and there is enough water in the system.
