How to Add Water to Your Heating System and Why You Might Need To
A well-functioning heating system is essential for keeping your home warm during the colder months. However, if your boiler isn’t performing as it should—perhaps your radiators aren’t heating evenly, or you notice strange noises coming from the system—it might be due to low water pressure. In this post, we will explain why maintaining the correct water pressure is important, how to tell if your heating system needs more water, and how to top it up safely.
Why You Might Need to Add Water to Your Heating System
Heating systems, particularly those with a combi or system boiler, rely on a specific level of pressure to circulate hot water efficiently. Over time, small leaks, trapped air, or system maintenance (such as bleeding radiators) can cause the water pressure to drop. When this happens, your boiler may shut down or become less efficient, leading to poor heating performance.
Signs that your system needs more water include:
Radiators not heating properly
Boiler error codes or warning lights
A drop in water pressure, typically below 1 bar
Keeping the system pressure at the recommended level (usually between 1.0 and 1.5) ensures your boiler operates efficiently and helps prevent long-term damage.
How to Check Your Boiler’s Water Pressure
Before adding water to your heating system, check the pressure gauge on your boiler. Most modern boilers have a built-in pressure gauge located on the front panel. The needle should ideally point between 1 and 1.5 bar when the system is cold.
If the pressure is below 1 bar, it’s time to top up your system.
How to Add Water to Your Heating System
Follow these simple steps to safely add water to your heating system:
Turn off the boiler
Before topping up the pressure, switch off your boiler and allow it to cool down completely. This ensures safety and prevents accidental damage to the system.
Locate the filling loop
The filling loop is a silver, flexible hose with a valve at each end, usually located underneath the boiler. Ensure both ends are securely connected to the boiler.
Open the valves
Slowly open both valves on the filling loop. You should hear water flowing into the system. Keep an eye on the pressure gauge as the needle begins to rise.
Close the valves
Once the pressure reaches 1.5 bar, close both valves tightly to prevent overfilling. Over-pressurising the system can cause damage, so avoid exceeding the recommended level.
Remove the filling loop (if detachable)
If your filling loop is detachable, disconnect it and store it in a safe place. Ensure the valves are fully closed to prevent leaks.
Turn the boiler back on
Once the system is topped up, turn the boiler back on and check for any error codes. You may also want to bleed your radiators to remove any trapped air.
When to Call us
If you find that your heating system regularly loses pressure, or if you’re unsure about how to top it up safely, it’s best to call us to help. Persistent pressure loss can indicate a more serious problem, such as a leak in the system or a faulty pressure relief valve.
Maintaining the correct water pressure is crucial for keeping your heating system running efficiently. By knowing how to check and top up your boiler, you can avoid unnecessary breakdowns and stay warm throughout the winter. However, if in doubt, don’t hesitate to contact us for help by clicking here.