Bleeding Radiators

This playbook describes the step-by-step process for bleeding radiators to remove trapped air, thereby improving the overall heating efficiency within a home.

Step 1: Preparation

Turn on the heating to warm up the radiators. Ensure that the system reaches its maximum temperature before proceeding to identify which radiators require bleeding.

Step 2: Identify Radiators

Check each radiator for cold spots, particularly at the top, which indicates trapped air and thus, the need for bleeding.

Step 3: Turn Off Heating

Switch off the central heating to avoid more air from being drawn into the system and to allow the radiators to cool slightly before bleeding them.

Step 4: Protect Area

Place a cloth or a small container underneath the radiator valve to catch any water that might drip out during the bleeding process.

Step 5: Bleed Radiator

Using a radiator key or a flat-blade screwdriver, slowly turn the radiator valve counterclockwise to open it. Listen for a hissing sound, indicating that air is escaping. Once water starts to dribble out, close the valve by turning it clockwise.

Step 6: Check Pressure

After bleeding the radiators, check the pressure gauge on your boiler. If the pressure is too low, you may need to repressurise the central heating system according to the manufacturer's instructions.

Step 7: Test Heating

Turn the heating back on and check all the radiators to ensure they are heating up properly and to confirm that there are no more cold spots.

General Notes

Safety Reminder

Make sure the heating has cooled down enough to be safe to touch before bleeding the radiators to avoid burns.

Radiator Keys

Radiator keys are specialized tools designed for bleeding valves. If one is not available, a flat-blade screwdriver may suffice for some valve types.