To remove an airlock from a gravity-fed heating system, you typically need to bleed the radiators. Here's a breakdown of the process:
Bleeding Radiators to Remove Airlocks
Bleeding radiators is the most common method for removing trapped air in a gravity-fed heating system. Air can get trapped in the highest points of the system, often the radiators, causing them to be cold or partially heated. Here's how to do it, incorporating the steps from the reference:
Step-by-Step Guide
| Step | Action | Reasoning |
|---|---|---|
| 1 | Turn off your central heating and wait about 20 minutes for the system to cool down. | This prevents scalding and reduces pressure, making bleeding easier. |
| 2 | Lay a dry cloth or towel beneath the radiator's bleed valve. | Catches any escaping water. |
| 3 | Use a radiator key to slowly open the bleed valve, turning it anti-clockwise. | This allows the trapped air to escape. |
Additional Considerations
- Listen for a hissing sound. This indicates air is escaping. Once it stops hissing and water starts to trickle out, you have removed the air.
- Close the valve. Once water starts to escape, use your radiator key to quickly close the valve by turning it clockwise.
- Check the system pressure. After bleeding all necessary radiators, check the system pressure and top up with water if required.
- Repeat if necessary. You may need to repeat the process if the issue persists, or bleed the radiators again later.
- Start from the lowest radiator. Begin bleeding the radiators on the ground floor first, and then move your way up through the house as air will naturally rise within the system.
Why Air Gets Trapped
Air can get into a heating system for a variety of reasons:
- Initial filling: Air can be trapped when the system is first filled with water.
- Leaks: Leaks, even small ones, can allow air to enter the system.
- Corrosion: Corrosion inside the radiators can create gases that accumulate as airlocks.
- Water top-ups: Frequent filling of the system with fresh water can introduce air.
When to Seek Professional Help
If bleeding the radiators doesn't solve the problem, or you find yourself needing to bleed them very often, it might be indicative of a bigger issue. Consider seeking help from a qualified heating engineer if:
- The problem persists despite repeated bleeding.
- You notice leaks in the system.
- Your radiators are consistently cold or only partially heating.
- You suspect a problem with the pump or other components.
By following these steps, you should be able to effectively remove airlocks from your gravity-fed heating system. Remember to always be cautious when dealing with hot water and heating systems.
