Draining a combi boiler involves a series of steps to safely remove the water from your heating system. Here's how to do it:
Steps to Drain Your Combi Boiler
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Turn off the Boiler and Power: The very first thing to do is switch off your combi boiler and disconnect it from the mains electricity supply. This prevents any accidental operation during the draining process.
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Allow the System to Cool: Let the hot water cool down completely. Draining a system with scalding hot water is extremely dangerous. Give it several hours to ensure it's safe.
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Locate the Drain Valve: The drain valve is usually located on a radiator at the lowest point in the system or sometimes directly on the boiler itself. It usually has a small nozzle and a valve that can be opened with pliers or a small wrench.
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Attach a Hose: Connect a hosepipe to the drain valve. Ensure it's securely attached to avoid leaks. Run the other end of the hosepipe to a suitable drain outside or a large container.
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Open the Drain Valve: Slowly open the drain valve to allow the water to flow out. Don't open it fully at once, as this could cause a surge of water.
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Vent the System: To allow air into the system and speed up the draining process, open the bleed valves on all the radiators, starting with the upstairs radiators and then moving to the downstairs ones. Keep an eye on the pressure gauge on the boiler; it should drop to zero.
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Consider Inhibitor: Once the system is drained, consider adding a corrosion inhibitor when refilling it. This helps protect the system from rust and scale build-up, extending its lifespan.
Important Considerations
- Safety First: Always prioritize safety. If you are unsure about any step, consult a qualified heating engineer.
- Water Disposal: Be mindful of where the water is draining to. Avoid draining into areas that could cause damage or pose an environmental risk.
- Refilling and Pressurizing: After draining, you will need to refill and re-pressurize the system. Make sure you know how to do this correctly to avoid damaging the boiler.
By following these steps carefully, you can drain your combi boiler safely and effectively. Remember to always prioritize safety and seek professional assistance if you're unsure about any aspect of the process.
