How to Flush Your Central Heating System
Flushing your central heating system is an essential maintenance task that helps remove sludge, rust, and debris that can accumulate over time. Manually flushing your central heating can also prevent damage to your boiler and help improve its efficiency, therefore reducing your energy usage and bills long term. Sound good? You’re in the right place. Follow the below steps to successfully learn how to flush your central heating system like a pro!
Things you will need
Radiator bleed key
Garden hose
Old towels or rags
Container to catch water
Old clothes
Step 1
Safety First!
Before you begin your handywork, make sure the heating system is turned off and cooled down. Work in a well-ventilated area, put on old clothes and gloves to protect yourself from dirt and water, and lay down towels or rags to catch any spills.
Once the heating is system is cooled completely, identify the radiators in your home that you want to flush. It is recommended to start with your downstairs radiators and work your way up.
Step 2
Drain The Radiator
Now you’ve completed your prep, it’s time to drain the first radiator. Have a bucket ready to collect the water.
Firstly, you’re going to want to turn off both valves on your radiator and unscrew the nut that connects the radiator to the external pipe. If you find that the parts are stuck or seized, a spritz of WD-40® Multi-Use Product will help to loosen any buildup and release the parts with ease. The innovative formula effectively penetrates rust, dirt, and grime – and lubricates for easy removal.
Then, with your collection bucket in place, open the bleed valve and allow the water to flow freely out.
Step 3
Tilt The Radiator
When the water flow begins to slow down, it’s time to take the radiator off the wall. Unscrew the bolts connecting it to the wall, and slide it away. Then, tilt the radiator to empty out any remaining water.
Step 4
Clean Inside The Radiator
Now that the radiator is completely empty, you can clean out any sludge or buildup inside. This is an important step to flush your central heating system effectively!
To do this, simply attach a hosepipe to one end of the radiator, and flush out the inside, allowing it to drain out the other side. When the water coming out of the radiator runs clear, it is clean inside.
Step 5
Re-attach The Radiator
When you are happy with the cleanliness of your radiator, it’s time to attach it back to the wall. Simply slide the radiator back onto the wall, re-attach the bolts, re-connect the external pipe, and turn the valves back on. Your radiator should slowly refill.
Step 6
Bleed The Radiator
Finally, now your radiator is back in its place, it’s time to bleed it. Bleeding simply means getting rid of any air bubbles that are present inside the radiator. These air bubbles will not heat up when the heating is turned on, causing cold spots, and putting additional pressure on your boiler.
Using the bleed key, gently turn the bleed valve anti-clockwise until you hear a gentle hissing sound. Keep this open until a small amount of water trickles out – this is when you know that the radiator is now air free.
Step 7
Turn The Heating Back On
Now you have successfully flushed and bled your radiators, you can turn your heating back on and enjoy your freshly revived heating system.
Now you know!
So, there you have it! You have successfully manually flushed your central heating! Now you know how to successfully flush your central heating system, you can repeat this task whenever necessary – helping you save energy and money.
Looking to discover more ways WD-40® can help you around the home? Check out our other blogs.
The uses shown and described for WD-40 Multi-Use Product were provided to WD-40 Company by the users themselves. These uses haven’t been tested by WD-40 Company and do not constitute a recommendation of suggestion for use by WD-40 Company. Common sense should be exercised whenever using WD-40 Company products. Always follow the instructions and take heed of any warnings printed on the packaging.
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