The way to empty a central heating system
The way to empty a central heating system
Emptying a fully pumped gas heating system makes it easier to work on the system. To replace the gas boiler or a heating radiator is a standard cause. Your engineer will normally be performing list has although some householders do have the confidence to try this themselves.
Cleaning the radiators is the most popular driver of this action. The first step you should take is to turn off the heating boiler and central heating pump. It is also important that you do not let any additional water into the central heating system while you flush it.
Your gas heating system is topped up with water through the header cystern. A common ball valve is used in the expansion cylinder similar to that in a toilet. As the water reaches maximum level the ball floats on the surface and closes the valve. As the water level falls, say through Flushing, the ball drops in the water tank opening the valve and allowing more water to enter the heating system. To fully drain the central heating system this top up process will need to be stopped. To prevent any more water getting in the valve needs to be off.
When all these safeguards have been performed, you should attach a hose pipe to the part of your metal radiator known as the outlet and run the end of the hosepipe outside. Water can now enter the external clean my flowing through the hose out of the radiator valve. To clear your whole central heating system you need to connect this hosepipe to one of the ground floor radiators, the lowest ones in the house. Check now that no water is getting in the central heating system and that the radiators are fully drained before you do any further work.
If you need to end this process rapidly you can also vent the bleed valves on the heating radiators on the top floors. You can commence work on the heating system once all the water has emptied out.