Heating systems can be drained
Heating systems can be drained
A fully pumped gas central heating system can be emptied to enable work to be carried out. To totally flush the system of slime and contaminants might be one such instance. This is often carried out by the heating engineer during repair or extension work although some experienced homeowners have been known to flush their own heating systems.
The main cause for most individuals for Emptying their gas heating system is to clean the heating radiators. For this project the first activity will be to switch off the gas fired boiler and water heating pump. To successfully complete this job you also need to see to it that no more water enters the gas central heating system.
gas heating systems are normally topped up via a tank in the attic. This has a ball-valve that is the same as the one seen in your toilet cystern. Rising water levels in the cylinder mean that the valve is shut as the ball floats higher on the water surface. As the water level falls, say through Flushing, the ball drops in the water tank venting the valve and allowing more water to enter the gas heating system. Water will need to be prevented from entering the gas heating system if the Cleaning process is to complete. One of the better ways to contain this is by placing a piece of wood across the cystern and splicing the value arm to it, which will close this valve.
Now take a hose emptying into an outdoors clean and connect this to the outlet valve on the bottom of your radiator. The water from your radiator will passage through the hose and out of your radiator system. To empty your whole gas central heating system you need to attach this hosepipe to one of the ground floor heating radiators, the lowest ones in the house. Be patient and ensure that all water has emptied from the central heating system and no more water is getting in before you begin any further work.
By opening the bleed valves in the radiators on the top floor you will help air to enter the gas central heating system and speed up the Emptying process. When the water is drained off you are clear to work on your radiator.