Draining the central heating system
Draining the central heating system
A fully pumped central heating system can be flushed to enable work to be executed. To fit a thermostatic metal radiator valve or replace a failed heating radiator are two examples. Your engineer will normally be performing list has although some householders do have the confidence to try this themselves.
Most often cleaning the radiators is in the main grounds for doing at this task. The first measure you should take is to turn off the gas boiler and central heating pump. To successfully finish this job you also need to check that no more water enters the gas central heating system.
The tank in the attic is used to normally top up the system with water. A standard ballvalve 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 shuts the valve. As the water level falls, say through Flushing, the ball drops in the tank venting the valve and allowing more water to enter the gas central heating system. This is what needs to be contained when Cleaning your metal radiator. Placing a small plank of wood across the water tank preventing the ball valve from moving will stop further water going into the heating system.
Once you have finished the above run a hosepipe from an outside clear to the outlet of at the bottom of one of your radiators. The water from your radiator will current through the hose pipe and out of your radiator system. The hosepipe needs to be connected to the lowest point in your gas central heating system which will be one of the ground floor radiators. Check now that no water is moving into the gas central heating system and that the radiators are fully flushed before you do any further work.
By opening the bleed valves in the radiators on the top story you will help air to enter the central heating system and hurry up the Flushing process. When all the water has gone you can now commence work on the system.