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Service
Manual | 38. Drain valve |
5 | 9002 | 1 | 38 |
Type | Edition | Page |
Description1
Fig. The drain valve utilises the water pressure in the
1cold water inlet to close the valve. A hose (1) connects the water inlet and the control valve (2). When the control valve is activated, it opens and allows water to pass through the supply main (3) which is connected to the drain valve. The water pushes up a rubber diaphragm (4) and a piston (5) by means of a pressure plate (6) which closes the rubber diaphragm (7) on the valve.
When the control valve shuts off the water pressure leading to the drain valve, the springs (8) pull back the piston. The return water passes through the control valve to the drain via the return hose and is drained (9).
Fault tracing
Drain valve does not close
Check that:
•there is voltage supply to the control valve (2).
•hoses and control valve are not blocked. This is done by disconnecting the supply main (3) to the drain valve and activating the control valve.
•the rubber diaphragm (4) is ok.
•the piston (5) is not jammed.
Drain valve does not open
Check that:
• the return hose (9) is not blocked.
3 2 1
9
7
6
8
5
4
G115
• the piston (5) is not jammed.