29
Maintenance Procedure - Check Valve Cartridges
Hot water entering the cold supply, or vice versa, indicates that immediate attention
is necessary. This is carried out by removing and cleaning, or renewing as
necessary, the two check valves.
1.
Turn the isolation screw on the isolator assemblies through 90
o
(refer to
Figure
9
) to isolate the water supplies to the valve. Open an outlet fitting to release
pressure and to assist the draining of residual water.
2.
Loosen the isolator grub screws and remove the isolator assemblies from the
inlet elbows.
Note!
If necessary, loosen the two grub screws that hold the valve body onto the
backplate and undo the outlet compression fitting. This is so that you can lower
the body away from the backplate. This will give enough clearance to remove the
isolator assemblies from the inlet elbows.
3.
Remove the inlet elbow grub screws and remove the inlet elbows.
4.
Unscrew and remove the check valve housings.
5.
Push out the check valves.
The check valve is not a serviceable item, so any apparent wear or damage
will require its renewal.
6.
Re-assembly into the valve is a reversal of the above procedures.
7.
Turn the isolation screw on the isolator assemblies through 90
o
(refer to
Figure
9
) to restore the water supplies to the valve and check for leaks.
Check Valve Cartridges
Figure 9
Backplate
Isolation Screw
Isolator
Assembly
Valve Body
Check Valve Housing
Check Valve
Grub Screw
Inlet Elbow
Isolator
Open
Isolator
Closed
Grub Screw
