Watts 957-FS Serie Manual De Instalación & Mantenimiento página 5

Service Relief Valve
WARNING
!
Before to servicing the relief valve, it is mandatory to shut
down water system by closing both the inlet and outlet
shutoff valves and relieving pressure within the assembly by
opening test cocks No. 2, No. 3, and No. 4.
DO NOT REMOVE SPIDER BUSHING FOR SERVICING
1. Detach the activation module, if installed, from the flood sensor.
2. Use a #2 Phillips screwdriver to remove the sensor from the
relief valve.
3. Disconnect the hose from the bottom cover plate to the
relief valve.
4. An O-ring seals the relief valve body to the main housing.
Avoid tightening the connection beyond firm hand tightening.
The relief valve should be removable by unscrewing the relief
valve from the housing.
5. Remove the cover plate of the relief valve by detaching the
four connecting screws.
6. Remove the rubber diaphragm from the relief valve. Notice
how the diaphragm is configured so that it can be reinstalled
in the same manner. The hard rubber tab in the diaphragm fits
into a similar socket in the head of the piston. (See Figure A.)
7. Hold the relief valve in both hands with the threaded end
up and both thumbs on the head of the piston. Push up on
the piston until the piston shaft with the attached E-clip is
exposed. Remove the E-clip. (See Figure B.)
8. Remove the piston and spring from the relief valve housing and
thoroughly clean all parts including the diaphragm. Inspect all
rubber parts for damage; if any are damaged, replace with
new parts.
9. Reassemble the relief valve in the reverse order of these
instructions.
Figure A
Figure B
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