11
Customer Service
(704) 841-6000
backflow.apollovalves.com
ES1600 REV A.
BFMMRP4ALBF
D. RELIEF VALVE MAINTENANCE, 10-12”
Note: See Figure 10.
1. Unscrew the sensing hose from the relief valve (RV) cover nipple (sensing hose is not shown).
2. The RV can be serviced while still attached to the valve or it can be removed (rarely needed). To remove the RV, unscrew the two 3/4” bolts securing
the RV to the valve body. NOTE: When removing the RV from the valve body, take care not to damage flow divider (See Figure 10). The shroud does
not need to be removed to service the RV.
3. Remove the RV cover by removing the eight (8) 1/2” bolts.
4. Remove the RV cartridge by grasping the diaphragm plate and pulling straight out. A bushing o-ring may remain in the body.
5. Ensure this o-ring is not damaged.
6. Inspect the RV seat disc for debris or damage. To clean or replace the RV seat disc, remove the 3/8” screw on the seat disc washer. The RV disc may
be flipped over for a temporary repair, but should be replaced if damaged. Replace the seat disc, seat disc washer, and 3/8” screw.
7. Insert the RV module into the valve body.
8. Replace cover and bolts.
9. Inspect sensing hose and replace if damaged.
10. Reinstall sensing hose to RV cover nipple.
If it is necessary to disassemble the RV module and/or remove the RV seat:
1. Remove the RV module as described above.
2. Remove the 5/8” screw on the diaphragm plate. Use caution as this will disengauge the spring.
3. Remove the 3/8” screw on the seat disc washer.
4. Inspect all components for damage, paying particular attention to the diaphragm, seat disc, o-rings, and stem. If any of these components are worn
or damaged, they should be replaced.
5. Lubricate the stem, stem o-ring, and RV seat o-ring with Apollo® supplied lubricant, DOW 111 or equal. Reassemble RV cartridge.
6. Remove the RV seat by grasping the cage and pulling straight out. A flat screwdriver may be necessary to aid in removal.
7. Inspect the seat and seat o-ring for damage. If damaged, they should be replaced.
8. Insert the seat into the RV body. Ensure that it is fully seated and that the seat’s tab aligns with the notch in the RV body.
9. Ensure the bushing o-ring is positioned in the RV body, then insert the assembled RV cartridge into the valve body.
10. Replace cover and bolts.
11. Inspect sensing hose and replace if damaged.
12. Reinstall sensing hose to RV cover nipple.
IV.
MAINTENANCE INSTRUCTIONS - 10-12”
