Apollo RP4A Instruction manual

INSTALLATION, OPERATION & MAINTENANCE MANUAL
2-1/2” - 12” Reduced Pressure Principle | Reduced Pressure Detector Assembly
RP4A | RPLF4A | RPDA4A | RPDLF4A | RPDA24A | RPDA2LF4A
ES1600 IOM BFMMRP4ALBF rev.a

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INSTALLATION, OPERATION & MAINTENANCE
MANUAL
SECTION DESCRIPTION PAGE
Reduced Pressure Principle Backflow Preventer RP4A / RPLF4A
I Description and Operation 3
II Installation 3
III Troubleshooting Guide 4
IV Maintenance Instructions (RP/RPDA mainline) 5
2-1/2” - 6” 5-7
8” - 12” 7-11
V Testing Procedures 12-13
Reduced Pressure Detector Assembly RPDA4A / RPDALF4A & RPDA24A / RPDA2LF4A
VI Description and Operation 14
VII Installation 14
VIII Maintenance Instructions - Bypass Single Check (Type 2) 23
IX Maintenance Instructions - Bypass RP (Type 1) 36
PARTS LIST
2-1/2” - 6” RP & RPDA (Mainline) 16-17
8” - 12” RP & RPDA (Mainline) 13-14
2-1/2” - 12” RPDA2 (Type 2) Bypass Single Check 15
2-1/2” - 12” RPDA (Type 1) Bypass RP 28
REPAIR KITS
2-1/2” - 6” Check Valves 18
8” - 12” Check Valves 18
2-1/2” - 6” Relief Valves 21
8” - 12” Relief Valves 21
Bypass Single Check (RPDA Type 2) 22
Bypass RP (RPDA Type 1) 35
Bypass Line Kits 23-33
Shut-o Valves 37-39
TABLE OF CONTENTS

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ES1600 REV A.
BFMMRP4ALBF
FIGURE 1
The Reduced Pressure Principle (RP) device consists of two independently-acting, spring-loaded check valves, together with a hydraulically
dependent, mechanically independent pressure differential relief valve, located in the zone between the check valves. Two resilient seated
shut-off valves and four test cocks complete the assembly.
The first check is designed to maintain a minimum of 5 psi across the check valve. The second check is designed to maintain a minimum of
1 psi across the check valve during normal operation. The relief valve operates on a differential pressure. Supply pressure on the upstream
side of the first check valve acts against the diaphragm to close the relief valve during normal operation. In the event of back-pressure, the
relief valve will open to maintain the pressure in the “zone” at least 2 psi less than the inlet pressure.
I. DESCRIPTION AND OPERATION
II. INSTALLATION
1. The RP must be installed in an accessible location to facilitate periodic field testing and maintenance.
2. The location selected should have adequate drainage for relief valve discharge. The device should never be placed where it may be submerged
in standing water.
3. Flush all upstream piping thoroughly to remove foreign matter prior to installing the device.
4. The device should be installed in the horizontal position. A clearance between the lower most portion of the device and flood grade or floor should
be provided for ease of maintenance.
5. If shut-off valves are provided separately, they must include tapped bosses for attachment of the sensing hose, the #1 test cock, and the #2 test
cock. Contact the factory for installation instructions.
6. After installing the assembly and with downstream or #2 shut-off valve closed, pressurize the device and bleed air through test cock #4. Then
open #2 shut-off valve.
OTHER INSTALLATION TIPS
• The installation location should have adequate drainage for relief valve discharge. The device should never be placed where it may be sub-
merged in standing water. Do not install in areas subject to freezing without using a properly designed enclosure.
• As in any piping system, provisions should be made to minimize water hammer and pressure rise due to thermal expansion, as these conditions
can create damaging and dangerously high internal pressures.
• A “Y” strainer can be installed just upstream of the RP assembly to eliminate any debris from entering the device and fouling the check and/or
relief valve. Note: Strainers are normally not allowed on fire protection systems. Check with local authorities.
TC: TEST COCK
CV: CHECK VALVE
Note: Pressures are for illustrative purposes only and are not necessarily indicative of any actual valve.

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III. TROUBLESHOOTING
SYMPTOM CAUSE CORRECTIVE ACTION
Relief valve continuously discharges during
no-flow condition.
1. #1 check valve fouled with debris.
2. #2 check valve fouled with debris
coupled with a back-pressure condition.
3. #1 check poppet stem not moving freely
in guide (or #2 check poppet during a
back-pressure condition
1. Inspect and clean seat disc and seat
2. Inspect and clean seat disc and seat.
3. Inspect for debris or deposit on poppet
stem or guide.
Relief valve discharges continuously during
flow and no-flow conditions.
1. Relief valve fouled with debris.
2. Damaged diaphragm (allows water to
pass through from inlet to zone).
3. Sensing passage to inlet side of
diaphragm plugged.
4. #1 check poppet stem not moving freely
in poppet guide.
5. 1st and 2nd check springs are in
wrong check.
1. Inspect and clean relief valve seat disc
and seat.
2. Replace diaphragm.
3. Inspect and clean passage in cover and
body.
4. Inspect for debris or deposits on poppet
stem or guide.
5. Switch springs to proper check location.
Relief valve discharges intermittently in a
“spitting” action during no-flow condition.
1. Pressure fluctuations or water hammer
from supply.
1. Eliminate or reduce supply pressure
fluctuations.
Relief valve does not open during test No. 1. 2. #2 shut-o valve not closed completely.
3. Test equipment improperly installed.
4. Plugged sensing line.
1. Close #2 shut-o valve or inspect for
possible through leakage.
2. Recheck test procedure.
3. Clean sensing line.
#2 check valve fails to hold back-pressure. 1. #2 shut-o valve not closed completely.
2. #2 check valve fouled with debris.
3. #2 check poppet stem not moving freely
in guide.
1. Close #2 shut-o valve or inspect for
possible through leakage.
2. Inspect and clean seat disc and seat.
3. Inspect for debris or deposits on poppet
stem or guide.
Pressure dierential across #1 check valve is
low during field test No. 3 (does not meet 5
PSID minimum).
1. #1 check valve fouled with debris.
2. Upstream pressure fluctuations causing
inaccurate gauge reading.
3. #1 check poppet stem not moving freely
in guide.
1. Inspect and clean seat disc and seat.
2. Eliminate pressure fluctuations.
3. Inspect for debris or deposits on poppet
stem or guide.

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ES1600 REV A.
BFMMRP4ALBF
FIGURE 2 FIGURE 3
(SENSING HOSE NOT SHOWN)
Open test cocks #2, #3, and #4 to relieve pressure from the device. Both shut-off valves must be closed.
A. CHECK REMOVAL
Note: If the first check disc needs only to be cleaned, it is not necessary to remove the entire check module from the valve body. See
the next section, “Check Maintenance”, for seat disc cleaning instructions.
1. Remove the cover clamp by backing off the reusable locknut until the latch can be disengaged from the T-bolt. Pull the clamp apart and slide
away from the valve. (See Figure 2)
2. Lift off the cover. A flat screwdriver will aid in lifting the cover out of the body. Screwdriver slots are provided on the perimeter of the cover. The
first check must be removed first and then the second check may be removed.
3. Remove the check-retaining clip by pinching the clip ears together. This will disengage the clip from its groove. Remove clip and check-retaining
ring. Pull check module straight out of body. The check module is sealed in place with an o-ring. (See Figure 3)
B. CHECK MAINTENANCE
If only cleaning of the first check is necessary, simply remove the three (3) reusable locknuts for 2-1/2” & 3” valves / four (4) nuts for 4” & 6”
valves on the black plastic disc retainer (See Figure 4). SUGGESTION: Place a rag over the relief valve opening inside the valve body to prevent
the locknuts from falling into the relief valve. Remove the check handle and washer and lift the disc retainer and disc out of the body. Rinse
the disc with clean water or replace if necessary. The disc may be flipped over for a temporary repair, but should be replaced if damaged.
Replace the disc, disc retainer, washer, handle, and nuts. Do not over tighten locknuts.
NOTE: The springs are factory installed and should not be removed or adjusted. Serious injury could occur if springs are disassembled.
IV. MAINTENANCE INSTRUCTIONS - 2-1/2” – 6”
FIGURE 4
2-1/2” - 6” SIZES

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C. RELIEF VALVE MAINTENANCE
1. Unscrew the sensing hose from the nipple (sensing hose is not shown). (See Figure 5)
2. The RV can be serviced while still attached to the valve or it can be removed (rarely needed).
3. Remove the clamp by backing off the nut until the latch can be disengauged from the T-bolt. Pull the clamp apart and slide away from the RV.
4. Remove the RV cover.
5. Remove the RV module by grasping the diaphragm plate and pulling straight out.
6. Inspect the RV seat disc for debris or damage. To clean or replace the RV seat disc, remove the 5/16” 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 5/16” screw.
7. Lubricate the bushing o-ring with Apollo® supplied lubricant, Dow 111 or equal, and insert the RV module into the valve body.
8. The RV diaphragm has a rubber bead that fits into a groove in the RV body. Ensure the diaphragm bead is seated properly in the RV body before
installing the RV cover.
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 5/16” screw on the diaphragm plate. Use caution as this will disengauge the spring.
3. Remove the 5/16” 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.
6. Reassemble RV module.
7. Remove the RV seat by grasping the cage and pulling straight out. A flat screwdriver may aid in removal.
8. Inspect the seat and seat o-ring for damage. If damaged, they should be replaced.
9. Insert the seat into the RV body. Ensure that it is fully seated.
10.Lubricate the bushing o-ring with Apollo® supplied lubricant, Dow 111 or equal and insert the assembled RV module into the valve body. Ensure the
diaphragm bead is seated properly before installing the RV cover.
11. Replace the cover and clamp.
12.Inspect the sensing hose and replace if damaged.
13.Reinstall the sensing hose to the nipple.
FIGURE 5
2-1/2” - 6” SIZES
IV. MAINTENANCE INSTRUCTIONS - 2-1/2” – 6”

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ES1600 REV A.
BFMMRP4ALBF
8” – 12” SIZES
Open test cocks #2, #3, and #4 to relieve pressure from the device. Both shut-off valves must be closed.
IV. MAINTENANCE INSTRUCTIONS - 8” – 12”
NOTE: On 10” & 12” models, the flow divider (FD) must be removed before the checks are removed. To remove the FD, remove the ¼”
nut holding it in place. Then rotate the FD 90° and lift up and out of the valve body. Pay attention to which side of the body the FD is
attached. The FD’s tab should be oriented on the same side as the cover of the relief valve body. If the relief valve needs to be turned
180°, the FD must also be rotated 180°.
A. CHECK REMOVAL
Note: If the first check disc needs only to be cleaned, it is not necessary to remove the entire check module from the valve body. See
the next section, “Check Maintenance”, for disc cleaning instructions.
1. Take off the cover coupling by removing the two bolts and nuts.
2. Lift off the cover. The gasket may remain on the valve body. See Figure 6. Note: The 10” & 12” valves are equipped with lifting tabs for cover lifting
only. This tab should not be used to lift the entire valve.
3. Remove the six (6) reusable locknuts for 8” valves / eight (8) nuts for 10” & 12” valves on the check seat with a 3/4” socket and ratchet.
SUGGESTION: Place a rag over the relief valve opening inside the valve body to prevent the locknuts from falling into the relief valve.
4. Slide the entire check module off the body studs and remove from body (See Figure 7).
Either check may be removed without disturbing the other (8” – 12” valves only).

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FIGURE 8
8” - 12” SIZES
IV. MAINTENANCE INSTRUCTIONS - 1/2” – 6”
FIGURE 6 FIGURE 7
B. CHECK MAINTENANCE (CAN BE ACHIEVED WITHOUT REMOVING ENTIRE CHECK.)
If only cleaning of the first check is necessary, simply remove the six (6) reusable locknuts for 8” valves / eight (8) nuts for 10” & 12” valves on
the black plastic disc retainer (See Figure 8). Remove the check handles and washers and lift the disc retainer and disc out of the body. Rinse
the disc with clean water or replace if necessary. The disc may be flipped over for a temporary repair, but should be replaced if damaged.
Replace the disc, disc retainer, washer, handle, and nuts. Do not over tighten locknuts.
NOTE: The springs are factory installed and should not be removed or adjusted. Serious injury could occur if springs are disassembled.

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BFMMRP4ALBF
C. RELIEF VALVE MAINTENANCE, 8”
Note: See Figure 9.
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 5/8” bolts securing
the RV to the valve body.
3. Remove the RV cover by removing the eight (8) 3/8” bolts.
4. Remove the diaphragm.
5. Remove the RV cartridge by grasping the diaphragm plate and pulling straight out. A bushing o-ring may remain in the body.
6. Ensure this o-ring is not damaged.
7. Inspect the RV seat disc for debris or damage. To clean or replace the RV seat disc, remove the ¼” 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 ¼” screw.
8. Insert the RV module into the valve body.
9. Replace diaphragm, cover, and bolts.
10.Inspect sensing hose and replace if damaged.
11. 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 1/4” screw on the diaphragm plate. Use caution as this will disengauge the spring.
3. Remove the 1/4” 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.
9. Ensure the bushing o-ring is positioned in the RV body, then insert the assembled RV cartridge into the valve body.
10.Replace diaphragm, cover, and bolts.
11. Inspect sensing hose and replace if damaged.
12.Reinstall sensing hose to RV cover nipple.
IV. MAINTENANCE INSTRUCTIONS - 8”

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COVER BOLTS
COVER
DIAPHRAGM
RELIEF VALVE
CARTRIDGE
RV SEAT
RV SEAT
O-RING
BUSHING
O-RING
RV
BODY
1/4"
SCREW
1/4" SCREW
DISC WASHER
DISC
STEM
STEM O-RING
BUSHING
SPRING
DIAPHRAGM
PLATE
BOLT
STEM O-RINGS
BUSHING
SPRING
DIAPHRAGM
PLATE
RV
BODY
RV SEAT
O-RING
RV SEAT
BUSHING
O-RING
RELIEF VALVE
CARTRIDGE
COVER
COVER BO
LTS
NIPPLE
SCREW
DISC WASHER
DISC
STEM
DIAPHRAGM
PLATEDIAPHRAGM
SHROUD
1/4"
SCRE
W
IV. MAINTENANCE INSTRUCTIONS - 2-1/2” – 6”
FIGURE 9
8”
FIGURE 10
10” -12”

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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”

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V. TESTING PROCEDURES
NOTE: This 3 valve test kit procedure may not be approved in all jurisdictions. Consult your local water purveyor for acceptable test
procedures. See Figure 10 for test schematic.
TEST NO. 1
PURPOSE: TO TEST OPERATION OF THE PRESSURE DIFFERENTIAL RELIEF VALVE.
REQUIREMENT:
The pressure differential relief valve must operate to maintain the zone between the two check valves at a minimum of 2 psi less than the
supply pressure.
PROCEDURE:
1. Open test cock (TC) #4 to establish flow through the RP. Flush TCs in the following order taking care not to dump the relief valve. Open and close
TC #1. SLOWLY open and close TC #2. Open and close TC #3. Close test cock #4. Install appropriate adapters in TCs.
2. Connect the high (left) hose to TC #2. Connect the low (middle) hose to TC #3. Fully open the bypass (right) valve.
3. Slowly open TC #2. Bleed the high side through the bypass hose by opening the high valve. Close the high valve.
4. Slowly open TC #3. Bleed the low side through the bypass hose by opening the low valve. After the pointer on the gauge reaches the upper end of
the scale, close the bypass and low valves.
5. Close the No. 2 shutoff valve and observe the pressure drop across check valve No. 1. If the pressure drops until the relief valve discharges
continuously, check valve No. 1 is leaking and must be cleaned or repaired before continuing.
6. Open the high valve.
7. Open the low valve no more than one-quarter (1/4) turn.
8. Watch the pointer on the gauge drop slowly to the opening point of the relief valve and record the reading. If the relief valve does not open, go
to step 10.
9. Close the high and low valves on the gauge and go to test No. 2.
10.The No. 2 shutoff valve may be leaking. Reopen and close No. 2 shutoff valve to attempt a better shutoff. Repeat steps 6 through 8. If the relief
valve does not open, a bypass hose is required (not to be confused with the bypass hose on the gauge).
11. Large leaks may require a garden hose.
12.Attach the bypass hose to TC #1. Bleed hose by opening TC #1. Close TC #1.
13.Connect the bypass hose from TC #1 to TC #4.
14.Open TC #1 to pressurize the hose.
15.Slowly open TC #4. Repeat steps 6 through 8. If the relief valve still does not open, the leaky No. 2 shutoff valve must be repaired.
TEST NO. 2
PURPOSE: IS CHECK VALVE NO. 2 TIGHT AGAINST BACK PRESSURE?
NO BYPASS HOSE USED IN TEST 1
1. Bleed gauge bypass hose by opening the high and bypass valves. Close the bypass valve.
2. Attach the bypass hose to TC #4. Open TC #4.
3. Loosen the low side hose at TC #3 to re-establish the normal reduced pressure within the “zone”. Re-tighten the low hose at TC #3.
4. Open the bypass valve. If the differential pressure stabilizes above the relief valve opening point, check valve No. 2 is recorded as “tight”. Proceed
to test No. 3. If the reading falls to the relief valve opening point, check valve No. 2 is noted as “leaking” and test No. 3 cannot be completed.
BYPASS HOSE USED IN TEST 1
5. Leave the bypass hose connected between TCs #1 and #4. Leave TCs #1 and #4 open.
6. Open the low and bypass valves allowing the pointer to reach the upper part of the scale.
7. Close the low and bypass valves.
8. If the differential pressure stabilizes above the relief valve opening point, check valve No. 2 is recorded as “tight” (proceed to test No. 3). If the
reading falls to the relief valve opening point, check valve No. 2 is recorded as “leaking” and test No. 3 cannot be completed.
V. TESTING PROCEDURES

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TEST NO. 3
PURPOSE: IS THE STATIC PRESSURE DROP ACROSS CHECK VALVE NO. 1 MAINTAINED AT LEAST 3 PSI ABOVE THE RELIEF VALVE OPENING
POINT?
NO BYPASS HOSE USED IN TESTS 1 AND 2
1. Close the high and bypass valves. Close TC #4 and disconnect gauge bypass hose.
2. Open the low and bypass valves allowing the pointer to reach the upper end of the scale. Close the low and bypass valves.
3. Allow the gauge reading to stabilize. Record this reading as the static pressure drop across check valve No. 1.
BYPASS HOSE USED IN TESTS 1 AND 2
1. Open the low and bypass valves allowing the pointer to reach the upper end of the scale. Close the low and bypass valves.
2. Allow the gauge reading to stabilize. Record this reading as the static pressure drop across check valve No. 1.
TESTING PROCEDURE FOR SINGLE CHECK ON RPDA TYPE 2 BYPASS:
Note: The first check of the mainline valve is also the first check of the bypass assembly and the test results for the first mainline check
should be recorded as the first check of the bypass assembly. If the local water authority requires a second test for the first check,
perform the test again and record the results. The second check is the single check on the bypass line. (See page 14 for test cock
locations.)
1. Flush water through the bypass line test cocks to eliminate foreign material.
2. To test the bypass single check, connect the “high” side hose to the first test cock on the bypass line (upstream of single check valve). Hold the
“low” side hose level with the gauge.
3. Close the inlet shut-off valve on the mainline and bypass line. The single check valve must hold at least 1.0 psid.
WRAP UP:
CLOSE ALL TEST COCKS. OPEN NO. 2 SHUT-OFF VALVE. DRAIN GAUGE.
V. TESTING PROCEDURES
FIGURE 11

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The Reduced Pressure Detector Assembly (RPDA Type 1) contains a mainline RP incorporating two independently acting, spring-loaded check
valves with a diaphragm-actuated spring-loaded relief valve located between the checks and a bypass line consisting of an approved RP
assembly and a water meter. The RPDA Type 2 contains a mainline RP and a bypass line consisting of a single check valve and a water meter
(A Type 2 bypass utilizes the first check of the mainline as the first check of the bypass and the single check on the bypass as the second
check). Each device is equipped with test cocks for periodic field testing and is normally supplied with inlet and outlet shut-off valves. NOTE:
UL and FM installations must include indicating type shut-off valves.
During no flow conditions, the mainline and bypass check valves will remain closed. If there is a low flow demand (up to a minimum of 2
gpm) of water downstream, the flow is routed through the water meter to monitor such consumption. If the downstream pressure increases
above the supply pressure or there is a reduction in the inlet pressure, the mainline and bypass check valves will close to prevent backflow.
VI. DESCRIPTION AND OPERATION
VII. INSTALLATION
1. The RPDA must be installed in an accessible location to facilitate periodic field testing and maintenance.
2. Flush all upstream piping thoroughly to remove foreign matter prior to installing the device.
3. The device must be installed in the horizontal position. A clearance of 12” to 30” between the lower most portion of the device and flood grade or
floor should be provided for ease of maintenance.
4. If shut-off valves are provided separately, they must include tapped bosses for attachment of the sensing hose, bypass piping, the #1 test cock,
and the #2 test cock. Contact the factory for installation instructions.
5. After installing the assembly and with downstream (#2) shut-off valve closed, pressurize the device and bleed air through test cock #4. Then
open #2 shut-off valve.
OTHER INSTALLATION TIPS
• The installation location should have adequate drainage for relief valve discharge. The device should never be placed where it may be sub-
merged in standing water. Do not install in areas subject to freezing without using a properly designed enclosure.
• As in any piping system, provisions should be made to minimize water hammer and pressure rise due to thermal expansion, as these conditions
can create damaging and dangerously high internal pressures.
• A “Y” strainer can be installed just upstream of the RP assembly to eliminate any debris from entering the device and fouling the check and/or
relief valve. Note: Strainers are normally not allowed on fire protection systems. Check with local authorities.

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ES1600 REV A.
BFMMRP4ALBF
RPDA24A TYPE 2
RPDA2LF4A TYPE 2
RPDA4A TYPE 1
RPDALF4A TYPE 1
RPDA BYPASS TYPES

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RP4A, RPLF4A
RPDA4A, RPDALF4A (MAINLINE)
RPDA24A, RPDA2LF4A (MAINLINE)
PART NUMBER DIAGRAM - 2-1/2” - 6”

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backflow.apollovalves.com
ES1600 REV A.
BFMMRP4ALBF
RP4A / RPDA4A (MAINLINE) / RPDA24A (MAINLINE) PARTS LIST
RPLF4A / RPDALF4A (MAINLINE) / RPDA2LF4A (MAINLINE) PARTS LIST
ITEM # DESCRIPTION QTY. PART NUMBER
2-1/2” 3” 4” 6”
1Shut-o Valve 2 See Pages 26 & 27
2Reducer Bushing 2K-4605-00 N/A
3Nipple 2K-3406-00 K-3412-00
4 Test Cock, FxF 2 77CLF-103-10 77CLF-104-10
5Valve Body 2Consult Factory
6 Screw, 3/8-16 x .63" Lg 2 B-1921-00
7 Relief Valve Sub-Assy 1 W-9664-05
8 O-ring, RV Port 1 D-4866-00
9Plug, 1/2" NPT 2K-4594-05
10 Coupling 2W-5237-00 W-5238-00 W-5239-00 W-5240-00
11 Test Cock, MxF 1 77CLF-803-10 77CLF-804-10
12 Second Check Module 1W-9857-05 W-9667-05 W-9671-05
13 Cover Clamp 1W-9293-00 W-9183-00 W-9221-00
14 Retaining Nut 1C-2635-00 C-1756-00
15 O-ring, Test Cock 1 D-4892-00 D-3904-00
16 O-ring, Cover 1D-4976-00 D-4870-00 D-5001-00
17 Cover, Inner 1F-3900-00 F-3864-00 F-3865-00
18 Cover, Outer 1E-2903-00 E-2865-00 E-2866-00
19 Test Cock, Cover 1 77CLF-803-A0 77CLF-804-A0
20 RP First Check Module 1 W-9855-05 W-9666-05 W-9670-05
21 Check Retaining Ring 2E-2960-00 E-2868-00 E-2869-00
22 Check Retaining Clip 2L-8063-00 L-7 9 9 6 - 0 0 L- 8 0 37- 0 0
23 Seat/Spring Sub-Assy 1W-9715-05 W-9717-05 W-9719-05
24 Check Seat O-ring 1 D-5171-00 D-4869-00 D-5000-00
25 Seat Disc 1 D-4958-00 D-4862-00 D-4890-00
26 Disc Retainer 1L-7800-00 F-3862-00 F-3863-00
27 Washer (QTY) E-2905-00 (1) E-2920-00 (1) E-2878-00 (4)
28 Handle (1st Chk Only) 1 H-3814-00 H-3792-00 H-3793-00
29 Locknut (QTY) C-1900-00 (3) C-2052-00 (4) C-2053-00 (4)
30 Nipple, 1/2" Close 1K-3460-00
31 Elbow, Street, 1/2" 1 K-4600-00
32 Sensing Hose 1W-9898-00
33 RV Body 1 Q-6945-05
34 Seat O-ring 1 D-4867-00
35 Seat Cage 1 L-7 9 9 5 - 0 0
36 Bushing O-ring 1D-4883-00
37 RV Module 1 W-9677-05
38 RV Cover 1Q-6965-05
39 RV Clamp 1W-9182-00
40 Screw, 5/16-18 x .50 1 B-1715-00
41 RV Washer 1E-2863-00
42 RV Seat Disc 1 D-4863-00
43 RV Stem 1G-4803-00
44 RV Stem O-ring 1 D-4744-00
45 RV Bushing 1 I-9271-15
46 RV Spring 1A-2500-00
47 Diaphragm Washer 1E-2864-00
48 Diaphragm 1D-4861-00
49 Diaphragm Plate 1E-2867-00
50 Dia. Plate O-ring 1 D-4865-00
51 Screw, 5/16-18 x .75 1 B-1751-00
52 Adapter w/ Extension 1K-4618-06
Individual parts are only available for bulk sales. Please refer to the appropriate repair kits on page 18.
PARTS LIST - 2-1/2” - 6”

18
Customer Service [phone] www.apolloflowcontrols.com
“Apl” Flow Controls
INSTALLATION, OPERATION & MAINTENANCE
MANUAL
REPAIR KITS (MAINLINE) 2-1/2” - 6”
CHECK RUBBER ONLY KIT
(ONE KIT REPAIRS ONE CHECK)
SIZE
2-1/2” & 3” 4” 6”
REPAIR KIT MODEL NUMBER RK4A3CMR RK4A4CMR RK4A6CMR
ITEM # ORDERING NUMBER 4A-000-01 4A-00A-01 4A-00C-01
not shown Lubricant I-9016-00
25 Disc D-4958-00 D-4862-00 D-4890-00
24 Check Seat O-ring D-5171-00 D-4869-00 D-5000-00
8 Relief Valve Port O-ring D-4866-00
16 Cover O-ring D-4976-00 D-4870-00 D-5001-00
15 Test Cock O-ring D-4892-00 D-3904-00
RP FIRST CHECK COMPLETE KIT
(ONE KIT REPAIRS ONE CHECK)
SIZE
2-1/2” & 3” 4” 6”
REPAIR KIT MODEL NUMBER RK4A3RPCMC RK4A4RPCMC RK4A6RPCMC
ITEM # ORDERING NUMBER 4A-000-03 4A-00A-03 4A-00C-03
not shown Lubricant I-9016-00
20 1st Check Module S-Assy W-9855-05 W-9666-05 W-9670-05
24 Check O-ring D-5171-00 D-4869-00 D-5000-00
16 Cover O-ring D-4976-00 D-4870-00 D-5001-00
RP SECOND CHECK COMPLETE KIT
(ONE KIT REPAIRS ONE CHECK)
SIZE
2-1/2” & 3” 4” 6”
REPAIR KIT MODEL NUMBER RK4A3DCRP2CMC RK4A4DCRP2CMC RK4A6DCRP2CMC
ITEM # ORDERING NUMBER 4A-000-14 4A-00A-14 4A-00C-14
not shown Lubricant I-9016-00
12 2nd Check Module S-Assy W-9857-05 W-9667-05 W-9671-05
24 Check O-ring D-5171-00 D-4869-00 D-5000-00
16 Cover O-ring D-4976-00 D-4870-00 D-5001-00
RP RELIEF VALVE RUBBER KIT
REPAIR KIT MODEL NUMBER RK4A6RVR
ITEM # ORDERING NUMBER 4A-00C-04
not shown Lubricant I-9016-00
34 RV Seat O-ring D-4867-00
36 Bushing O-ring D-4883-00
42 RV Seat Disc D-4863-00
44 Stem O-ring D-4744-00
48 Diaphragm D-4861-00
50 Diaphragm Plate O-ring D-4865-00
8 Relief Valve Port O-ring D-4866-00
RP RELIEF VALVE COMPLETE KIT
REPAIR KIT MODEL NUMBER RK4A6RVC
ITEM # ORDERING NUMBER 4A-00C-05
not shown Lubricant I-9016-00
34 RV Seat O-ring D-4867-00
35 Seat Cage L-7 9 9 5 - 0 0
36 Bushing O-ring D-4883-00
37 RV Module W-9677-05
8 Relief Valve Port O-ring D-4866-00
Note: All bronze components listed are lead-free*
*LEAD FREE: The wetted surfaces of this product shall contain no more than 0.25% lead by weighted average. Complies with CA
AB1953, VT Act 193, MD HB372, LA HB471, and Federal Public Law 111-380.
REPAIR KITS - 2-1/2” - 6”

19
Customer Service [phone]
backflow.apollovalves.com
ES1600 REV A.
BFMMRP4ALBF
REVERSE ANGLE
8" ONLY
1
2
3
4
5
6
7
8
9
10
11
12
13
14
17
16 15
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37 38
39 40
41
42
43
44
45
18
19
20
21 22 15
PART NUMBER DIAGRAM - 8” - 12”
RP4A, RPLF4A
RPDA4A, RPDALF4A (MAINLINE)
RPDA24A, RPDA2LF4A (MAINLINE)

20
Customer Service [phone] www.apolloflowcontrols.com
“Apl” Flow Controls
INSTALLATION, OPERATION & MAINTENANCE
MANUAL
RP4A / RPDA4A (MAINLINE) / RPDA24A (MAINLINE) PARTS LIST
RPLF4A / RPDALF4A (MAINLINE) / RPDA2LF4A (MAINLINE) PARTS LIST
ITEM # DESCRIPTION QTY. PART NUMBER
8” 10” 12”
1Shut-o Valve 2 See Page 26 & 27
2Nipple 2K-3412-00
3 Test Cock, FxF 2 77CLF-104-10
4Valve Body 2Consult Factory
5Screw 2B-2348-00 B-1690-00
6 Relief Valve Sub-Assy 1 W-9676-05 W-2329-05
7 O-ring, RV Port 1 D-4963-00 D-2304-00
8Plug, 1/2" NPT 1K-4594-05 N/A N/A
9Coupling 2W-9791-00 W-5242-00 N/A
Bolt Pack 2N/A N/A 40-00H-BP
10 Test Cock 177CLF-804-10 77CLF-104-10
11 Second Check Module 1W-9673-05 W-9862-05
12 Cover Clamp 1W-9243-00 W-9355-00
13 Cover 1E-2898-05 Q-7064-19
14 Test Cock, Cover 1 77CLF-804-10 77CLF-104-10
15 Locknut, 1/2-13 (QTY) C-2638-00 (24) C-2638-00 (32)
16 RP First Check Module 1 W-9674-05 W-9863-05
17 Check O-ring 1 D-4935-00 D-4997-00
18 Seat/Spring Sub-Assy 1W-9721-05 W-9723-05
19 Disc 1D-4934-00 D-4960-00
20 Disc Retainer 1F-3899-00 F-3903-00
21 Washer 2E-2897-00
22 Handle 2H-3828-00 H-3813-00
23 Adapter w/ Extension 1K-4618-00 N/A
24 Elbow, Street 1K-4600-00 N/A
25 Nipple 1K-3982-00 N/A
26 Sensing Hose 1W-9898-00 W-9898-00
27 Street Elbow 1K-4600-00
28 RV Body 1 Q-6992-05 Q-7102-05
29 RV Seat O-ring 1 D-4883-00 D-3506-00
30 RV Seat 1 L- 8 0 47 - 0 0 L- 8 1 69 - 0 0
31 Bushing O-ring 1D-2565-00 D-4858-00
32 RV Module 1 W-9675-05 W-2330-05
33 Diaphragm 1D-2564-00 D-2591-00
34 RV Cover 1Q-6994-05 Q-7103-05
35 Screw (QTY)B-1796-00 (8) B-1703-00 (8)
36 Nipple 1K-3460-00
37 Screw 1B-1753-00 B-1796-00
38 Washer 1E-2200-00 E-2210-00
39 RV Disc 1 D-2563-00 D-2595-00
40 RV Stem 1G-3240-00 G-4858-00
41 RV Stem O-ring 1 D-2562-00 D-2594-00
42 Bushing 1I-9269-15 I-9431-15
43 Spring 1A-1742-00 A-1749-00
44 Diaphragm Plate (QTY)E-2201-00 (1) E-2209-05 (2)
45 Screw 1N/A B-1800-00
Individual parts are only available for bulk sales. Please refer to the appropriate repair kits on page 21.
Note: All bronze components listed are lead-free*
*LEAD FREE: The wetted surfaces of this product shall contain no more than 0.25% lead by weighted average. Complies with CA
AB1953, VT Act 193, MD HB372, LA HB471, and Federal Public Law 111-380.
PARTS LIST - 8” - 12”