TFP1326
Page 17 of 22
Step 6. Reset the electric detection 
system in accordance with the manu-
facturer’s instructions to de-energize 
the Solenoid Valve (N), and proceed 
as follows:
•  Water should cease draining from the 
Solenoid Valve (N).
•  Pressure will then build up in the 
DV-5A Diaphragm Chamber.
•  After system pressure is restored 
in the DV-5A  Diaphragm Chamber, 
inspect the Solenoid Valve (N) for 
leaks at the drain tube. Any leaks 
must be corrected before proceed-
ing to the next step. The Solenoid 
Valve (N) discharges water into the 
riser and must be drained at the con-
cluson of this test.
Step 7. Partially open the System 
Main Control Valve (B). Slowly close 
the Main Drain Valve (D) as soon as 
water discharges from the Main Drain 
Valve (D). Observe the Automatic Drain 
Valve (F) for leaks. If there are leaks, 
determine/correct the cause of the 
leakage problem. If there are no leaks, 
the DV-5A Valve is ready to be placed 
in service and the System Main Control 
Valve (B) must then be fully opened.
Internal Valve Inspection
Once every five years during the annual 
operational test procedure and prior 
to the DV-5a Valve being reset and 
with the DV-5a  Valve de-pressurized, 
the interior of the DV-5a  Valve must 
be cleaned and inspected for wear 
and damage. Damaged or worn parts 
must be replaced. (Replacement of the 
Diaphragm every ten years is recom-
mended, or more frequently if inspec-
tions and/or wear and tear warrant 
more frequent replacement.)
NOTICE
The Diaphragm Cover may be removed 
between Steps 4 and 5 of the reset-
ting instructions, since at that point the 
DV-5a Valve should be de-pressurized 
as evident by a zero gauge reading on 
the Diaphragm Gauge (K) and Water 
Supply Gauge (J), as well as no water 
discharging from the Automatic Drain 
Valve (F).
Ensure that the Diaphragm Supply 
Valve (P) and the System Main Control 
Valve (B) are closed before removing 
the cover.
To perform internal valve inspection 
between Steps 4 and 5 of the Valve 
Setting Procedure, remove the dia-
phragm cover as follows:
Step 1. Close the Inverted Flare Shut-
Off Valve (R).
Step 2. Remove the Copper Tube 
Fitting between the Diaphragm Supply 
Valve (P) and the Inverted Flare Shut-
Off Valve (R).
Step 3. Loosen the union securing the 
Solenoid Valve (N).
Step 4. Loosen and remove the union 
between the Diaphragm Cover and the 
trim and remove the trim.
Step 5. Remove the Diaphragm Valve 
Cover hardware, then slowly remove 
the Diaphragm Cover and perform 
internal valve inspection. Clean the 
valve interior and replace parts as 
necessary.
After cleaning and inspecting valve 
interior, and replacing parts as nec-
essary, reinstall the Diaphragm Cover 
by completing the following steps to 
assure the Diaphragm Cover Fasteners 
are uniformly and securely tightened.
Step 1. With reference to Figure 1, 
ensure that the Diaphragm is properly 
oriented and that the proper hardware 
arrangement is utilized when assem-
bling the Diaphragm Covers. The hard-
ware arrangements differ depending on 
the size of the DV-5a Valve.
Step 2. By first using the Long Hex 
Bolts, support of the Diaphragm Cover 
will be provided before installing the 
Short Hex Bolts. Align Diaphragm in 
proper orientation with Valve Body, and 
then align Diaphragm Cover in proper 
orientation with Valve Body. Hand-
tighten all fasteners.
Step 3. Using crossdraw sequence 
to assure uniformity, wrench-tighten 
Long Hex Bolts and Short Hex Bolts 
to appropriate torque values. Repeat 
crossdraw sequence two to three 
times at incremental torque valves 
until reaching the torque valves found 
in Table C.
Step 4. Inspect to assure all Hex Bolts 
are securely tightened.
Step 5. Using the union, the trim to the 
Diaphragm Cover.
Step 6. Using the union, secure the 
solenoid Valve (N).
Step 7. Replace the Copper Tube 
Fitting between the Diaphragm Supply 
Valve (P) and the Inverted Flare Shut-
Off Valve (R).
Step 8. Ensure that the unions and flare 
fittings are securely tightened.
Step 9. With the Diaphragm Supply 
Valve (P) closed, fully open the Inverted 
Flare Shut-Off Valve (R) stainless steel 
screw (approximately ½ in.) until resis-
tance is met so as not to break the 
internal roll-pin. The internal roll-pin 
stops the removal of the Inverted Flare 
Shut-Off Valve (R) stainless steel screw.
Step 10. Proceed to step 5 of the Valve 
Setting Procedures section in this data 
sheet.
NOTICE
If the water supply contains chemicals 
which tend to attack a polyester fabric-
reinforced, EPDM rubber or the five 
year inspection indicates a build-up of 
debris within the DV-5A Valve that could 
affect its proper operation, then the 
frequency of the internal valve inspec-
tion procedure must be appropriately 
increased.
With reference to Figure 1, make 
certain that the Diaphragm is correctly 
oriented; otherwise, the DV-5A Valve 
cannot be properly set.
Under-tightening the Diaphragm Cover 
Bolts can result in internal and external 
leakage.
Use only TYCO replacement fasteners 
as specified in Figure 1.
Do not apply adhesives, lubricants, or 
other substances to the Diaphragm or 
Valve Body.
Nominal 
Valve Sizes 
ANSI  
Inches
(DN)
Torque 
lb-ft 
(N∙m)
Nuts
Short  
Hex  
Bolts
3 
(80)
188 
(254,9)
150 
(203,4)
4 
(100)
396 
(536,9)
316 
(428,4)
6 
(150)
265 
(359,3)
212 
(287,4)
8 
(200)
545 
(738,9)
436 
(591,1)
TABLE C 
DIAPHRAGM COVER BOLTS 
MINIMUM TORQUE