FEBCO 856ST MasterSeries In-Line Design Double Check Detector Assemblies - Manual (Page 4)

4
Servicing Check Valve Assemblies
General
FEBCO recommends yearly maintenance. Consult your local codes for requirements in
your area.
1. Detailed maintenance manuals
are available from your local Febco
representative.
2. Rinse all parts with clean water prior to
reassembly.
3. DO NOT USE ANY PIPE DOPE, OIL,
GREASE OR SOLVENT ON ANY PARTS
unless instructed to do so.
4. Do not force parts. Parts should fit
together freely. Excess force may
cause damage and render the assembly
inoperable.
5. Carefully inspect seals and seating
surfaces for debris or damage.
6. After servicing, repressurize the
assembly and test to ensure proper
operation.
Troubleshooting for Double Check Assemblies
PROBLEM CAUSE SOLUTION
1. Check valve leaking a. Debris on seating surface Disassemble and clean
b. Leaking shutoff valve. Disassemble and clean
2. Low flows passing through a. Mainline check fouled Disassemble and clean
b. Bypass line plugged Disassemble and clean
Disassembling the Check Valve
1. Close the outlet shutoff valve, then
close the inlet shutoff valve. Bleed
residual pressure from the assembly by
opening the #4, #3, and # 2 test cocks
in this sequence.
2. Remove the cover bolts/nuts and lift
the cover from the body. The springs
are retained and the cover should be
pushed away from the body approxi-
mately 1 ⁄
4
inch.
3. Inspect/clean debris from the disc and
seat ring. Replace worn or damaged
parts as required.
4. Replace the cover, ensure the spring
assembly is positioned in the pivot sock-
et. If necessary, apply FDA approved
grease to the O-ring groove in the body
to keep the O-ring in position while
installing the cover.
5. Install the bolts and nuts and tighten.
Test Procedure
FEBCO recommends the use of
the appropriate annual test method
presented in the ASSE Series 5000
manual that is consistent with your
local codes.