Spirax Sarco DP27, Installation And Maintenance Instructions Manual

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IM-P470-03 CH Issue 7
22
5.5 How to clean or replace the internal strainer screen
DP27, DP27E and DP27Y
Isolate the reducing valve and zero the pressure.
DP27R
Isolate the actuating air supply and zero the pressure.
13 . Unscrew the unions and release the pipework.
14. Unscrew the nuts.
15. DP27, DP27E and DP27Y
Remove the pilot valve housing; complete with spring housing assembly.
DP27R
Remove the pilot valve housing, complete with air control block.
16. Remove the internal strainer screen and clean or replace.
17. Ensure the gasket faces are clean.
18.
Check that the main valve return spring is in position.
19. Fit a new gasket.
20. Replace the internal strainer screen.
21. DP27, DP27E and DP27Y
Assemble the pilot valve housing complete with spring housing assembly and tighten the
nuts to the recommended torques shown in Table 1, page 21.
DP27R
Assemble the pilot valve housing complete with air control block and tighten the nuts to
the recommended torques shown in Table 1, page 21.
22. Refit the pipework and retighten unions to ensure a tight seal.
Bring the valve back into commission, following as many steps as necessary in Section 4,
page 16.