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4X”- 6” Deringer 20/30 Maintenance Instructions
BD-INST-02030 | Rev C | 12/22/2015 | Copyright 2011 Backflow Direct, LLC
Installing Access Port Cover
1. It is best to never remove the Access Port O-ring (A). Should the Access
Port O-ring (A) become dislodged, simply insert it back into Access Port
Groove (B).
2. Slide the Access Port Cover (C) into place being certain that Access Port O-
ring (A) does not become dislodged during the process.
3. Insert Cover Bolts (D) and Tapered Washers (E) into Tapered Cover Holes
(F). Tapered Washers (E) must be properly installed or the Access Port
Cover (C) will not seal under pressure.
4. Use 15/16
” Socket Wrench (G) to tighten the 4 center Cover Bolts (D)
alternating from one side of the valve to the other. Then Tighten the four
corner bolts alternating from one side of the valve to the other.
A
BD-INST-4X2030 | Rev A | 09/06/2019 | Copyright 2011 Backflow Direct, LLC
Page 17 of 20
C
E
D
G
F
B