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4X”- 6” Deringer 20/30 Maintenance Instructions
WARNING:
The First Check Module must be fully
seated to ensure Retainer Screws do not bind
against Check Towers. Binding Retainer Screws
against Check Towers will result in permanent
damage to First Check Modules.
1. Insert First Check Module (A) into Access Port
(B) with First Check Towers (C) pointing
downstream. Push First Check Module (A)
upstream into Valve Sealing Ring (D) until
Check O-ring (E) is resting against Valve
Sealing Ring (D). Coax First Check Module (A)
into its fully seated position by hand.
2. Alternatively, using a piece of 1
”x4” wood cut to
16
” length (F) as a lever between the Second
Check Seat (G) and the First Check Towers
(C), coax the First Check Module (A) into its
fully seated position.
3. Be certain First Check Module (A) is fully
seated and Check O-ring (E) is NOT
“fish
mouthed” or damaged.
4. Now fully tighten the First and Second Check
Retaining Screws (I) .
BD-INST-02030 | Rev C | 12/22/2015 | Copyright 2011 Backflow Direct, LLC
Installing First Dual-Action Check Module
Not Binding
Binding
BD-INST-4X2030 | Rev A | 09/06/2019 | Copyright 2011 Backflow Direct, LLC
Page 16 of 20
I
A
B
C
D
E
G
F
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