4
MR98 Series AD2000 Compliant
D-A-CH Region Only
Startup
The relief valve or backpressure regulator is factory
set at approximately the midpoint of the spring range
or the pressure requested, so an initial adjustment
may be required to give the desired results. With
proper installation completed and relief valves properly
adjusted, slowly open the upstream and downstream
shutoff valves (if applicable).
Adjustment
To change the control pressure, remove closing
cap or loosen the jam nut and turn the adjusting
screw clockwise to increase control pressure or
counterclockwise to decrease pressure. Monitor
the control pressure with a test gauge during the
adjustment. Replace closing cap or tighten the jam nut
to maintain the desired setting.
Taking Out of Service (Shutdown)
▲
WARNING
To avoid personal injury resulting from
sudden release of pressure, isolate
the regulator from all pressure before
attempting disassembly.
Parts List
Key Description
1 Body
2
Spring Case
3*
Orifice
4*
Valve Plug
5
Bottom Plug
7
Valve Plug Guide
8
Lower Spring Seat
9
Upper Spring Seat
10
Pusher Post
11
Control Spring
12*
Diaphragm (2 required for metal, Fluorocarbon (FKM) and
Ethylenepropylene (EPDM) diaphragms)
13 Nameplate
14
Diaphragm Protector (not shown)
15
Adjusting Screw
16
Cap Screws
Types MR98H, MR98HH:
DN 15 to 50 / 1/2 to 2 in. bodies - 8 required
17
Jam Nut
18
Drive Screw (4 required)
19*
Diaphragm Gasket (2 required for pressure loaded spring case)
24
Machine Screw
25
O-ring Retainer
25
Seat Retainer
28 Lockwasher
29* Gasket
31 Locknut
45* O-ring
47
NACE Tag (not shown)
48
Tag Wire (not shown)
52 Plug
53*
Valve Plug O-ring
57
Jam Nut (not shown)
58 Washer
59* O-ring
59* L-ring
62
Adaptor (not shown)
63*
Bottom Plug Seal
64
Flow Arrow
65
Pipe Plug (not shown)
66
Pressure Gauge (not shown)
68
Restriction (not shown)
69
ATEX Tag (not shown)
70
PED Tag (not shown)
*Recommended spare part
