Gm-4_5_ (Dual On/Off With Servo Precision Regulator) - Johnson Controls GM 20 Series Installation Sheets Manual

This valve provides controls for step/slow opening (for smooth ignition)
GM-_ _4_
and pressure regulation (for maintaining outlet gas pressure).
(Dual On/Off
Step-slow
Refer to the GM-_ _3_ version for setting the gas pressure at the valve
Opening with
outlet. For setting of the start gas position and maximum flow rate, see the
Pressure
GM-_ _2_ version.
Regulator)
This valve provides servo regulation for precision control of the valve
GM-4_5_
outlet pressure. To set the valve for the desired outlet pressure, the start
(Dual On/Off
gas pressure must be adjusted first.
with Servo
Precision
To set the start gas position, energize the solenoid coil to open the valve
Regulator)
seats. Remove the pressure tap plug (see Figure 9) located below the gas
outlet pipe connection and measure the start gas pressure. The adjustment
scale (P
therefore, a subsequent fine adjustment may be necessary. Use the
hexagonal tool provided (or an acceptable Allen wrench) to adjust the P
scale and obtain the desired start gas pressure.
G—GM-20/25 and GM-40/45 Series Dual-block Multi-function Gas Control Valves Technical Bulletin 13
All manuals and user guides at all-guides.com
) indicates the factory-set start gas pressure (see Figure 10);
ST
Figure 9: Valve Outlet Pipe Connection
P
Figure 10: P and P
ST
P ressure
Ta p P lug
6
2 10
P
G
5-50
ST
Adjustment Scales (Metric Shown)
G
ST