Armstrong GP-2000 is a high performance, externally piloted reducing valve for large capacity requirements. Typical use is on intermittent service, including applications such as heat exchangers, steam coils, rotating dryers, process equipment and heating systems. With a 20:1 rangeability and high Cv, the GP-2000 is reliable and accurate (+/-1% of pressure set point from 5% to 100% of flow) over a long, troublefree service life.

Hardened stainless steel working parts are renewable in-line. Single seated for dead-end service. Available with both NPT (1/2" - 2") and flanged connections in 1/2" - 6" sizes. ANSI Class IV Shutoff.

Specifications

Application	Inlet Pressure psig (bar)	Reduced Pressure psig (bar)	Spring Color	Maximum Temperature °F (°C)	Minimum Differential psig (bar)	Body Material	Main Valve/Seat	Pilot Valve/Seat	Diaphragm	Color
Steam	NPT 15-300 (1-20)	*1.5-3 (0.1-0.21)	Yellow	450 (232)	7 (0.48)	Ductile Iron ASTM A536	Stainless Steel AISI 420	Stainless Steel AISI 301	Stainless Steel	Dark Gray
	150 lb. Flanged 15-185 (1-13)	3-21 (0.21-1.4)	Yellow
	300 lb. Flanged 15-300 (1-20)	15-200 (1-13.8)	Green

INFO

*NOTE: When using this spring range, remove one (1) pilot diaphragm. Capacities are reduced by 1/2 of capacity chart when this spring is being used. Maximum pressure reduction 20:1. Minimum pressure reduction is 85% of inlet pressure.

Installation Instructions

WARNING

This bulletin should be used by experienced personnel as a guide to the installation and maintenance of the Armstrong GP-2000 Pressure Reducing Valve.

• Close the isolation valves and open the by-pass valve to blow-down inlet piping. After having blown the system down, close the by-pass valve.
• Make sure steam trap is operating properly.
• Loosen the lock nut and the adjusting screw located on the top of the Pressure Reducing Valve in order to set the adjusting spring free.

Model GP-2000:

• Completely open the inlet valve and partially open the outlet valve.
• Turn the adjusting screw clockwise until the desired pressure is reached at the outlet. Tighten the lock nut to block the adjustment.
• Completely open the outlet valve, pressure reducing station should now operate normally.
• To shut the system down, close the inlet valve first, then the outlet valve.

Model GP-2000R:

• Partially open the inlet valve and completely open the outlet valve.
• Make sure the inlet pressure is set at the value to be maintained. Turn the adjusting screw clockwise until the valve opens completely. Valve should close when inlet pressure decreases. Tighten the lock nut to block the adjustment.
• Completely open the inlet valve, pressure reducing station should now operate normally.
• To shut the system down, close the inlet valve first, then the outlet valve.

Typical Plumbing Diagram

Step 1: Isolate all PRVs using gate valves Step 2: Open gate valve to top PRV. Set outlet pressure. Step 3: Re-Isolate all PRVs using gate valves Step 4: Open gate valve to bottom PRV. Set outlet pressure. Step 5: Open all gate valves: Test and adjust as necessary.

GP-2000W1P Non Electric Self Controlled Shut Down Device

The Armstrong GP-2000W1P is a self-controlled shut down device avoiding the need for electricity to control systems, providing safe dependable shut down of the main steam valve when water pressure fails or drops rapidly on a fixed pressure steam water heater. The GP-2000W1P combination valve essentially lets the steam pressure modulate below the water pressure by 2 or 3 pounds, allowing a water heater to supply hot water even when water pressure is low.

Maintenance

TIP

Equipment under pressure - Operating temperature > 100°C. Make sure pressure reducing valve is cold before handling!

I. Pilot Valve Replacement:

• Loosen the lock nut and turn the adjusting screw counterclockwise until pressure is relieved from spring.
• Unscrew the bolts and take out the adjusting spring, the bottom plate and the 2 pilot diaphragms.
• Remove the pilot valve capsule and disassemble it. If necessary clean the internal parts or replace complete pilot valve capsule.

II. Main Valve Replacement:

• Disassemble the copper tubing on the side of the valve.
• Unscrew the 4 bolts linking the pilot body to the main body. If the pilot is mounted remotely, remove the cover from the top of the main body.
• Remove the spring retainer, the screen, the main spring and the main valve. Clean or replace main valve if necessary.
• Unscrew the 4 bolts between the main body and the top of the diaphragm case. Remove main valve seat and clean or replace it if necessary.

III. Main Diaphragm Replacement:

• Remove all bolts and nuts linking the top diaphragm case and the bottom diaphragm case.
• Remove the 2 main diaphragms, the retainer and the main spindle.
• Replace the diaphragms if they are damaged.