I bought my pressure relief valve from McMaster Carr for my Gast 0523. It is adjustable from zero to 20 psi. It always leaks a small amount, but is good insurance. IIRC I set it at 10psi - thereabouts. This is well enough above where my system operates. I had one of my three lines clog once and the new operating pressure was still lower than my pressure relief setting.

McMasterCarr part # 48935K25 - Adjustable Pressure- and Vacuum-Relief Valves for Air and Inert Gas, 440C Stainless Steel Seal, 1/4 NPT Male

The Gast 0523 wants to operate below 10psi for better life. It stalls out and sounds horrible at 20 psi (don't ask how I know).


Fish on!,
Noel