Kromschroder Gas pressure regulator GDJ20R04-4 03155037

The Kromschroder GDJ20R04-4 gas pressure regulator (SKU 03155037) is a spring-loaded reducer with inlet pressure compensation and zero shut-off. It maintains outlet pressure within 5–160 mbar despite inlet pressure fluctuations up to 400 mbar. The regulator has a nominal diameter of 20 mm with Rp 3/4" female thread, and operates in ambient temperatures from -20°C to +60°C. It features a built-in safety diaphragm without a vent line, and a turndown ratio of 10:1. Suitable for natural gas, LPG, and dry air.

When selecting a replacement gas pressure regulator of this type, ensure the connection size (e.g., Rp 3/4"), inlet pressure rating, outlet pressure range, and flow capacity match the burner output. Verify compatibility with the gas type and ambient temperature conditions. The regulator may have an integrated safety shut-off function or a vent line; check the existing installation's configuration. Outlet pressure is adjustable via a threaded screw, and a pressure gauge connection may be provided for commissioning.

Common failure modes include diaphragm rupture or debris blockage, leading to unstable outlet pressure or failure to maintain set point. Symptoms may include burner flame fluctuation, incomplete combustion, or inability to modulate. Check for inlet pressure variations, inspect the diaphragm for damage, and verify the outlet pressure setting against the burner requirements.