Kromschroder Air/gas ratio control GIK40R02-5 03155146

The Kromschroder GIK40R02-5 is an air/gas ratio control with a nominal diameter of 40 mm and Rp 1½" internal thread connection. It maintains a 1:1 gas/air ratio, with a maximum inlet pressure of 200 mbar and a pressure range of 0.005–1.2 mbar. This device features inlet pressure compensation, a compensation diaphragm, zero shut-off, and an outlet pressure test point. It is certified to EN 88 and CE/EU standards, suitable for natural gas and LPG applications.

When selecting a replacement air/gas ratio control of this type, verify the connection size and thread type (e.g., Rp 1½" internal thread) to match the existing piping. Ensure the maximum inlet pressure and pressure range cover the system's operating conditions. Check the gas/air ratio and turndown requirements, and confirm compatibility with the burner control system and gas type. The control may be installed with sensing lines connected to the air fan and gas valve; ensure proper orientation and sealing.

Common failures include diaphragm fatigue, spring drift, or blockage of the sensing line, leading to unstable gas/air ratio or incorrect pressure settings. Symptoms may include burner pulsation, incomplete combustion, increased CO or NOx emissions, or inability to maintain modulation. Check the sensing lines for blockages, inspect the diaphragm for tears or deformation, and verify spring adjustment against the required pressure range.