use a silicone-based lubricant on the cartridge O-rings during installation to ensure a proper seal

ensuring a seamless fit for technicians performing field retrofits or repairs

a mechanical internal failure is likely

this specific part is calibrated for natural gas applications

AERCO Boiler and Water Heater 18557-1 Tstat 321702-401 use a silicone-based lubricant onThe AERCO 18557 1 Pneumatic Bulb Thermostat is a critical OEM replacement part designed specifically for AERCO boiler and water heater systems. This RA 20 240 thermostat utilizes advanced pneumatic sensing technology to ensure the precise temperature regulation required for commercial heating environments. By providing dependable sensing through its bulb style design, the 18557 1 Tstat maintains peak efficiency and prevents the energy waste associated