Carrier HH18HA120 Temp Switch 319825-402 The Watts 0342692 (Model M335M2)

The Watts 0342692 (Model M335M2) is a heavy-duty 3/4" boiler pressure relief valve engineered for hydronic heating systems and low-pressure steam applications

a "failed to prove" error on the integrated control board

this OEM part is engineered to detect abnormal high-temperature conditions—specifically flame rollout—and immediately break the electrical circuit to shut down the gas valve

Robust Sensing: The 8' capillary length and large sensing bulb provide highly accurate liquid or air temperature readings even in high-vibration environments

Carrier HH18HA120 Temp Switch 319825-402 The Watts 0342692 (Model M335M2)The Carrier HH18HA120 Temp Switch is a critical safety component designed for precise thermal regulation within residential and light commercial HVAC systems. Engineer specified with an operating temperature range of 120 30F, this OEM Carrier replacement part functions as a high limit safety or operating control to prevent equipment damage during abnormal thermal conditions. Built for durability in high cycle environments, it provides reliable HVAC