With a fixed 20 degree F differential

Always check your nameplate data before installation to ensure the action type matches your system requirements

and LP-air mixtures without specialized conversion kits

It will close the circuit once the plenum temperature drops below the 120°F threshold

McDonnell & Miller 194 Controller Els PW 17895 With a fixed 20 degreeAs a veteran HVACR technician, you know that maintaining precise water levels in high pressure systems isn't just about efficiencyit is about safety and equipment longevity. The McDonnell & Miller 194 Low Water Cut Off and Pump Controller (Part Number 166600) is the industry standard for commercial and industrial steam boilers, engineered to operate reliably in environments up to 250 PSI max pressure. This heavy duty combination LWCO and pump