As the first component to activate during a heat call

often due to a clogged port

Why does the kit include multiple types of washers

What are the physical dimensions of the shaft

McDonnell & Miller 194-A Controller R-22 As the first component toThe McDonnell & Miller 194 A is a heavy duty combination low water cut off and pump controller designed specifically for commercial and industrial steam boiler applications. Engineered for systems with a maximum steam pressure of 250 PSI, this unit features dual snap acting SPDT switches to ensure precise boiler water level control and reliable low water protection. The 194 A series is often selected by technicians for high pressure environments where