What is the difference between a normally closed and normally open solenoid valve

The /U indicates "universal" or retail packaging

including high ambient temperatures

As a veteran-grade HVAC condensate drain hose

OEM Compatibility: Identified as an exact drop-in for Heil Quaker 1175187 and 36H54-470

Lennox 10U66 Pressure Switch 322838-752 What is the difference betweenThe Lennox 10U66 Pressure Switch is a critical safety component designed for heavy duty HVACR applications, specifically engineered to monitor high side refrigerant pressures. This 670# M R Hi Pressure Switch acts as a fail safe mechanism, protecting the compressor and system piping from catastrophic failure caused by extreme pressure spikes. It features a specific actuation point of 640 PSI and is built with a manual reset (M R) configuration,