1, why the O-ring sealed pressure sensor can't work with ammonia?
Ammonia offers refrigeration pump and compressor manufacturers an improved efficiency over Freon based systems. However, the thermodynamic behavior of ammonia is very different from Freon. When the refrigeration pump turns on, the ammonia temperature rapidly changes from 100°F to -70°F or below. This accelerated change, along with the type of sensor diaphragm material affects the pressure transducer performance and ultimately the control system. O-ring sealed pressure sensors cannot withstand rapid thermal changes and over time the internal O-ring will fail. Fluid filled pressure sensors suffer from freezing effects. This causes a rupture of the thin diaphragm membrane, which is welded in place to hold in the silicone oil-fill.
2, what kind of sensor can work with ammonia?
Pressure sensor designed with all stainless steel structure, no o-ring inside.
