These units incorporate a small air sensing coil, and are used where the requirement is to mount the complete control within the area being monitored. Since the majority of commercial refrigeration applications involve cold rooms, ice and occasional defrosting, it is often recommended that air coil thermostats have splash proof enclosures to IP66. O52 range is therefore very popular in these applications. Ranco air coil thermostats are available with fixed or adjustable differentials (narrow differentials are popular on air coil thermostats, as opposed to pressure controls where wide differentials are popular to avoid short compressor cycles).