COLD/AMBIENT AIR THERMOSTATS: 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).
STRAIGHT AND COILED CAPILLARY THERMOSTATS: These controls are used on applications where it can be guaranteed that the sensing element is always colder than the control head. The sensing element used senses along the complete length. Where local sensing is required the coiled end version is used, whereas the straight version is used to sense over longer distance, e.g. across an evaporator coil. The only difference between the straight and coiled capillary thermostats is the coiling of the last few centimetres of sensing element. Available in standard (IP44), or splash proof (IP66) housing, and with adjustable differentials. Models with built-in 'stop' switches can be selected where a shut-down of the system from the
thermostat location is required, without altering the setting.
CROSS AMBIENT THERMOSTATS: These thermostats have a capillary and remote bulb. Unlike the straight or coiled capillary modules, these controls sense only at the bulb. They should be used on all applications where it is possible that the control head or capillary can be at a lower temperature than the sensing bulb, e.g. external applications where the bulb senses a defrosting coil. Ranco cross ambient thermostats fall into two categories/ narrow range, narrow differential and wide range, wide differential. Please note that these have different bulb sizes. Special ranges, differentials and bulb sizes can be made, subject to normal