Refrigeration technicians are often called upon to service and repair reach-in coolers. The refrigeration systems used on these units are very similar among models from various manufacturers. Most of these coolers are self-contained with an air-cooled condensing unit, use capillary tubes as their metering device, and use a constant cut-in temperature control to maintain case temperature.
A common repair on these coolers is to replace the temperature control. Using the wrong type of temperature control can cause problems down the road.