Web-Exclusive Sidebar: Industrial Process Chillers
July 1, 2008
Most modern chillers display a fault or error code when conditions affecting performance are detected. These codes are usually fairly specific and will help you quickly diagnose problems. Some of the more common alarms and faults are listed below.
Low-Temperature Alarm. The process temperature has fallen below a user-set temperature value, possibly due to an insufficient heat load or a low-temperature alarm setting that is too high.
High-Temperature Alarm. The process temperature has risen above a user-set temperature value, possibly due to an excessive heat load or a high-temperature alarm setting that is too low.
Over-Temperature Safety Alarm. The process temperature has exceeded a factory- or user-set safety cutoff, possibly due to a problem with the refrigeration system or a temperature safety setting that is too low.
Low-Liquid-Level Alarm. The level of coolant in the reservoir has fallen below an acceptable level, possibly due to evaporation or leaks in the circulation system.
Low-Flow Alarm. The fluid flow rate has dropped below a minimum factory- or user-set safety setting, possibly due to restrictions or blockages in the process lines or equipment, a failing pump, insufficient coolant, or a minimum flow rate setting that is set too high.
High-Pressure Alarm. The process pressure has risen above a factory- or user-set safety setting, possibly due to restrictions or blockages in the process lines or equipment. The installation of a pressure bypass valve can be helpful in applications with naturally high process fluid pressures.
High-Ambient-Temperature Alarm. The ambient temperature has risen above a factory- or user-set safety setting, usually due to changes in environmental conditions, such as a new location or the installation of other heat-generating equipment close to the chiller.
High-Discharge-Pressure Alarm. The refrigerant discharge pressure is too high, possibly due to a dirty or blocked condenser, dirty air filter, failing or failed cooling fan, high ambient temperature, or over-charging of the refrigerant system.
Low-Discharge-Pressure Alarm. The refrigerant discharge pressure is too low, possibly caused by refrigerant leakage, clogging of the condenser tubing, under-charging of the refrigerant system, or low ambient temperatures.