The presence of temperature and pressure sensors in the case control provides visibility into complete refrigeration system data for diagnostics and troubleshooting. When combined with a supervisory control system, case control enables remote transmission of an abundance of information, giving operators eyes into the system to help optimize maintenance activities, including:

  • Remote set point adjustment can eliminate the need for a service call
  • Technicians can see real-time information about system conditions before they’re dispatched
  • EEV’s automatic control of superheat makes the need for seasonal adjustments obsolete
  • Allows the most expert technicians to have access to remote diagnostics and direct field activities at multiple sites from a central office, thereby combating a declining knowledge base in skilled technicians (see Figure 2)
  • Increased Potential for Ongoing Energy Savings
    The precision with which case control and EEV systems deliver persistent system optimization provide ongoing energy-saving opportunities. In the evaporator, the EEV provides accurate control and eliminates parasitic losses found in mechanical thermal expansion (TX) valve systems. The EEV also ensures peak system efficiency at all times.

    One huge savings opportunity that can only be accomplished through case control with EEV systems is the ability to operate the refrigeration system at lower condensing pressures. Low condensing operation allows the head pressure to float with the ambient temperature and take advantage of lower temperatures that occur at night and in cooler seasons. Compared to conventional fixed head pressure operation, low condensing dramatically reduces mechanical stress on the system compressor and saves on energy costs:

  • Lower energy consumption — 15%–20% energy efficiency ratio (EER) per 10 °F drop in head pressure
  • Increased compressor capacity at lower condensing pressures
  • Maintenance cost reduction due to less mechanical stress

Case control generates additional cost savings via precise control over the following functions:

  • Localized, anti-sweat heater that response to case conditions
  • Case lighting as determined by occupancy schedule
  • Accurate defrost termination that shortens defrost cycles