Rivacold HI

What does Rivacold HI mean?

Rivacold monoblocks and condensing units ship with a Carel, Eliwell, or Dixell controller, and HI is that controller's high-temperature alarm. On the Carel controllers it is signalled by the buzzer and the code HI on the display when the temperature exceeds the high-temperature alarm threshold (AH) for longer than the alarm delay (Ad), and it resets automatically once the temperature falls back by the reset differential (A0). It is a warning that the box is too warm.

Symptoms

• Display shows HI (or a flashing high-temperature alarm) with the buzzer/relay active
• Cabinet temperature reading sits above the setpoint band
• Alarm clears automatically once the temperature falls back below the threshold minus the differential

Common causes

• Recent door openings, a large warm load, or a failed door heater/seal letting heat in
• Condenser fouling, a failed condenser fan, or restricted airflow reducing capacity
• Refrigerant undercharge or a system fault preventing pull-down
• Defrost running long or terminating late, or the alarm threshold/delay set too tight

Diagnostic steps

1. 01

   Confirm it is a real over-temperature

   Read the actual cabinet probe temperature on the controller. If it is genuinely above setpoint, work the refrigeration cause; if the box is cold, suspect the probe or the alarm parameters.

2. 02

   Rule out the easy causes

   Check for a propped/leaking door, a recent load, and that defrost has finished. Let the unit attempt pull-down and watch whether the alarm clears on its own.

3. 03

   Check condenser and airflow

   Clean a fouled condenser, confirm the condenser fan runs, and clear any airflow restriction — the most common cause of a unit that cannot hold temperature.

4. 04

   Verify the alarm parameters

   Confirm the high-alarm threshold and delay match the application before chasing a fault — a threshold set too close to setpoint will nuisance-trip HI.

When to call a professional

If the condenser, fans, doors, and defrost are all good and the box still will not hold temperature, the unit likely has a refrigeration fault (undercharge, leak, restricted metering, or compressor capacity loss) — have a refrigeration technician check the charge and the system.