What E3 Means
E3 on the RF24D refrigerated drawers points to the evaporator thermistor, which the DCS service manual calls “sensor B”. The reading is out of range, meaning the wire or sensor is open or shorted. That sensor tells the control when the cooling plate needs to defrost, so the drawers may frost up or run long cycles while E3 is showing.
Common Causes of E3
- Evaporator thermistor wire disconnected, leaving the circuit open
- Thermistor leads chafed and shorted together
- Thermistor failed after moisture got into its sleeve
🔧 One Safe Check You Can Try
Mute the alarm with any key, then open each drawer and look for heavy frost on the back wall or water pooled under the drawer liners. Keep the drawers closed as much as possible and check food temperature with a thermometer. The code clears only with a power cycle, and if it comes back the sensor needs testing.
⚠ Why You Shouldn't Go Further Than That
- The evaporator sensor is clipped behind the drawer liner near the cooling plate, and reaching it means removing the drawers and interior panels without cracking the liner.
- A good sensor reads a specific resistance at a known temperature, and replacing it without measuring often leaves a wiring break in place.
Opening a panel to inspect or repair something yourself doesn't automatically cancel your manufacturer's warranty — but it can risk accidental damage, and some manufacturers do have specific service conditions. Check your product's warranty terms, or ask us, before deciding.