Bunn CDS-2 and CDS-3 Error Codes
Flashing Lights In The Control Drawer
While the newer Bunn Ultra machines have a more sophisticated main control board and a digital display to assist in troubleshooting, the CDS machines also have a few troubleshooting tricks up their sleeves. In the center of the control drawer are two or three red light emitting diodes (LEDs), which can tell us a bit about the condition of your machine.
First to remember is that when the LED is on steady, the computer is telling the machine to deliver refrigerant to that hopper. If the LED is off, no refrigerant is being pumped to that hopper. If the lights are on steady and your compressor does not turn on, you should initially rule out the main control board and start troubleshooting the compressor circuit.
When you first turn on the machine and set it to freeze, the lights should flash a bit and then glow steady. If you see flashing after the first minute or two, the machine is actually sending an error code for that hopper. A code will be flashed with one, two, three or four flashes followed by a pause and then the cycle repeats.
Fault Code Meanings:
1 Flash – No motor rotation detected. This can mean: you have set the hopper to Ice but have not turned on the auger; the auger motor is not turning; the pins sticking up from the motor and/or auger shafts are missing or bent; or the torque sensor board or wiring is faulty. This hopper will not freeze.
2 Flashes – Thermistor Circuit Open. The thermistor is the temperature probe in each hopper that sends a signal to the main control board telling it the hopper temperature. The thermistor is either unplugged, the thermistor has failed, or the wiring is faulty. This hopper will have no Night mode or No Ice mode.
3 Flashes – Torque lower than possible. This means the torque sensor system has a problem (the system has measured the distance between the auger shaft and motor shaft pins and it is too small). Problems can be: the pins on the auger shaft or motor shaft are bent; there is excess grease or debris on the pins; or the torque sensor board or wiring is faulty. This hopper will not freeze.
4 Flashes – Torque higher than possible. This means the torque sensor system has a problem (the system is measuring the distance between the pins is too large). The pins on the auger shaft or motor shaft are bent; there is excess grease or debris on the pins; a pin is missing; or the torque sensor board or wiring is faulty. This hopper will not freeze.
If you have a CDS-2 or CDS-3 machine that does not freeze hopefully these codes and their meanings will help you diagnose and repair the problem.
Remember that you can also use your machine to keep beverages cold but not frozen by turning on the augers and setting the hopper to “No Ice” mode.
For more information or to contact us, go to: The Margarita Guys Store