Curtis Coffee Maker Troubleshooting & Error Codes

/ Commercial Coffee Equipment, Troubleshooting / October 3

Curtis Coffee Maker Troubleshooting-Curtis Logo

Curtis Coffee Maker Troubleshooting Tips

Any cafe or commercial kitchen needs good coffee machines. Curtis manufacturers various coffee makers that can whip up a tasty brew in matter of minutes. If these machines stop working, business can come to a grinding halt. Fortunately, our guide has all the troubleshooting tips and error codes for Curtis Coffee makers, so your brewer can get back up and running quickly.

These tips and codes associated with popular models, including CGC, ThermoPro®, Airpot and CAFE series brewers.

Water Not Hot Enough



  • Incorrect temperature setting – Check the control panel to see if the temperature setting is too low. If so, you’ll need to reprogram.

  • Broken temperature sensor – If the temperature of the water doesn’t match the temperature displaying on the control panel, the temperature sensor is broken and will need to be replaced. On CAFE series Airpot and Thermal Decanter machines with a mechanical thermostat, the entire thermostat will need to be replaced by an authorized technician.


Water Won’t Heat at All



  • Water level not contacting probe – If the water in the tank doesn’t fill to the proper level, it won’t come in contact with the water probe. Please see the Water Tank Won’t Fill for more information.

  • Heating element or electrical issues – If you notice “Ready to brew,” “Ready” or “Heating” on the display but the water is still cool, there could be a variety of causes. The coffee maker could have an open heating element, bad wiring or other electrical issues. These should be checked and repaired by an authorized technician.


Water Heats Slowly

When the water heats slowly, there could be issues with a heating element. Contact an authorized technician to check power across the terminals of the element. If there is power to the element, the element will need to be replaced if the resistance is high. If there is no power to the element at all, wiring to one of the elements won’t have proper voltage across it. An authorized technician will need to check for corroded connections between the wiring and element.

Water is Too Hot

If the water is too hot to the point where it boils or steams excessively, check for the following:


  • Temperature too high for elevation – The control panel temperature on the machine should be adjusted to compensate for high elevation. Reduce the factory temperature setting (200°F) by two degrees for every 1,000 feet of elevation above 4,000 feet.

  • Faulty temperature sensor – If the display shows “Heating” constantly, the temperature sensor might need to be replaced by an authorized technician.

  • Faulty UPM or shorted triac – A faulty universal power module (UPM) or shorted triac can lead to extremely hot temperatures. These issues should be checked and repaired by an authorized technician.

  • “Over Temp Sensor” or “Ready to Brew” error – For more information on these errors, check the error codes section under Over Temper Sensor.


No Power/Display Won’t Light



  • Power switch is off – See if the main power toggle switch on the back panel is OFF.

  • Unplugged – Make sure the power cord is plugged into the electrical outlet.

  • Empty water tank – When the water tank is empty, it could trip the hi-limit switch. Refill the tank and push the hi-limit reset button.

  • Faulty hi-limit switch – If there is water in the tank but still no power, push the hi-limit reset button to restore power. If power isn’t restored, the hi-limit switch will need to be replaced. If power is restored, check that switch isn’t opening at normal water temperatures. If it is, it will need to be replaced by an authorized technician.

  • Wiring issues – The wiring from the power cord could be overheated or burned. This should be checked and repaired by an authorized technician.

  • Electrical issues – The machine could be experiencing other electrical problems associated with the control board or universal control module. These should be checked and repaired by an authorized technician.


Water Tank Won’t Fill



  • Water supply off or clogged – See if the water supply is turned on. If so, there could be a blockage in the supply line, water filter or inlet valve.

  • Electrical issues – The machine could be experiencing other electrical problems associated with the inlet valve terminals or universal control module. These should be checked and repaired by an authorized technician.


Water Tank Overfills



  • Broken water inlet valve – Turn the switch from ON to OFF. If water is flowing in both the on and off positions, the water inlet valve will need to be replaced by an authorized technician.

  • Electrical issues – The coffee maker could have problems with the water probe or universal control module. Either issue should be checked and repaired by an authorized technician.


Dispenser Won’t Fill to Normal Level



  • Sprayhead dirty or out of alignment – Clean the sprayhead if there is a buildup of lime or debris. If the sprayhead isn’t properly aligned or installed, adjust it accordingly.

  • Obstructions in tubing – See if there are any blockages in the tubing throughout the machine. Clean or have an authorized technician replace if necessary.

  • Clogged or broken valves – Check if there are any obstructions in the dump, bypass and dilution valves. Replace any of those valves if they’re broken.

  • Low water pressure or flow rate – Make sure the water supply line meets the minimum specifications for the water pressure or flow rate. Check the owner’s manual for proper specs.

  • Electrical issues – The coffee maker could have problems with the terminals or universal control module. Both issues should be checked and repaired by an authorized technician.


No Water or Tea Flows from Brewer



  • Water supply is off – Turn the water supply back on.

  • Water tank probe not level – If the water tank probe isn’t level with the water in the tank, check for the possible issues laid out in Water Tank Won’t Fill.

  • Faulty UCM and UPM – The machine’s universal control module or universal power module (UPM) could be broken. This issue should be checked and repaired by an authorized technician.


Dispenser Overflows



  • Product still in machine – The dispenser should be empty before the brewing cycle.

  • Missing or broken sprayhead – If the sprayhead is missing or broken, have an authorized technician replace it immediately.

  • Incorrect brew volume – Make sure the brew volume is at the correct setting. Check the “Program Guide” in the owner’s manual for proper volume settings.

  • Open valve – If water still flows from the sprayhead, bypass outlet spout and dilution spout when the machine is turned off, one of the machine’s valves is open. Have it replaced by an authorized technician.

  • Faulty UCM and UPM – The machine’s universal control module or universal power module (UPM) could be broken. This issue should be checked and repaired by an authorized technician.


Curtis Coffee Maker Error Codes

Select Curtis machine displays error messages. Below is a quick guide for interpreting some common codes.

Water Level Error



  • What the issue? – Fill run error or overflow.

  • Possible cause – The water inlet valve could be open for more than 10 minutes on the initial tank fill. It also could be open for about 120 seconds on larger brewers or 30 second on CGC or tea brewers in normal operation.


Sensor Error/Temperature Sensor Error



  • What the issue? – Open probe.

  • Possible cause – The open probe is likely caused by a break in the temperature thermistor circuit.


Over Temp. Error



  • What the issue? – Excess temperature.

  • Possible cause – The senor has shorted to ground, or it’s reading that the temperature in the heating tank is above 210°


Communication Error (Airpot Brewing System Only)



  • What the issue? – Poor system communication.

  • Possible cause – When this occurs, there is typically a break in the communication wiring between the control boards and SPS module.


Maintenance Required (CGC Series Only)



  • What the issue? – Maintenance is needed.

  • Possible cause – This error message displays if the brew count “Gallons Since Reset” exceeds the programmed preventative maintenance cycle.


Low Water Flow Warning (CGC Series Only)



  • What the issue? – Water flow is very low.

  • Possible cause – The inlet valve remains on longer than proper time and repeats twice during the brewing cycle.


Internal Error 1 (CGC Series Only)



  • What the issue? – Poor communication between the universal power and control modules.

  • Possible cause – There is a break in the communication circuit for the universal power module and universal control module.


Internal Error 2 (CGC Series Only)



  • What the issue? – Mismatched settings in the universal power and control modules.

  • Possible cause – There is a settings mismatch in the universal power and control modules. This requires a firmware update.


Configuration Error (CGC Series Only)



  • What the issue? – Incompatible UPM software update.

  • Possible cause – The latest software update for the Universal power module isn’t supported by the brewer model.

Looking for more troubleshooting tips and error codes? Our collection of Curtis manuals have all the information you need.

Please contact a local authorized service agent who can help with these specific units and all your commercial kitchen equipment needs.


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