Blakeslee Conveyor Dishwasher Error Code C3: Pre-Rinse Heating Failure
C3 PRE-RINSE HEATING FAILURE means the pre-rinse section is not heating. The manual says to turn the machine off and on after a few seconds. If the alarm persists, call a service technician to check the heating circuit.
High: the pre-rinse cannot heat, so the machine cannot run to standard.
- Code
- C3
- Maker
- Blakeslee
- Equipment
- Conveyor dish machines
- Applies to
- Blakeslee rack conveyor with pre-rinse section (PDF is Blakeslee's 'RC64 User Manual'; the RC86 user manual is the same document); prints no model name
What does Blakeslee error code C3 mean?
After the pre-rinse tank is filled, the control switches its heater on and watches for the temperature to climb. If the section does not warm as expected, the control raises C3 PRE-RINSE HEATING FAILURE. The manual describes it as the pre-rinse section not heating, and the operator step is a reset: turn the machine off with the ON/OFF button, wait a few seconds and turn it back on. A reset can clear an alarm caused by a brief supply dip. If C3 comes back, the manual sends the operator to Technical Service, because the cause lies in the element, its relay, a safety device or the electrical supply, none of which an operator can safely test. C3 is about heat that does not arrive, while C5 is about too much heat.
Affected models and control systems
Blakeslee rack conveyor dishwasher with a pre-rinse section. The PDF is Blakeslee's RC64 User Manual, and the RC86 manual is the same document; it prints no model name.
Code numbers and their meaning can change between control generations. We match the full model and control before acting on a code.
What you may notice
- C3 PRE-RINSE HEATING FAILURE on the display
- First station water stays cool
- Soil not loosening in the pre-rinse
- Alarm returns after the ON/OFF reset
Possible causes
Likely causes — what usually sits behind error code C3 on this control. A technician confirms which one it is before any part is replaced.
- Pre-rinse heating element burned out
- Heater relay or contactor not closing
- Safety thermostat on the heater open
- Missing phase at the machine supply
Safe checks before calling for service
- Turn the machine off with ON/OFF, wait a few seconds, and turn it on again, as the manual says.
- Check that the breaker and disconnect for the machine are on.
- If C3 returns, stop running racks.
- Do not open panels or reach into the tank.
- Write down how many resets you made and when the alarm came back.
How a technician diagnoses error code C3
- Read the alarm history and look for a probe alarm near C3.
- Measure voltage on every phase at the machine while heat is called.
- Check the element for continuity and leakage to ground with power locked out.
- Test the relay or contactor and the safety thermostat.
- Confirm the probe reads correctly, then replace the failed part.
- Heating circuits draw high current at 208 to 240 volts or more.
- Relay and element tests are made inside live panels.
- The tank holds hot water above the wiring.
How error code C3 differs from similar codes
C3 is the pre-rinse not heating. B3 is the same for boiler 1, and E3 for wash tank 1.
Technical reference
- Document
- Instructions for Use and Maintenance (USA) rack conveyor with pre-rinse section; published on blakesleeinc.com as 'RC64 User Manual'
- Maker documentation
- Blakeslee owner support
- Edition
- COD. 4900E_U_USA, Ed. 01 - 02/2018
- Models / control
- Blakeslee rack conveyor with pre-rinse section (PDF is Blakeslee's 'RC64 User Manual'; the RC86 user manual is the same document); prints no model name
- Section
- Chapter 12.2.1 Alarms description (pp. 54-55)
- Checked
- October 2026
We use the maker's document to read the code and do not reproduce it. Always confirm the complete model and control before applying these steps.
Related Blakeslee conveyor dish machine error codes
Will an ON/OFF reset fix C3?
Sometimes, if the cause was a brief supply dip. If it returns, call.
How long before turning it on again?
The manual says a few seconds.
Does C3 mean the probe is bad?
No. That is C2.
Need help with Blakeslee error code C3?
A technician confirms the cause on site and gives you the price in writing before any work starts.