Error Code
medium
Hobart AM16 – Not Dispensing Chemicals
On your HOBART AM16 DISHWASHERS unit, chemicals not dispensing typically indicates issues…
Hobart AM16 - Error 004: Booster Temperature Not Reached During Wash Cycle
Critical / Stop Operation
Warning: The information provided here is for educational purposes only.
Working with commercial kitchen equipment involves high voltage, gas, and high temperatures.
We strongly recommend contacting a certified service technician for any repairs.
We are not responsible for any damage or injuries resulting from DIY repair attempts.
This information is provided 'as is' without any guarantees of completeness or accuracy.
TLDR
On your AM16 DISHWASHERS unit, error code 004 indicates the booster heater failed to achieve the target rinse temperature within the allotted time. This often points to issues with the booster heater element, its contactor, or temperature sensors. Inspect these components for continuity and proper operation to restore sanitization.
Technical Details
Repair Steps:
- Verify Power Supply and Circuit Breaker: Check the dedicated circuit breaker for the dishwasher’s booster heater. Ensure it hasn’t tripped. If it has, reset it. Also, check the main power supply to the unit for proper voltage.
- Inspect the Booster Heater Element: Disconnect power to the machine. Access the booster heater. Use a multimeter to check the continuity of the heating element. A lack of continuity indicates a failed element that requires replacement. Check for any visible signs of damage or calcification.
- Test the Booster Thermostat/High-Limit Switch: The booster likely has an operating thermostat and a high-limit safety thermostat. With power disconnected, check for continuity across both thermostats. If either is open when it should be closed (especially the high-limit after a cool-down), it may be faulty or have tripped due to an issue. Reset any manual reset high-limit if present.
- Examine the Booster Heater Contactor/Relay: This electrical switch supplies power to the heater element. With power on (and extreme caution), check if the contactor is pulling in when the booster should be heating. If it’s not engaging, check the coil voltage. If the coil is energized but the contacts don’t close, the contactor is likely faulty and needs replacement.
- Check Water Level and Flow: Ensure the dishwasher is filling to the correct level and that there are no obstructions in the rinse water supply line to the booster. Low water levels or restricted flow can prevent the heater from activating or reaching temperature.
- Evaluate the Booster Temperature Sensor: The AM16 uses a temperature sensor (e.g., RTD or thermistor) to monitor booster temperature. Disconnect power and check its resistance value. Compare it to the manufacturer’s specifications for various temperatures. A faulty sensor can provide incorrect readings, preventing the control from activating the heater or reporting an inaccurate temperature.
- Review Control Board Connections: Though less common, a loose connection or a fault on the main control board could prevent the booster from operating correctly. Visually inspect all wiring harnesses connected to the booster circuit on the control board for security and signs of burning.
Common Questions:
Q: Why is the booster temperature critical for commercial dishwashers?
A: The booster temperature is crucial for proper sanitization. Commercial dishwashers rely on high-temperature rinse water (typically 180°F / 82°C) to kill bacteria and pathogens, ensuring dishes meet health code standards. Without this, dishes are not safely sanitized.
Q: Can I continue using my HOBART AM16 DISHWASHERS if it’s showing error 004?
A: While the machine may complete a wash cycle, it is not recommended for commercial use. The dishes will not be properly sanitized, which poses a significant health risk and violates food safety regulations. Repair the booster heating system immediately.
Q: How can I prevent booster heater issues like error 004?
A: Regular preventative maintenance is key. This includes periodic descaling of the booster tank and heating element to remove mineral buildup, ensuring proper water quality (e.g., water softener if needed), and routine inspection of electrical connections and components like contactors and thermostats.
When to call a technician
For this error, we recommend calling a certified technician. Do not continue operation or attempt repair yourself.
- Equipment shows a critical or stop-operation fault.
- You smell gas, burning, or see smoke or sparks.
- Error returns after following the steps above.
- You are not trained to work on this equipment.
- Warranty or safety could be affected by DIY repair.