Troubleshooting No Hot Water and Error Code 111

Enhancing your home's comfort starts with ensuring your water heating system functions flawlessly.

Among the myriad of issues that can plague tankless water heaters, the John Wood brand is no stranger to operational hiccups, particularly those resulting in no hot water.

A common culprit behind this inconvenience is error code 111, a puzzling signal that can leave users cold and frustrated.

This comprehensive guide explores troubleshooting and resolving error code 111, offering valuable insights for both homeowners and technicians to restore their water heater's functionality effectively.

Understanding error code 111

Error code 111 on a John Wood tankless water heater typically indicates a problem related to the unit's ignition or flame. This could be due to several factors, such as a failure in the ignition process, a faulty flame sensor, gas supply issues, or even an electrical fault.

Understanding the root cause of this error is crucial for effectively addressing the issue. It is not just a simple error but a signal pointing towards a range of potential problems affecting the heater's operation.

This error is displayed on the control panel or temperature controller. The unit attempts to ignite the gas burner three times; if unsuccessful, it shuts down.

Below is the procedure to fix the water heater, clear the error code, and resume heating operations.

Step-by-step guide to fixing error code 111

Check the hi-limit switch. The hi-limit switch prevents overheating by shutting off the heater if the water temperature exceeds a safe limit.

First, turn off the power to the water heater.

Press the white button on the hi-limit switch until you hear a click, indicating it has reset.

Turn the power back on and attempt to ignite the heater.

If the heater lights successfully, examine what might have caused the hi-limit switch to trip.

Ensure proper gas supply and line check. Verify that the gas is supplied at the correct pressure and that the gas line is free from debris and air. Inconsistent or inadequate gas supply can lead to ignition problems.

Inspect the Overheat Cutoff Fuse (OHCF). Locate the OHCF, which is typically white and wrapped around the heat exchanger. Disconnect the white clip at the end and use an ohm meter to check for continuity. If there's no continuity, it's time to call a professional, as the OHCF might require replacement.

Clean the flame sensor. If the flame ignites but extinguishes after 1-2 seconds, the flame sensor may need cleaning. Use 100-grit sandpaper to clean the flame rod to a bright finish, being careful to keep its position unchanged.

Examine the ignitor. Check the ignitor through the sight glass for a strong blue spark. A weak or erratic spark suggests an issue. Inspect the ignition wires for looseness or damage.

Check for vent blockages. Inspect the venting system for any obstructions like dirt or bird nests. A clear vent path is essential for proper heater operation.

Preventive measures and regular maintenance

To mitigate the risk of encountering error code 111 and other issues, regular maintenance of your John Wood tankless water heater is essential.

This includes periodic checks of the gas line, cleaning or replacing the filter, ensuring proper ventilation, and monitoring for any error codes or signs of wear and tear.

Preventive maintenance not only prolongs the life of the heater but also ensures its efficient and safe operation.