E3
Certikin
External Interlock / Safety Circuit Open
E3 error appears and heater stops; may be associated with tripping of external safety devices.
Advertisements
Safety Warning
This repair may involve working with high voltage components or water connections. Always unplug the appliance before removing any panels.
If you are not confident in your ability to perform this repair safely, we strongly recommend contacting a professional technician.
Advertisements
Possible Causes
Open circuit in external flow switch wired to Certikin heater, Tripped emergency stop or fireman’s switch, Faulty connection in remote thermostat or BMS interface, Broken link on safety interlock terminals
How to Fix / Troubleshooting
Safety first: Isolate power before working on control wiring. Do not bypass safety devices permanently.
- Identify interlocks: Refer to the wiring diagram on the Certikin heater to locate external safety and interlock terminals.
- Check emergency devices: Ensure any emergency stop buttons or fireman’s switches are reset and in the run position.
- Inspect wiring: Look for loose or broken wires on the external interlock terminals and junction boxes.
- Temporary test link (for diagnosis only): A qualified person may temporarily link the interlock terminals to confirm if the external circuit is at fault. Remove the link immediately after testing.
- Reset and test: Restore power and see if E3 clears.
Any faulty external safety devices must be repaired or replaced; never leave the heater operating with interlocks bypassed.
Advertisements
Repair Difficulty
Hard
4/5
Required Part
Certikin external safety interlock circuit
Check Price on Amazon
We may earn a commission from links on this page.
Advertisements