Suburban st-42

[Trey1969]

I replaced my Suburban st42 water heater with a identical model. But now I'm getting error code EC. Anybody know what it could be?

 

[Kevin D Pem]

I replaced my Suburban st42 water heater with a identical model. But now I'm getting error code EC. Anybody know what it could be?

This is what I pulled up on my search.

Suburban ST42 (and ST60) tankless water heaters display error codes on the user control panel to diagnose issues, with common codes including E1/E5 (ignition failure/no gas), E3 (overheat), and E6 (fan/pressure switch fault). Key fixes include resetting the unit, purging air from propane lines, checking 12VDC power, and clearing exhaust obstructions.