Fault codes / Suburban tankless / EC

Suburban tankless code EC

What it means: Lost communication with the controller.

What to check

Check the display cable at both ends.

Learn the system

• Tank water heaters
• Tankless water heaters
• Water heater gas side

Practice it on a service call

• No hot water on electric
• Water heater lights, then goes out
• Water heater lights then faults

Guided diagnosis

• Water Heater

Other Suburban tankless codes

• Suburban tankless code E0 Outlet temperature probe open or shorted
• Suburban tankless code E1 Ignition failure: no flame after 3 tries
• Suburban tankless code E2 False flame: flame sensed before startup
• Suburban tankless code E3 High limit (ECO) tripped
• Suburban tankless code E4 Inlet temperature sensor open or shorted
• Suburban tankless code E5 Fan failure: no speed signal
• Suburban tankless code E6 Over temperature at the outlet
• Suburban tankless code E7 Gas valve circuit open or shorted
• Suburban tankless code E8 Pressure switch stuck closed or disconnected
• Suburban tankless code E9 Recirculation pump will not prime (RL models)
• Suburban tankless code En Ran continuously for more than 20 minutes

Full field guide: Suburban IW60 and ST tankless water heater

Codes come from the maker manuals and public service sheets. Your model's own chart always wins, and LP and 120 volt work belongs to a qualified technician.