Electric heating tube does not work
Fault — the ESS unit enters fault protection and stops normal operation until the fault is cleared — how it is shown (LED pattern or display code) depends on the model.
Electric heating tube does not work
Cause: Water temperature set too low (no heating required), loose circuit connection, or electric heating tube burnout.
Check outlet temperature and heating set point; tighten circuit connector; replace burnt-out heating tube.
Source: fls-es232lc-g-2-fls-es232lc-s-user-guide-en.pdf
HVAC-HEAT-NOWORK means: Electric heating tube does not work. Water temperature set too low (no heating required), loose circuit connection, or electric heating tube burnout.
HVAC-HEAT-NOWORK is a fault code: the ESS unit enters protection and stops normal operation until it is cleared.
Check outlet temperature and heating set point; tighten circuit connector; replace burnt-out heating tube.
Prefer the full written guide? Read the complete Felicity inverter error-code guide
Compiled from official Felicity user manuals. Always consult your device manual and a qualified technician before performing repairs.