Installation Guide

TROUBLESHOOTING
18 • Electric Tankless Water Heater
Flash Code
Sequence
Description Action / Solution
18 Moisture detected Shut off all power to the water heater. Check for water leaks. Correct any
leaks found. Dry the control board completely before restoring power.
21 Level Detect Ensure that the heater is fi lled with water and that there is no air trapped
inside. Check the opera on of back fl ow preventer or check valve. If the
heater is fi lled and there are no leaks, connect level detect spades on the
circuit board to ground. If the code is accompanied by a clicking sound
that is present when water is running, check the elements.
23 No temperature rise (water is not
being heated suffi ciently)
Check elements. Check temperature sensors. Check wiring and circuit
breakers. Verify proper heater sizing. If necessary, reduce the unit tem-
perature from maximum se ng and reduce fl ow rate with shut-off valve.
22, 24, 25, 31,
32, 34, 35
Data reading error Reset the water heater. Turn off all circuit breakers to the heater for
approx. 30 seconds. Turn on breakers. The LED should fl ash all green
and the heater should produce hot water. If the code persists, reset the
breakers again. If that does not work, test the temperature sensors. Re-
place the temperature sensors and/or circuit board as needed.
LED STATUS LAMP
INTERNAL CIRCUIT BOARD
MODE BUTTON:
(PRESS FOR TWO
SECONDS TO TURN
AUDIBLE BEEPER
ON)
PLUMBING CONNECTIONS
BEHIND CIRCUIT BOARD
REQUIRED JUMPERS (2)
TOP OF INTERNAL CIRCUIT BOARD
OPEN PINS (3)
Figure 8 .