TR
OUBLE
SHOO
TING
18 • Electric Tankless Water Heater
Flash Code
Sequence
Description
Action / Solution
18
Moisture detected
Shut o
ff
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 su
ffi
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-o
ff
valve.
22, 24, 25, 31,
32, 34, 35
Data reading error
Reset the water heater. Turn o
ff
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 .
