Troubleshoot

WARNING!
TURN OFF THE CIRCUIT BREAKER BEFORE
PROCEEDING WITH THE NEXT TESTS.
CHECKING THERMOSTATIC CIRCUIT BOARD
If the LED on the circuit board flashes one time very quickly when the water is switched ON then:
1) Turn “OFF” the power to this unit and all other units that may feed hot water to this unit.
2) Be sure that this unit is fed with cold water only. This unit must not be fed with pre-heated water
when performing this test.
3) There are six thin leads connected to the printed circuit board. Disconnect the third wire from
the left, from the top of the PCB (As indicated below) and tape off the end with insulating tape.
4) Run water from hot water faucet for 30 seconds and then switch power “ON” to the unit, with
the water flowing @ 0.75 GPM. If the light illuminates steadily then call Technical Service and
request a replacement printed circuit board (Part # EX 100). If the light still does not illuminate,
contact Technical Service and consult with a technician.
3rd wire from left3rd wire from left
7
WARNING
Do not use this unit with any pre-heated water feed if the light
has illuminated steadily having performed the above test.
The unit in this state must only
IF HAVING CARRIED OUT ALL THE TESTS LISTED ABOVE AND THE WATER
HEATING UNIT IS STILL NOT FUNCTIONING, PLEASE CALL TECHNICAL
SERVICE AT 1-800-334-3393.
PLEASE HAVE THE FOLLOWING INFORMATION AVAILABLE:
1) ORDER REF. NUMBER (Located on U.L. rating label on the front cover of unit).
2) SERIAL NUMBER (Inside unit on back plate).
be fed with cold water.