
5-1
TROUBLESHOOTING
TANKLESS WATER HEATER 199
5.0 TROUBLESHOOTING
The troubleshooting section is divided into four sections:
5.1 Preliminary Checks
5.2 Electronic Components
5.3 Faults and Notifications
5.4 Other Faults
Often, you can identify and solve a problem through simple checks of the basics:
confirming the electrical power supply and gas flow. To help with preliminary
checks, the unit’s control module offers a visual display of the status of the various
control circuit components.
Should a problem remain unsolved after applying the preliminary checks,
proceed to the detailed system review in this guide. The Troubleshooting chapter
covers potential error conditions, grouped into the following categories:
5.3.1 Fault Codes
5.3.2 Notification Codes
5.4.1 No domestic hot water (DHW)
5.4.2 Domestic hot water does not reach the correct temperature
5.4.3 Burner ignites loudly
5.4.4 Burner resonates
Below each section is a list of symptoms, diagnoses, and solutions.
Some diagrams
(see Section 6.0)
are included for use with troubleshooting
including:
•
Electrical wiring diagrams
•
Water heater component layout diagrams
5.1 PRELIMINARY CHECKS
As a first step in troubleshooting, you should review the controller’s display
screen. Diagnostic features evaluate system integrity, display error conditions,
and indicate initial troubleshooting action.
In addition to checking the controller’s display, try these troubleshooting steps:
1.
Confirm power to the unit: check that control module display is on (e.g.,
display is lit).
2.
Check that unit is not in a safety lockout.
3.
Ensure that wiring is secure and properly terminated.
4.
Check that gas is reaching the unit.
5.
Confirm that the domestic water system pressure is a minimum 40 psig.
NOTE
This appliance is equipped
with a blocked vent shut-off
system that closes the gas
supply when it detects an
irregular venting condition.