Service Manual

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Introduction
The Ultra High Efficiency Water Heater is designed to deliver a high thermal efficiency rating in a
quiet running unit with venting options that allow for installation flexibility. Several technologically
advanced design features are incorporated in the design that will require additional knowledge on
the part of the qualified service provider. The information in this manual will instruct service and
maintenance professionals on the function, proper diagnosis and repair of The Ultra High Efficiency
Water Heater.
The Ultra High Efficiency Water Heater uses a Low NOx premix power burner located at the top of
the water heater to direct a turbulent flame down into a submerged combustion chamber. This
turbulence causes a thorough mixing of gas and air for optimum combustion. The combustion gases
then travel through a three-pass flue system keeping the gases moving at a high velocity. The
combination of high turbulence and velocity results in an optimum transfer of heat from the flue
gases into the water.
Burner operation is controlled using an electronic ignition module. The module monitors the status of
the electronic thermostat, vent temperature limit switch, vent system pressure switches, a flame
sensor to control output voltage to blower motor, igniter/spark rod, and gas valve. The module
contains programming which determines the sequence of operation and timings for purge periods,
trial for ignition, flame sensing, and lockout. The module will also provide diagnostic information to
help in determining the cause of system lockouts.
The contents in this manual are detailed informational tools to assist in the proper diagnosis of the
Ultra High Efficiency Water Heater operational faults. Please read this service manual completely
and provide as much information regarding the Ultra High Efficiency Water Heater operation and
installation specific concerns.
How to Use this Manual
It is intended for this manual to be used by qualified service personal for the primary purpose of
troubleshooting analysis and repair of the Ultra High Efficiency Water Heater. Understanding the
sequence of operation section of this manual will contribute greatly to troubleshooting this product.
An Installation Checklist is shown towards the end of this manual. Compare the installation against
the installation check list to confirm all requirements are met.
A Service Report is shown towards the end of this manual. Completing this form will assist in
the troubleshooting efforts. Should you need to call for technical support, p lease provide the
information shown on this form to the support technician to insure accurate troubleshooting.
Troubleshooting begins with System Observation to determine failure mode as indicated by the
LED status of the ignition module. Troubleshooting continues with Failure Modes and Probable
Cause, directing the service provider to a series of test procedures to determine root cause of
failure. Component replacement procedures directly follow the test procedures for a given
component.
In some difficult to diagnose conditions, it may be necessary to isolate the heater from the vent
system to determine root cause. Contact Technical Support immediately if diagnosis is not
determined using the methods described in this Service Manual.
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