High-Efficiency Commercial Gas Series - Service Manual
Technical Literature Department
14
Ashland City, Tennessee © 2008
Servicing should only be performed by a Qualified Service Agent
Interaction with the control system is done through the
User Interface Module (UIM
).The default screen is
referred to as the
“desktop
” or “
desktop screen”
. Up
and down buttons and three operation buttons allow
navigation of the control system menus and changing
of user settings. The current function of the three
operation buttons is determined by the text displayed
on the UIM immediately above each button.
During normal operation the UIM will display the
desktop screen (if there are no active faults or
warnings).
●
An example of this screen is shown below.
●
The first temperature on this screen is the
temperature of the water inside the tank.
●
The second temperature on this screen is the
Operating Set Point
.
●
The
Operating Set Point
is the temperature at
which the water heater will maintain the water
inside the tank.
●
The third line on the screen is a text
description of the
Operational State
of the
water heater. The operating state of the water
heater is also indicated graphically by status
icons.
The table of status icons describes graphically
operational details of the water heater. Below is a
legend of all the status icons:
Status
Icon
Description
The temperature of the water in the tank has
fallen and the water heater will now initialize a
new heating cycle.
The temperature of the water in the tank has
reached the
Operating Set Point
.
The control is unable to initiate any further
heating cycles. This is usually caused by a fault
condition detected by the control, but can also
occur when an external system (like an energy
management system) has asked the water
heater to discontinue any further heat cycles.
The blower is being energized.
The blower pressure switch has been made.
The igniter has been energized.
The igniter has been energized and sufficient
current for ignition has been detected.
The control has requested that the gas valve
be turned on.
The control has sensed flame in the burner.
The control has detected a fault condition. A
fault condition will cause the water heater to
discontinue operation.
The control has detected a warning condition.
These conditions will not cause the
water heater
to discontinue further heating cycles, but does merit
attention.
CONTROL OVERVIEW
^
OPERATION
BUTTONS
UP AND
DOWN
BUTTONS
