Stand-Alone Operation - American Standard UHMB060ACV3VB Series Service Facts

STAND ALONE OPERATION
(CONTINGENCY MODE)
The Contingency Mode allows the installer to set the
equipment to operate in an ON/ OFF Duty Cycle mode.
This mode will be activated using the User Interface.
Contingency Mode is NOT available in 24VAC mode.
The user will select the desired level of capacity
required, Stage 1 (40%) or 2 (100%). The user will
select the desired ON/ OFF Duty Cycle, 10% minimum
to 50% maximum, (10% increments, 10% = 2 minutes
On, 18 minutes Off; 50% = 10 minutes on, 10 minutes
off).
CONTINGENCY MODE
Note:
Stage 1 = 40% (low) heat, Stage 2 = 100% (high) heat
Note:
If a communicating comfort control is detected to be
present and the contingency mode is selected,
NOT AVAILABLE will be displayed on the User
Interface.
•
Stand alone operation can only be entered at the
user interface.
• Stand alone operation can be set up to operate the fur-
nace in Heating Only.
•
The contingency mode is used when the communi-
cating comfort Control is not communicating with
the furnace or when setting gas manifold pressures.
•
Before attempting to enter contingency mode,
disconnect the Data wire "D" from the Furnace IFC ter-
minal block.
•
The contingency mode will function only when the
Furnace IFC is not flashing a fault code at its
Fault LED.
•
To enter the contingency mode of operation, turn 115
VAC power off. When the Green LED on the variable
speed inducer drive goes out, turn 115 VAC power
back on.
•
Scroll down using the down arrow  at the User
Interface until you see CNTNGNCY Mode, then
press the Enter button.
• CNTNGNCY MODE and  STAGE  will now
be displayed. Press the Enter button.
•
STAGE and OFF [OFF] will now be displayed.
First or Second heat stage must be select-
ed. Use the or arrows to select the stage
of heat wanted and then push the Enter button
and then the  button.
•
DUTY CYCLE and 10% [10%] will now be displayed. A
duty cycle must now be selected from 10 to 50%. A
10% duty cycle will run the furnace for 2 minutes and
then off for 18 minutes. A 50% duty cycle will run the
furnace for 10 minutes and then be off for 10 minutes.
These duty cycles will be repeated 3 times per hour.
Use the or arrows to select a duty cycle and then
push the Enter button and then the  button.
•
Start and NO [NO] will now be displayed. With a NO/
NO question being asked, use the or arrows to
select the YES and then press the ENTER button.
UHM-DHM-SF-1V-EN
Service Facts
•
Are you Sure and NO [NO] will now be displayed.
With a NO/ NO question being asked, use the or
arrows to select the YES and then press the ENTER
button.
•
Turn 115VAC power off. When the Green LED on
the variable speed inducer drive goes out, turn
115 VAC power back on.
•
When the furnace is operating in the contingency
mode (stand alone operating cycle), the user inter-
face will display the following information. The top
line will say CNTNGNCY MODE. The bottom line
will show the duty cycle stage number STG (1 or 2)
selected, and the percent number 10-50 % selected.
•
All furnace operating controls, pressure switches and
communications between the IFC and the variable
speed inducer drive and the variable speed indoor
blower will be functional during contingency mode
operation of the furnace.
• The  and ENTER buttons do not function in
the contingency mode of operation.
•
To exit the contingency mode of operation turn
off the 115 VAC power to the furnace.
•
The contingency mode will stop for any of the follow-
ing reasons:
(1) If the furnace IFC receives a signal from the
communicating comfort control. This will only hap-
pen if the data wire "D" from the comfort control has
been reconnected to the furnace IFC terminal board
terminal "D".
(2) Power is removed from the furnace and then
turned back on.
(3) The Furnace IFC enters a RESET mode of op-
eration.
(4) A fault is detected by the furnace IFC. Fault LED
will be flashing an Alert Code.
24V CONTINGENCY MODE
An alternative method for the contingency mode can be
used by changing the mode of operation in the Use
Interface to 24V mode and installing a conventional
24V comfort control.
To set this mode of operation:
Remove all wiring from the *CONT900 comfort control
and install a 24V comfort control.
control requires a 24V common; connect R and B
to respective terminals. Connect a third wire to "W".
At the control board, connect the same three wires
to the corresponding terminals. Jumper W1 to W2 at
the control board. The stage delay between W1 and
W2 can be set by scrolling thru the User Interface. It
is factory set to zero minutes but can be adjusted to
5, 10, or 15 minutes.
If the comfort
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