Control And Safety Switch Adjustments; Airflow Adjustment - Trane UHMB060ACV3VA Installer's Manual

Installer's Guide
CONTROL AND SAFETY SWITCH
ADJUSTMENTS
LIMIT SWITCH CHECK OUT
The Limit Switch is a safety device designed to close
the Gas Valve should the Furnace become overheated.
Since proper operation of this switch is important to the
safe operation of the unit, it must be checked out on
initial start up by the installer.
To check for proper operation of the Limit Switches, set
the Comfort Control to a temperature higher than the
indicated room temperature to start the furnace. Re-
strict the airflow by blocking the return air (disconnect-
ing the Indoor Blower may trip the Inducer Limit).
When the Furnace reaches the maximum outlet tem-
perature as shown on the rating plate, the burners
must shut off. If they do not shut off after a reasonable
time and overheating is evident, a faulty Limit Switch
is probable and the Limit Switch must be replaced. Af-
ter checking the operation of the Limit Control, be sure
to remove the restriction from the return air inlet.

AIRFLOW ADJUSTMENT

Check inlet and outlet air temperatures to make sure
they are within the range specified on the Furnace rat-
ing nameplate. If the airflow needs to be increased or
decreased, see the Airflow Label on the Furnace or the
unit's Service Facts for information on changing the
speed of the Blower Motor for your specific model.
Blower speed changes are made on the User Interface.
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WARNING
!
ELECTRICAL SHOCK HAZARD
DO NOT TOUCH ANY COMPONENTS OTHER THAN
THE DISPLAY ASSEMBLY AND THE DOOR SWITCH
DURING THIS PROCEDURE.
FAILURE TO FOLLOW WARNING COULD RESULT IN
SERIOUS PERSONAL INJURY OR DEATH.
52
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WARNING
!
ELECTRICAL SHOCK HAZARD
DISCONNECT POWER TO THE UNIT BEFORE REMOV-
ING THE BLOWER DOOR. ALLOW A MINIMUM OF 10
SECONDS FOR IFC POWER SUPPLY TO DISCHARGE
TO 0 VOLTS.
FAILURE TO FOLLOW THIS WARNING COULD RESULT
IN PROPERTY DAMAGE, PERSONAL INJURY OR
DEATH.
INDOOR BLOWER TIMING
Heating: The Integrated Furnace Control module
controls the Indoor Blower. The Blower
start is fixed at 45 seconds after ignition.
The FAN-OFF period is field selectable
via the User Interface menu at 60, 100,
140, or 180 seconds. The factory setting is
100 seconds.
Cooling: Continuous Fan mode is 50% of the cool-
ing CFM. This is a selectable range on
the Comfort Control menu.
When in communicating mode, see Use Interface Menu
in furnace Installer's Guide.
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WARNING
!
SAFETY HAZARD
MAKE SURE THAT THE BLOWER DOOR IS IN PLACE
AND NOT AJAR. DANGEROUS FUMES COULD
ESCAPE.
FAILURE TO FOLLOW WARNING COULD RESULT IN
SERIOUS PERSONAL INJURY OR DEATH.
This unit is equipped with a Blower Door Switch which
cuts power to the Furnace causing shutdown when the
door is removed. Operation with the door removed or
ajar can permit the escape of dangerous fumes. All pan-
els must be securely closed at all times for safe opera-
tion of the Furnace.
NOTE TO INSTALLER
Review the following instructions with the homeowner.
Review contents of USER'S INFORMATION MANUAL
with the homeowner.
INSTRUCTIONS TO THE HOMEOWNER
▲
WARNING
!
EXPLOSION HAZARD
In the event that electrical, fuel, or mechanical
failures occur, shut off the gas supply off at the
manual gas valve, located on the supply gas
piping coming into the furnace, before turning off
the electrical power to the furnace. Contact the
service agency designated by your dealer.
18-CD30D1-9