Abnormal Conditions - American Standard CUX1B040A9241A Installation, Operation And Maintenance Manual

INDOOR BLOWER TIMING
Heating: The integrated furnace control controls the indoor blower.
The blower start is fixed at 45 seconds after ignition. The FAN-
OFF period is field selectable by dip switches at 60, 100, 140, or
180 seconds. The factory setting is 100 seconds (See wiring
diagram).
Cooling: The fan delay off period is factory set at 0 seconds. The
option for 80 second delay off is field selectable (See wiring
diagram).
ROOM AIR THERMOSTAT HEAT ANTICIPATOR
ADJUSTMENT
Set the thermostat heat anticipator according to the current flow
measured, or the settings found in the notes on the furnace wiring
diagram (found in the SERVICE FACTS or inside the furnace
casing).
INSTRUCTIONS TO THE OWNERS
▲
WARNING
!
EXPLOSION HAZARD
In the event that electrical, fuel, or mechanical fail-
ures 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.
BURNER BOX TEMPERATURE LIMIT DEVICE
All models are equipped with a manual reset temperature limit
located on the burner box. In case of excessive temperature, the
limit will open and cause the circuit to open which shuts off all flow
of gas.

ABNORMAL CONDITIONS

1. EXCESSIVE COMBUSTION PRESSURE (WIND IN
EXCESS OF 40 M.P.H.) VENT OR FLUE BLOCKAGE
If pressure against induced draft blower outlet becomes exces-
sive, the pressure switch will open and shut off the gas valve until
acceptable combustion pressure is again available.
2. LOSS OF FLAME
If loss of flame occurs during a heating cycle, or flame is not
present at the sensor, the flame control module will close the gas
valve. The flame control module will then recycle the ignition
sequence, then if ignition is not achieved, it will shut off the gas
valve and lock out the system.
3. POWER FAILURE
If there is a power failure during a heating cycle, the system will
restart the ignition sequence automatically when power is re-
stored, if the thermostat still calls for heat.
4. GAS SUPPLY FAILURE
If loss of flame occurs during a heating cycle, the system inte-
grated control module will recycle the ignition sequence, then if
ignition is not achieved, the integrated control module will shut
off the gas valve and lock out the system.
5. INDUCED DRAFT BLOWER FAILURE
If pressure is not sensed by the pressure switch, the contacts will
remain open and not allow the gas valve to open, therefore the unit
will not start. If failure occurs during a running cycle, the pressure
switch contacts will open and the gas valve will close to shut the
unit down.
Pub. No. 41-5016-12
.
Installation Instructions
The following warning complies with State of California law, Proposition 65.
▲
WARNING
!
This product contains fiberglass wool insulation!
Fiberglass dust and ceramic fibers are believed by the
State of California to cause cancer through inhalation.
Glasswool fibers may also cause respiratory, skin, or
eye irritation.
PRECAUTIONARY MEASURES
●
Avoid breathing fiberglass dust.
●
Use a NIOSH approved dust/mist respirator.
●
Avoid contact with the skin or eyes. Wear long-sleeved,
loose-fitting clothing, gloves, and eye protection.
●
Wash clothes separately from other clothing: rinse
washer thoroughly.
●
Operations such as sawing, blowing, tear-out, and
spraying may generate fiber concentrations requiring
additional respiratory protection. Use the appropriate
NIOSH approved respirator in these situations.
FIRST AID MEASURES
Eye Contact – Flush eyes with water to remove dust.
If symptoms persist, seek medical
attention.
Skin Contact – Wash affected areas gently with soap
and warm water after handling.
6. CONDENSATE DRAIN BLOCKAGE
If the condensate drain is blocked, either by debris, improper
draining, or by freezing condensate, the pressure switch will
receive a signal warning of the accumulation of condensate in the
heat exchanger assembly. The pressure switch contacts will open
and remain open, not allowing unit operation. The unit will not
operate until the condensate drain has been cleared, and the
condensate flows freely.
7. RESET AFTER LOCKOUT
When the integrated control module has shut the system down
and gone into lockout, the system must be manually reset before
the unit will restart. To reset, turn the system power off, then on,
then off and then on again within 30 seconds. This may be done
at the unit's power source or at the thermostat. The system will not
reset unless the procedure off-on-off-on is completed within 30 sec-
onds.
8. RESET AFTER BURNER BOX LIMIT SHUTDOWN
If the furnace shuts down, one thing that can be checked is the
burner box temperature limit switch. It is located on the bottom
of the burner box. The vent and combustion air inlet terminations
should be checked for blockage. If blockage exists, clear the prob-
lem and then the reset button may be depressed. If there is no
blockage of the terminations, the limit switch must be reset
by a qualified servicer.
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