Ff1A/Ff1B/Ff1C Service And Troubleshooting; Fan Motor; Electric Heater Service; Cleaning Or Replacing Refrigerant Flow-Control Device - Bryant SM03-4 Service Manual

2. Reassemble cutoff plate to housing using identified holes
from disassembly procedure.
3. Position motor and mount in same position as when blower
housing was in unit. Secure motor mount on housing, using
removed bolts. Make sure mount or motor is grounded to
blower housing.
4. Locate blower wheel setscrew over flat on motor shaft.
Rotate wheel in housing. It should not rub housing and
should be centered in inlet opening. If not, loosen setscrew
and align as necessary.
5. Attach green wire to blower housing with screw.
6. Secure motor capacitor under strap and tighten strap screw.
7. Slide blower assembly to blower deck. Be sure (once
blower is within the unit casing) to force blower assembly
toward control box while sliding assembly into unit to
ensure that blower assembly engages deck properly.
8. Fasten blower assembly to deck with screws previously
removed.
9. Reconnect electrical leads to PCB.
10. Reconnect electrical power to unit and test fan for proper
rotation.

FF1A/FF1B/FF1C SERVICE AND TROUBLESHOOTING

NOTE: For FF1D Service and Troubleshooting refer to FA4A,
FB4A, FF1D, FH4A, AND FX4A Circuit Board Function and
Troubleshooting on page 2. (For FF1D typical wiring diagram, see
Fig. 3B.)
WARNING: Before installation or servicing system,
always turn off main power to system. There may be
more than 1 disconnect switch. Turn off accessory heater
power if applicable. Electrical shock can cause personal
injury or death.
I. FAN MOTOR
The motor is 2-speed direct drive. High-speed lead is black,
low-speed lead is red, and common lead is violet. Be sure proper
blower speed has been selected. For units with electrical heat,
low-speed tap can be used. For cooling, use high-speed tap.
The motor is turned on through 2 different routes. The first occurs
when thermostat calls for the fan in cooling, heat pump, or
fan-only mode. A 24-vac signal is sent to relay, causing relay to
close its normally-open contacts, turning fan on. The second
occurs when there is a call for electric heat. A 24-vac signal is sent
to heater sequencer/relay, causing it to close, directing 230v
through the normally-closed contact of fan relay, turning fan on.
The fan remains on until sequencer/relay opens. Refer to
FF1A/FF1B/FF1C typical wiring diagram. (See Fig. 33.)
If motor does run, test motor for an open winding or a winding
shorted to motor case. If any 1 of the 2 is present, replace motor.
II. ELECTRIC HEATER SERVICE
Service can be completed with heater in place. Shut off power
before servicing.
A. Limit Switch
Refer to Electric Heater Function and Troubleshooting section of
this manual.
B. Sequencer
Refer to Electric Heater Function and Troubleshooting section of
this manual.
C. Transformer
A 40-VA transformer supplies 24-v power for control circuit.
Check for 208/230v on primary side of transformer. If present,
check for 24v on secondary side.
NOTE: Transformer is fused. Do not short circuit.
D. Fan Relay
Relay coil is 24 volts. Check for proper control voltage. Replace
relay if faulty.
III. CLEANING OR REPLACING REFRIGERANT FLOW-
CONTROL DEVICE
Refer to Fig. 30 and instructions given in Piston Body Cleaning or
Replacement section above.
IV. LIQUID TUBE STRAINER
The refrigerant flow-control device is protected by a wire mesh
strainer. It is located inside the 3/8-in. liquid tube at field braze
joint next to flow-control device. Access to strainer is through field
braze joint.
V. SEQUENCE OF OPERATION
Refer to Fig. 33.
A. Condensing Unit
COOLING
When thermostat calls for cooling, the circuit between R and G is
complete and single-pole single-throw relay FR is energized. The
normally-open contacts close causing blower to operate. The
circuit between R and Y is also complete. This completed circuit
causes contactor in outdoor unit to close which starts compressor
and outdoor fan.
HEATING
When thermostat calls for heating and FAN switch is set on
AUTO, the circuit between R and W is complete. The heater
sequence SEQ is energized which closes contacts of relay. There
will be a time delay. This completed circuit energizes all heating
elements HTR and blower motor.
B. Heat Pump
COOLING
On a call for cooling, the thermostat makes circuits R-O, R-Y, and
R-G. Circuit R-O energizes reversing valve, switching it to cooling
position. Circuit R-Y energizes contactor starting outdoor fan
motor and compressor. Circuit R-G energizes indoor unit blower
relay starting indoor blower motor. When thermostat is satisfied,
its contacts open de-energizing contactor reversing valve and
blower relay. This stops compressor and fan motors.
HEATING
On a call for heating, the thermostat makes circuits R-Y and R-G.
Circuit R-Y energizes contactor starting outdoor fan motor and
compressor. Circuit R-G energizes indoor blower relay starting
blower motor. Should temperature continue to fall, R-W circuit is
made through second-stage room thermostat bulb. Circuit R-W
energizes a sequencer bringing on supplemental electric heat.
When thermostat is satisfied, its contacts open de-energizing
contactor and sequencer. All heaters and motors should stop.
VI. CARE AND MAINTENANCE
The minimum maintenance requirements for this equipment are as
follows:
1. Inspect and clean or replace air filter each month or as
required.
2. Inspect cooling coil, drain pan, and condensate drain each
cooling season for cleanliness. Clean as necessary.
3. Inspect blower motor and wheel for cleanliness each
heating and cooling season. Clean as necessary.
4. Inspect electrical connections for tightness and controls for
proper operation each heating and cooling season. Service
as necessary.
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