Bryant FA4A - Manual (Page 20)

A U G / 1 4 / 2 0 0 8 / T H U 0 3 : 5 0 UTC TECH PUB F A X N o , 3 1 7 2 4 0 5 6 6 2 P .
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 enfirgjitd which closes contacts of relay. There
will be a time delay. This completed circuit enejgijes all heating
elements HTR and blower motor.
B, Heat Pump
COOLING
On a call for cooling, the thermostat makes circuits R-0, R-Y, and
R“Q. Circuit R-0 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 nibtofs.
HEATING
On a call for heating, the thonnostat 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 faIl„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-enftrgiiing
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 Eltor 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.
A
WARNING: As with any mechanical equipment, per­
sonal injury can result fi:om sharp metal edges. Be careful
when removing parts.
A. Air Filter
To clean or replace air filter, grasp it at bottom and lift it out of
unit. Clean filter using cold water. Rinse clean and let dry. Oiling
or coating of filter is not required. To replace, stand filter in rack
with binding facing coil. Press top edge under access panel.
NOTE: Steel rods in filter prevent it from being pulled into coil.
Retain these rods and reinstall after cleaning or before replacement
if new filter is used.
A CAUTION; Never operate unit without a filter.
B. Cooling Coil, Drain Pan, and Condensate Drain
The cooling coil is easily cleaned when it is dry. Inspect coil and
clean (if necessary) before each cooling season. To check or clean
cooling coil, remove blowcr/hcatcr access panel to gain full access
to cooling coil- If coil is coated with dirt or lint, vacuum with a soft
brush attachment.
Be careful not to bend coil fins. If coil is coated with oil or grease,
clean it with a mild detergent-and-water solution. Rinse coil with
clear water. Be cajcfol not to splash water onto insulation.
Inspect drain pan and condensate drain at same time cooling coil
is checked. Clean drain pan and condensate drain by removing any
foreign matter from pan. Flush pan and drain tube with clear water.
If drain tube is restricted, it- can generally be cleared by high-
pressure water. Cut plastic line and work outside condensate pan
and away from coil to clear drain tube.
NOTE: There MUST be a trap in condensate line. Trap must be
at least 3-in. deep, not higher than the bottom of unit condensate
drain opening, and pitched downward to an open drain or sump.
A
CAUTION: Do not use caustic household drain cleaners
in condensate pan or near coil. Drain cleaners can quickly
destroy coils.
C. Blower Motor and Wheel
Clean blower motor and'wheel when cooling coil is-cleaned.
To clean or service wheel or motor, proceed as follows:
1. Pull unit disconnect (when used) and remove blower access
panel.
2. Disconnect motor electrical leads from control box and
capacitor. Mark location of wires for reassembly.
3. Remove 3 bolts holding motor mount to blow'er bousing
while supporting motor shell with hand.
4. Pull motor inlet ring and blower wheel assembly out of
blower housing.
5. With blower wheel, inlet ring, and motor mount still
attached to motor, place motor on flat, horizontal surface,
shaft up, Mark position of wheel on motor shaft for
reassembly.
6. Loosen blower wheel setscrew and remove blower wheel
from motor shaft.
NOTE: Further disassembly of motor and mount is not necessary
■ as adequate clearance is available to clean motor.
7. Qean blower motor and wheel using a vacuum with a soft
brush attachment- Remove grease with a mild solvent such
as hot water and detergent. Be careful not to disturb balance
weights (clips) on blower wheel vanes. Do not drop or bend
wheel as balance will be affected.
To reassemble unit, proceed as follows;
1. Place motor with mount attached on flat, horizontal surface
with shaft up-
2. Sef inlet ring 6n fop of motor mount grommets/ Center inlet
ring flush on all 3 grommets.
3. Slide blower wheel onto motor shaft with setscrew upward
and aligned with shaft flat portion. Vertically position
wheel along shaft to position marked during disassembly.
NOTE: If previous shaft was not marked or if replacing previous
motor, set blower wheel position by sliding blower wheel along
motor shaft to 1-1/8 in, above rubber grommets. (See Fig, 17,)
4. Hold blower wheel in place and carefully tighten setscrew,
5. Position motor and blower wheel assembly to blower
housing as originally oriented.
6. Secure motor mount to blower housing using bolts previ­
ously removed.
7. Attach green wire to blower housing with screw.
8. Connect electrical and capacitor leads to original terminals.
9. Replace blower access door and tighten all 4 screws,
10. Reinsert disconnect pullout only after blower access door is
secured. Test blower for proper operution.
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