1. Inspect air filter(s) each month. Clean or replace when
necessary.
2. Inspect indoor coil, drain pan, and condensate drain at least
each cooling season for cleanliness. Clean when necessary.
3. Inspect blower motor and wheel for cleanliness and check
lubrication each heating and cooling season. Clean when
necessary.
4. Check electrical connections for tightness and controls for
proper operation each heating and cooling season. Service
when necessary.
5. Ensure electric wires are not in contact with refrigerant
tubing or sharp metal edges.
A.
AIR FILTER
CAUTION:
Never operate the unit without a suitable air
filter in the return-air duct system. Always replace the
filter with the same size as originally installed. See Table
1 for recommended filter sizes.
Inspect air filter(s) at least once each month and replace
(throwaway-type) or clean (cleanable-type) at least twice during
each heating and cooling season or whenever the filter(s) becomes
clogged with dust and lint.
B.
UNIT TOP REMOVAL
NOTE:
When performing maintenance or service procedures that
require removal of the unit top, be sure to perform all of the routine
maintenance procedures that require top removal, including coil
inspection and cleaning, and condensate drain pan inspection and
cleaning.
Only qualified service personnel should perform maintenance and
service procedures that require unit top removal. Refer to the
following top removal procedures:
1. Remove 7 screws on unit top cover surface. (Save all
screws.)
2. Remove 4 screws on unit top cover flange. (Save all
screws.)
3. Lift top from unit carefully. Set top on edge and make sure
that top is supported by unit side that is opposite duct (or
plenum) side.
4. Carefully replace and secure unit top to unit, using screws
removed in Steps 1 and 2, when maintenance and/or service
procedures are completed.
C.
INDOOR BLOWER AND MOTOR
NOTE:
Motors without oilers are prelubricated. Do not attempt to
lubricate these motors.
For longer life, operating economy, and continuing efficiency,
clean accumulated dirt and grease from the blower wheel and
motor annually.
Lubricate the motor every 5 years if the motor is used intermit-
tently (thermostat FAN switch in AUTO. position), or every 2
years if the motor is used continuously (thermostat FAN switch in
ON position).
TABLE 8—DRY COIL AIR DELIVERY (DEDUCT 10 PERCENT FOR 208V)*
HORIZONTAL AND DOWNFLOW DISCHARGE
UNIT 657A024-042
230 AND 460 VOLT
Unit
Motor
Speed
External Static Pressure (in. wg)
0.0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
024 & 030
Low
Watts
280
275
265
255
250
245
240
—
—
—
—
Cfm
820
810
755
700
660
600
560
—
—
—
—
Med
Watts
365
360
350
345
340
330
320
310
300
—
—
Cfm
1025
1010
975
940
900
850
800
720
630
—
—
High
Watts
—
—
490
480
470
460
445
430
410
390
380
Cfm
—
—
1300
1255
1200
1150
1080
1005
915
790
620
036
Low
Watts
520
495
474
458
445
425
—
—
—
—
—
Cfm
1375
1335
1290
1240
1200
1140
—
—
—
—
—
Med
Watts
575
560
535
510
480
460
440
425
—
—
—
Cfm
1520
1490
1450
1400
1380
1300
1200
1080
—
—
—
High
Watts
—
—
—
—
650
614
575
540
510
480
—
Cfm
—
—
—
—
1560
1500
1380
1280
1170
1060
—
042
Low
Watts
490
480
470
460
450
430
410
390
—
—
—
Cfm
1400
1380
1340
1300
1250
1200
1140
1070
—
—
—
Med
Watts
590
580
560
545
525
505
480
450
420
—
—
Cfm
1600
1560
1540
1470
1430
1360
1300
1220
1120
—
—
High
Watts
—
—
—
—
—
700
670
640
600
560
500
Cfm
—
—
—
—
—
1780
1670
1600
1480
1340
1100
* Air delivery values are based on operating voltage of 230-v dry coil, without filter or electric heater. Deduct wet coil, filter and electric heater pressure drops to obtain static
pressure available for ducting.
NOTES:
1. Do not operate the unit at a cooling airflow that is less than 350 cfm for each 12,000 Btuh of rated cooling capacity. Indoor coil frosting may occur at airflows below this
point.
2. Dashes indicate portions of table that are beyond the blower motor capacity or are not recommended.
TABLE 9—048 & 060 ECM AIRFLOW (CFM)
UNIT 657A
FAN ONLY
(CFM)
COOLING
(CFM)
048
1400
1600
060
1750
2000
—24—
