5169032-UIM-C-0416
18
Johnson Controls Unitary Products
SECTION XIII: MAINTENANCE
Filters must be cleaned or replaced when they become dirty. Inspect at
least once per month. The frequency of cleaning depends upon the
hours of operation and the local atmospheric conditions. Clean filters
keep unit efficiency high.
COIL CLEANING
If the coil needs to be cleaned, it should be cleaned with water.
LUBRICATION
The bearings of the blower motor are permanently lubricated.
CONDENSATE DRAINS
During the cooling season check the condensate drain lines to be sure
that condensate is flowing from the primary drain but not from the
secondary drain. If condensate ever flows from the secondary drain the
unit should be promptly shut off and the condensate pan and drains
cleaned to insure a free flowing primary drain.
SECTION XIV: AIR SYSTEM ADJUSTMENT
To check the Cubic Feet per Minute (CFM), measure the external duct
static using a manometer and static pressure tips. To prepare coil for
static pressure measurements run the fan only to assure a dry coil.
Drill 2 holes, one 12” away from the air handler in the supply air duct
and on 12” away from the air handler in the return air duct (before any
elbows in the duct work). Insert the pressure tips, and energize the
blower motor. See Table 9 to determine the air flow, and make the
necessary adjustments to keep the CFM within the airflow limitations of
the coil.
EXTERNAL DUCT STATIC
Measure the supply air static pressure. Record this positive number.
Measure the return air static pressure. Record this negative number.
Treat the negative number as a positive, and add the two numbers to-
gether to determine the total external system static pressure. If a filter
rack is installed on the return air end of the air handler or indoor coil sec-
tion, make sure to measure the return air duct static between the filter
and the indoor coil.
48C
#5 HI
1759
1719
1685
1644
1611
1578
1540
#4 MED-HI
1684
1639
1606
1569
1536
1489
1452
#3 MED
1511
1460
1427
1388
1347
1308
1262
#2 MED-LO
1305
1260
1212
1178
1121
1076
1027
#1 LO
1123
1068
1029
985
909
793
769
48D
#5 HI
1774
1726
1684
1651
1614
1574
1529
#4 MED-HI
1709
1668
1619
1580
1548
1499
1459
#3 MED
1484
1436
1410
1372
1321
1284
1237
#2 MED-LO
1295
1254
1218
1167
1114
1069
1005
#1 LO
1102
1051
1011
962
890
831
766
60C
#5 HI
1964
1930
1897
1858
1823
1789
1752
#4 MED-HI
1889
1855
1818
1791
1747
1716
1668
#3 MED
1693
1652
1627
1584
1551
1510
1462
#2 MED-LO
1486
1450
1411
1375
1335
1291
1252
#1 LO
1292
1247
1207
1172
1123
1055
990
60D
#5 HI
1907
1871
1835
1796
1762
1723
1681
#4 MED-HI
1851
1816
1774
1742
1699
1659
1616
#3 MED
1648
1608
1569
1530
1492
1445
1404
#2 MED-LO
1456
1416
1371
1333
1289
1227
1163
#1 LO
1261
1221
1172
1120
1055
998
949
1. Air handler units have been tested to UL 1995 / CSA 22.2 standards up to 0.50" wc. external static pressure.
Dry coil conditions only, tested without filters.
For optimal performance, external static pressures of 0.2" to 0.5" are recommended. Applications above 0.5" are not recommended.
Airflow data shown is from testing performed at 230V. AE units use a standard ECM constant torque motor, and there is minimal variation of airflow at other distribution
voltage values. The above data can be used for airflow at other distribution voltages.
TABLE 11:
Air Flow Data (CFM)
1
Models
Blower
Motor Speed
External Static Pressure (in. wc.)
0.10
0.20
0.30
0.40
0.50
0.60
0.70
NOTICE
Refer to Table 11 for coil Air Flow Data of Cubic Feet Per Minute
(CFM).