Service Instructions

SERVICING
111
pressure external to the unit. The installation manual supplied
with the blower coil, or the blower performance table in the
service manual, shows the CFM for the static measured.
Alternately, the system CFM can be determined by operating the
electric heaters and indoor blower WITHOUT having the com-
pressor in operation. Measure the temperature rise as close to
the blower inlet and outlet as possible.
If other than a 240V power supply is used, refer to the BTUH
CAPACITY CORRECTION FACTOR chart below.
BTUH CAPACITY CORRECTION FACTOR
SUPPLY VOLTAGE 250 230 220 208
MULTIPLICATION FACTOR 1.08 .92 .84 .75
EXAMPLE: Five (5) heaters provide 24.0 KW at the rated 240V. Our
actual measured voltage is 220V, and our measured temperature
rise is 42°F. Find the actual CFM:
Answer: 24.0KW, 42°F Rise, 240 V = 1800 CFM from the TEMPERA-
TURE RISE chart on the right.
Heating output at 220 V = 24.0KW x 3.413 x .84 = 68.8 MBH.
Actual CFM = 1800 x .84 Corr. Factor = 1400 CFM.
NOTE: The temperature rise table is for sea level installations.
The temperature rise at a particular KW and CFM will be greater
at high altitudes, while the external static pressure at a particular
CFM will be less.
CFM
3.0
kW
4.8
kW
7.2
kW
9.6
kW
14.4
kW
19.2
kW
24.0
kW
28.8
kW
60016253851----
70014223343----
800 12 19 29 38 57 - - -
900 11 17 26 34 51 - - -
1000 10 15 23 30 46 - - -
1100 9 14 21 27 41 55 - -
1200 8 13 19 25 38 50 - -
1300 7 12 18 23 35 46 - -
1400 7 11 16 22 32 43 54 65
1500 6 10 15 20 30 40 50 60
1600 6 9 14 19 28 38 47 57
1700 6 9 14 18 27 36 44 53
1800 5 8 13 17 25 34 42 50
1900 5 8 12 16 24 32 40 48
2000 5 8 12 15 23 30 38 45
2100 5 7 11 14 22 29 36 43
2200 4 7 11 14 21 27 34 41
2300 4 7 10 13 20 26 33 39
TEMPERATURE RISE (°F) @ 240V
HTR
KW
3.0
KW
4.7
KW
6.0
KW
7.0
KW
9.5
KW
14.2
KW
19.5
KW
21.0
KW
BTUH 10200 16200 20400 23800 32400 48600 66500 71600
ELECTRIC HEATER CAPACITY BTUH
FORMULAS:
Heating Output = KW x 3413 x Corr. Factor
Actual CFM = CFM (from table) x Corr. Factor
BTUH = KW x 3413
BTUH = CFM x 1.08 x Temperature Rise (T)
CFM = KW x 3413
1.08 x T
T = BTUH
CFM x 1.08
S-61ACHECKING HEATER LIMIT CONTROL(S)
Each individual heater element is protected with a limit control
device connected in series with each element to prevent overheat-
ing of components in case of low airflow. This limit control will
open its circuit at approximately 150°F.
WARNING
HIGH VOLTAGE!
Disconnect ALL power before servicing
or installing. Multiple power sources
may be present. Failure to do so may
cause property damage, personal injury
or death.
1. Remove the wiring from the control terminals.
2. Using an ohmmeter, test for continuity across the normally
closed contacts. No reading indicates the control is open -
replace if necessary.
IF FOUND OPEN - REPLACE - DO NOT WIRE AROUND.
S-61BCHECKING HEATER FUSE LINK
(OPTIONAL ELECTRIC HEATERS)
Each individual heater element is protected with a one time fuse
link which is connected in series with the element. The fuse link
will open at approximately 333°.
Disconnect ALL power before servicing.
WARNING