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TSA*H4 SERIES
Start−Up and Charging Procedures
IMPORTANT
If unit is equipped with a crankcase heater, it should
be energized 24 hours before unit start−up to
prevent compressor damage as a result of slugging.
1. Rotate fan to check for binding.
2. Inspect all factory− and field−installed wiring for loose
connections.
3. After evacuation is complete, open both the liquid and
suction line service valves to release the refrigerant
charge contained in the outdoor unit into the system.
4. Replace the stem caps and tighten to the value listed
in table 1.
5. Check voltage supply at the disconnect switch. The
voltage must be within the range listed on the unit’s
nameplate. If not, do not start the equipment until you
have consulted with the power company and the
voltage condition has been corrected.
6. Set the thermostat for a cooling demand. Turn on
power to the indoor indoor unit and close the outdoor
unit disconnect switch to start the unit.
7. Recheck voltage while the unit is running. Power must
be within range shown on the nameplate.
8. Check system for sufficient refrigerate by using the
procedures listed under
Testing and Charging
System
.
SETTING UP TO CHECK CHARGE
1. Close manifold gauge set valves. Connect the center
manifold hose to an upright cylinder of HFC−410A.
2. Connect the manifold gauge set to the unit’s service
ports as illustrated in figure 1.
low pressure gauge to suction line service port.
high pressure gauge to liquid line service port.
INDOOR COIL AIRFLOW CHECK
Check indoor coil airflow using the Delta−T (
D
T)
process
as illustration in figure 27.
DETERMINING CHARGE METHOD
To determine the correct charging method, use the
illustration in figure 27.
1. Determine the desired
D
T
Measure entering air temperature
using dry bulb (
A
) and wet bulb (
B
).
D
T
is the intersecting value of
A
and
B
in the table (see triangle).
2. Find temperature drop across coil
Measure the coil’s dry bulb
entering and leaving air temperatures (
A
and
C
). Temperature Drop
Formula: (
T
Drop
) =
A
minus
C
.
3. Determine if fan needs adjustment
If the difference between
the measured
T
Drop
and the desired
D
T
(T
Drop
–
D
T)
is 3º, no
adjustment is needed. See examples: Assume
D
T
= 15 and
A
temp.
= 72º, these
C
temperatures would necessitate stated actions:
Cº T
Drop
–
D
T
=
ºF
ACTION
53º
19
–
15
=
4
Increase the airflow
58º
14
–
15
=
−1
(3º range) no change
62º
10
–
15
=
−5
Decrease the airflow
4. Adjust the fan speed
See indoor unit instructions to increase/
decrease fan speed.
Changing air flow affects all temperatures; recheck temperatures to
confirm that the temperature drop and
D
T are 3º.
D
T
80
24 24 24 23 23 22 22 22 20 19 18 17 16 15
78
23 23 23 22 22 21 21 20 19 18 17 16 15 14
76
22 22 22 21 21 20 19 19 18 17 16 15 14 13
74
21 21 21 20 19 19 18 17 16 16 15 14 13 12
72
20 20 19 18 17 17 16 15 15 14 13 12 11 10
70
19 19 18 18 17 17 16 15 15 14 13 12 11 10
57 58 59 60 61 62 63 64 65 66 67 68 69 70
Temp.
of air
entering
indoor
coil ºF
INDOOR
COIL
DRY
BULB
DRY
BULB
WET
BULB
B
T
Drop
19º
A
Dry−bulb
Wet−bulb ºF
A
72º
B
64º
C
53º
air flow
air flow
All temperatures are
expressed in ºF
Figure 27. Checking Indoor Coil Airflow Guide
