
Installation and Maintenance
Installation and Maintenance
11
8
.
TXV Replacement Information
Please follow the steps below when replacing the TXV:
1.
Disassemble the front panel.
2.
Take the thermal bulb down by undoing the copper strips around it.
3.
Weld the pressure pipe off from the gas pipe with a welding gun. Be careful not to burn the gas pipe.
4.
Weld the TXV off from the liquid pipe with a welding gun. Be careful not to burn the liquid pipe.
5.
Wrap the new TXV with a piece of wet cloth to prevent it from getting overly hot and connect the nitrogen
flow to liquid pipe to prevent it from being oxidized. Weld the TXV to the liquid pipe, and pay attention to
the direction of the TXV, then weld the pressure pipe to the gas pipe.
6.
When the pipe cools down after welding, connect it with 150PSI nitrogen equipment and test and
examine if leakage occurs.
7.
Fix the thermal bulb to the gas pipe with copper strips and perform necessary insulation work.
8.
Evacuate the unit, start up the system, and set the unit to start cooling operation.
9.
When the unit has operated for 20 minutes, adjust the TXV superheat to 6
℉
.
10. When the unit has operated for another 20 minutes, examine whether the superheat is appropriate and
record the figures afterwards.
●: available
: unavailable
╳
NOTE:
The heat kit is an optional
part, and it must
be connected to the power supply separately.
It is recommended that electric heater kit should be installed in low temperature area or when long piping is used.
Check if the heat kit is suitable for AHU 3-way position installation.
Ampacities for MCA and Fuse/breaker including the blower motor.
Heat pump systems require a specified airflow. Each ton of cooling requires between 350 and 450 cubic feet of air
per minute(CFM).
9
.
Electric Heat Kit Selection Table
Electric
Heat Kit
Model
Air
Handler
Model
Electric
Heat
(kW)
2
3
4
5
21-4245-01
24K
5
28.3
25.9
30
30
●
●
●
●
21-4245-02
7.5
40.7
37.2
45
40
╳
●
●
●
21-4245-03
10
53.2
48.5
60
50
╳
╳
●
●
21-4245-01
36K
5
29.8
27.4
30
30
●
●
●
●
21-4245-02
7.5
42.2
38.7
45
40
╳
●
●
●
21-4245-03
10
54.7
49.9
60
50
╳
╳
●
●
21-4245-04
15
42.2+36.9 38.6+33.8
45+40
40+35
╳
╳
╳
●
21-4245-01
48K/60K
5
31.8
29.4
35
30
●
●
●
●
21-4245-02
7.5
44
.
8
40.7
45
45
╳
●
●
●
21-4245-03
10
56.7
51.9
60
55
╳
╳
●
●
21-4245-04
15
44.8+36.9 40.7+33.8
50+40
50+35
╳
╳
●
●
21-4245-05
20
56.7+49.9 51.9+45.2
60+50
60+50
╳
╳
╳
●
MIN. Circuit
Ampacity
230VAC
230VAC
208VAC
208VAC
Fan Speed Tap
MAX. Fuse or Breaker
(HACR) Ampacity