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Installation and User’s Guide
Problem or Symptoms
Possible Cause
Corrective Action
Higher than Normal Head Pressure, lower than
normal suction pressure with high superheat
and very cold or frosty distributor tubes,
may
have no Alarm.
TXV stuck closed.
1. Disconnect TXV bulb from suction line (SL), have it in your hand, if
pressures go back to normal, then reinstall the bulb on suction line (it
may have some debris stuck in the port). For adjustable TXVs open
adjustable valve, it may remove the debris and set it back to original
position.
2. If (1) does not work, recover the charge, remove bulb from SL,
unscrew TXV head, shake it, if rattles, replace head
(PN KT-45-ZGA), if not, replace TXV and filter dryer and charge
appropriately.
Lower than Normal Head Pressure, higher
than normal suction pressure with cold suction
line and compressor and no superheat,
may
have no Alarm.
TXV stuck open.
1. Check to see if TXV bulb is firmly attached to suction line, if loose,
attach firmly by tightening the clamp over the bulb and suction line.
2. If (1) above does not work, reclaim charge and replace TXV and
filter dryer with nameplate charge.
Unusually higher than normal current.
TXV stuck closed/partially closed, insufficient water
flow, system overcharged.
See Possible Cause column for:
TXV stuck closed
,
Insufficient
water flow
, and
Unit overcharged
.
Low current with high superheat.
Unit undercharged.
Find source of refrigerant leak and fix. Pull vacuum and charge.
Unit runs, but trips continously.
Wires not connected properly.
Fix the miswire as per the Wiring Diagrams.
Problem or Symptoms
Possible Cause
Corrective Action
Incorrect Wiring.
Check the Light on Phase Monitor inside the electrical box. If red,
switch two of the Input wires. Any two of the three can be switched.
Faulty Phase Monitor.
Call dealer or factory for advice before attempting to replace parts.
Replace Phase Monitor.
Loose wire on Phase Monitor, either from the supply
input power or the output side.
Check the Light on Phase Monitor inside the electrical box. If the Light
is Red, fix the supply power loose end. If the Light is Green, fix the
output loose wire.
Compressor making a loud or unusual noise or
sounds during operation. Fan is turning, no
cool air discharge out of top of heater. Unit
ON, and Set Temperature is above Actual, but
Unit is not heating.
Compressor running Backwards. This usually
happens if the compressor wire harness is
disconnected for possible repaire or replacement.
Switch any two of the three wires on the compressor side of the
Contactor.
Problems and Corrective Action (3 Phase Units Only)
Unable to turn Heat Pump ON. Display is
Blank. Unit will NOT start.
°F
OHMS
°F
OHMS
°F
OHMS
°F
OHMS
°F
OHMS
0
85,387
51
19,377
66
13,136
81
9,076
96
6,382
10
62,479
52
18,870
67
12,809
82
8,861
97
6,238
20
46,225
53
18,377
68
12,491
83
8,651
98
6,097
30
34,561
54
17,899
69
12,182
84
8,447
99
5,960
40
26,100
55
17,435
70
11,882
85
8,249
100
5,827
41
25,391
56
16,985
71
11,589
86
8,056
101
5,697
42
24,704
57
16,548
72
11,305
87
7,867
102
5,570
43
24,037
58
16,123
73
11,029
88
7,684
103
5,446
44
23,391
59
15,711
74
10,761
89
7,506
104
5,326
45
22,764
60
15,310
75
10,500
90
7,333
105
5,208
46
22,156
61
14,921
76
10,246
91
7,164
106
5,094
47
21,566
62
14,543
77
9,999
92
6,999
107
4,982
48
20,993
63
14,176
78
9,758
93
6,839
108
4,873
49
20,438
64
13,820
79
9,525
94
6,683
110
4,664
50
19,900
65
13,473
80
9,297
95
6,530
120
3,758
* Temperature Resistance Chart
NOTE: Any service must be done by an authorized service agency person.