Table of Contents
Advertisement
Figure 98: Typical Unit Ventilator/Condensing Unit Wiring Diagram
Typical Unit Ventilator Interface
24V
Rec3
3
2
T4
1
To controls by others, to energize condensing unit normally
open contact.
WARNING
Hazardous Voltage! Disconnect all electric power including
remote disconnects before servicing. Failure to disconnect power
before servicing can cause severe personal injury or death.
Determining System Superheat
After the subcooling has been determined, check system
superheat.
Determine required superheat from superheat range,
1 .
Table
33.
Measure suction line temperature 6 inches from
2 .
service valve.
Measure suction line pressure at service valve and
3 .
determine saturated suction temperature from
Subtract saturated suction temperature from
4 .
measured temperature to obtain superheat.
Refer to
Table 33
and adjust charge as required for
5 .
correct superheat at ambient conditions.
NOTICE
Each time that charge is added or removed from the system, allow
the system to run approximately 20 - 30 minutes before pressure
and temperature readings are taken and superheat calculations
made.
NOTICE
If system hunting occurs or subcooling is reduced, it may be
necessary to adjust TXV to obtain correct superheat.
www.DaikinApplied.com
Head
Pressure
Controller
(Optional)
High
Pressure
Switch
Low
Pressure
Switch
Low Ambient
Temp. Switch
TDR or TB
24V
TDR = Time Delay Relay
TB = Terminal Block
Table
32.
39
Typical Condensing Unit
Capacitor
T
T
2
1
Compressor
Contactor
L
L
1
2
Line Voltage
L
2
L
1
Factory Wired
Field Wired (By Others)
Table 32: Saturated Temperature - Pressure Chart
(ºF)
R410A-PSIG
(ºF)
32
101.1
44
33
103.2
45
34
105.2
46
35
107.4
47
36
109.5
48
37
111.7
49
38
113.9
50
39
116.2
55
40
118.4
60
41
120.7
65
42
123.0
70
43
125.4
75
Table 33: Superheat Range
Indoor Coil Air Inlet Temp . DB/WB (50% RH)
Outdoor
Ambient
75/63
105
*
100
*
95
*
90
*
85
5-7
80
8-10
75
10-12
70
13-15
65
15-17
Fan
Motor
Compressor
R410A-PSIG
(ºF)
R410A-PSIG
127.7
80
235.8
130.2
85
254.7
132.6
90
274.5
135.1
95
295.5
137.5
100
317.6
140.1
105
340.9
142.6
110
365.4
147.0
115
391.2
170.1
120
418.3
185.2
125
446.9
201.1
130
476.8
218.0
140
541.4
80/67
85/71
*
8-10
3-5
9-11
5-7
11-13
9-11
13-15
10-12
15-17
12-14
18-20
15-17
21-23
19-21
24-26
21-23
26-28
IM 817-7
Hide quick links:
Advertisement
Table of Contents
