27
Characteristics of R-407C
Relative saturated bubble saturated dew
Relative
saturated bubble saturated dew
Relative saturated bubble saturated dew
pressure point temperature point temperature pressure point temperature point temperature pressure point temperature point temperature
bar
°C
°C bar
°C
°C
bar
°C
°C
1
-28.55
-21.72
10.5
23.74
29.35
20
47.81
52.55
1.25
-25.66
-18.88
10.75
24.54
30.12
20.25
48.32
53.04
1.5
-23.01
-16.29
11
25.32
30.87
20.5
48.83
53.53
1.75
-20.57
-13.88
11.25
26.09
31.62
20.75
49.34
54.01
2
-18.28
-11.65
11.5
26.85
32.35
21
49.84
54.49
2.25
-16.14
-9.55
11.75
27.6
33.08
21.25
50.34
54.96
2.5
-14.12
-7.57
12
28.34
33.79
21.5
50.83
55.43
2.75
-12.21
-5.7
12.25
29.06
34.5
21.75
51.32
55.9
3
-10.4
-3.93
12.5
29.78
35.19
22
51.8
56.36
3.25
-8.67
-2.23
12.75
30.49
35.87
22.25
52.28
56.82
3.5
-7.01
-0.61
13
31.18
36.55
22.5
52.76
57.28
3.75
-5.43
0.93
13.25
31.87
37.21
22.75
53.24
57.73
4
-3.9
2.42
13.5
32.55
37.87
23
53.71
58.18
4.25
-2.44
3.85
13.75
33.22
38.51
23.25
54.17
58.62
4.5
-1.02
5.23
14
33.89
39.16
23.5
54.64
59.07
4.75
0.34
6.57
14.25
34.54
39.79
23.75
55.1
59.5
5
1.66
7.86
14.5
35.19
40.41
24
55.55
59.94
5.25
2.94
9.11
14.75
35.83
41.03
24.25
56.01
60.37
5.5
4.19
10.33
15
36.46
41.64
24.5
56.46
60.8
5.75
5.4
11.5
15.25
37.08
42.24
24.75
56.9
61.22
6
6.57
12.65
15.5
37.7
42.84
25
57.35
61.65
6.25
7.71
13.76
15.75
38.31
43.42
25.25
57.79
62.07
6.5
8.83
14.85
16
38.92
44.01
25.5
58.23
62.48
6.75
9.92
15.91
16.25
39.52
44.58
25.75
58.66
62.9
7
10.98
16.94
16.5
40.11
45.15
26
59.09
63.31
7.25
12.02
17.95
16.75
40.69
45.71
26.25
59.52
63.71
7.5
13.03
18.94
17
41.27
46.27
26.5
59.95
64.12
7.75
14.02
19.9
17.25
41.85
46.82
26.75
60.37
64.52
8
14.99
20.85
17.5
42.41
47.37
27
60.79
64.92
8.25
15.94
21.77
17.75
42.98
47.91
27.25
61.21
65.31
8.5
16.88
22.68
18
43.53
48.44
27.5
61.63
65.71
8.75
17.79
23.57
18.25
44.09
48.97
27.75
62.04
66.1
9
18.69
24.44
18.5
44.63
49.5
28
62.45
66.49
9.25
19.57
25.29
18.75
45.17
50.02
28.25
62.86
66.87
9.5
20.43
26.13
19
45.71
50.53
28.5
63.27
67.26
9.75
21.28
26.96
19.25
46.24
51.04
28.75
63.67
67.64
10
22.12
27.77
19.5
46.77
51.55
29
64.07
68.02
10.25
22.94
28.56
19.75
47.29
52.05
29.25
64.47
68.39
9.4 - Evaporator maintenance
Check that:
•
the insulating foam is intact and securely in place.
•
the sensors are correctly operating, secured and
positioned.
•
the water-side connections are clean and show no sign
of leakage.
9.4.1 - multitube evaporators
To access the evaporator tubes, use the following procedure:
•
Close the chilled water supply and return valves (if
installed), and disconnect the chilled water supply and
return pipe connections.
•
Drain the water from the cooler.
•
Remove all temperature sensors from the cooler.
•
Completely drain the refrigerant charge, using a refri-
gerant recovery unit.
•
Fold back the insulation at the refrigerant line connec-
tions.
•
Remove the header panels from the evaporator.
When the evaporator heads and manifolds are removed, the
outer tube end plates will be visible.
Six or eight evaporator tubes are swaged into the end plate
and cannot be removed. A dot punch mark in the end plate
opposite each one identifies each of them. If any of them
develop a leak, the tube must be plugged, as described below.
9.4.2 - Plugging evaporator tubes
A leaking tube can be plugged pending replacement. The
number of tubes plugged will determine when they should
be replaced. Check with Carrier the effect upon chiller per-
formance of plugging a number of tubes. Carrier will need
to know the number of tubes to be plugged and their posi-
tions. The figure below shows the Elliott method of plugging
tubes.
WARNINg: Take care when inserting plugs not to damage
the plate material between the tubes. Avoid excessive force.
Clean all components with Locquic N and then coat all
surfaces with several drops of Loctite 75 to ensure a good
seal without applying excessive force.
Elliott tube plug
Components
Part number
Tube brass plug
---T-853--103500S-*
Tube brass ring
---T-853--002570S-*
Brass plug (holes without tubes)
---T-853--1031—S-*
Brass ring (holes without tubes)
---T-853--002631S-*
loctite
No. 75
locquic
“N”
* Order directly from your Carrier distributor
Plug
Ring
Tube plate