35
11
UNT-PRC002-GB
Sound power levels
Discharge
Measurement conditions:
Measurements taken in a room adjacent to the room containing the FWD, at the outlet of the rectangular duct (1.5 m
long) fixed to its discharge opening.
Fan
Power level in dB(A), per Hz frequency band
Overall power
Unit
speed
125
250
500
1000
2000
4000
8000
dB(A)
1
55
50
42
37
37
31
30
46
FWD 08
2
57
54
47
40
30
38
40
50
3
58
57
50
42
32
40
43
53
1
57
51
45
42
34
33
28
48
FWD 10
2
58
54
48
45
38
39
35
51
3
60
58
50
48
40
42
39
54
1
57
51
45
42
34
33
28
48
FWD 12
2
58
54
48
45
38
39
35
51
3
60
58
50
48
40
42
39
54
1
56
62
50
48
39
38
36
56
FWD 14
2
61
66
55
53
47
46
45
60
3
63
69
58
56
50
50
49
63
1
57
63
51
49
40
39
37
57
FWD 20
2
61
66
55
53
47
46
45
60
3
63
69
58
56
50
50
49
63
Intake
Measurement conditions:
Measurements taken at the horizontal air intake.
Fan
Power level in dB(A), per Hz frequency band
Overall power
Unit
speed
125
250
500
1000
2000
4000
8000
dB(A)
1
56
55
55
53
46
45
42
57
FWD 08
2
63
62
60
60
53
53
53
64
3
66
65
63
62
56
55
57
67
1
62
58
55
58
51
48
44
61
FWD 10
2
66
63
60
62
56
55
52
66
3
70
67
63
65
59
59
57
69
1
62
58
55
58
51
48
44
61
FWD 12
2
66
63
60
62
56
55
52
66
3
70
67
63
65
59
59
57
69
1
66
65
65
65
57
50
46
68
FWD 14
2
73
72
69
71
64
59
57
74
3
78
76
73
75
69
64
63
78
1
68
72
64
64
56
52
50
69
FWD 20
2
76
76
68
71
65
61
61
75
3
78
79
71
74
69
66
66
78
AH-SVX03C-GB
Frost Protection
Check that the frost protection system is working before the beginning of each winter period. Ensure that the frost
thermostat is working within the correct temperature range.
Condensate drain tank
The cooling coil condensate drain pan and the drain connection should be checked for sediment and deposits and
cleaned as required.
Filters
Use Table 7 as a recommendation for filter cleaning or replacement. Each unit maintenance should be adapted
depending on filter type and on air quality. Filter clogging causes higher air pressure drops resulting in lower air
volume and performance change.
WARNING!
If a damper or intake/discharge hole is positioned on the bottom panel and the section is equipped with
inspection access, safety devices must be provided to cover the damper hole when entering in the section.
Note: It is recommended to install the gauge or the differential pressure switch, if necessary, with a visible indicating
light, to have a constant control over filter cleaning. It is also recommended to adjust the dirty filter setting to the
final air pressure drop indicated in the selection data sheets.
Note: The unit must not be run without filters.
Clean the filter after the first 2 hours of unit operation. The bag and absolute filters must be replaced when filter air
pressure drop reaches the final air pressure drop indicated in the selection datasheets. The washable filters must be
cleaned with air pressure going in the direction opposite the normal air flow and then washed in hot water with the
addition of a small quantity of detergent.
Refer always to filter manufactures cleaning instruction.
The new filters must be installed in the air flow direction as indicated by the arrow on the external frame and as
described in Installation section.
Electrical air heaters
Check the heater for dirt accumulation, the ignition and any build up of corrosion. If required, clean the heating
elements. Check the safety controls and the fan control.
Humidifier/air washer
CAUTION!
The whole humidifier section including the drain pan must be cleaned and disinfected regularly. It must
also be thoroughly cleaned after each operating season.
To optimize the unit life cycle and operation, we strongly recommend the use of a water specialist to verify and
adjust the hardness and quality of the water used in the humidifier systems.
Pumps
The circulating pump and motor maintenance must be carried out in accordance with the manufacturer's
instructions.
As a general rule:
• The pump must never be run dry to avoid any pump damage.
• Ingress of sediment into the pump must be avoided.
• The pump should be run a few minutes every other day to avoid jamming. The installation of an automatic actuator
for this purpose is recommended.
Maintenance
