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9 - SYSTEM START-UP
The belts have only been pretensioned for storage and shipping purposes. It is essential to tension them using the procedure described
below:
Deflection test:
The belt tension must be checked and corrected using a suitable measuring instrument (tensiometer or dynamometer).
Ea calculation:
- Ea = (e x E)/100 = Deformation in mm for a pulley centre distance of 100 mm
- e = Pulley centre distance in mm
- E = See table below for the value
- f = Force applied
At the centre of the centre distance "e", apply a force "f" to each belt, as determined in the table below.
Set the belt tension to obtain the calculated deflection Ea.
Load to be applied
Belt type
SPZ
SPA
SPB
SPC
During commissioning, the belt tension must be checked after 48 hours of operation.
9.5 - Heating and Cooling coil
■ Take all necessary measures to prevent the water in the coils from freezing during operation or when the air handling unit is powered
off.
- Install thermostats and/or safety pressostats.
- Glycol protection: Metering should be based on the temperature (see table below).
- This gives the minimum glycol concentrations based on the freezing point:
Concentration
Ethylene glycol
Propylene glycol
Other products are available. Refer to the manual provided by the antifreeze supplier.
■ If you use a concentrated dilutable solution to protect your hydraulic circuit, please follow the instructions below:
- Never add pure antifreeze product followed by water,
- Always prepare the correctly metered water + antifreeze + corrosion inhibitor mixture in a container before adding it to the system,
- Add the water/antifreeze/inhibitor and pressurise using a hydraulic pump,
- Circulate the mixture throughout the system for at least 2 hours before starting up the unit,
- Check the final metering obtained with a density meter or a refractometer,
- Check the pH obtained using strips of pH paper or a pH-meter (see water quality table below),
- Affix, in a visible location, a label stating:
• That the system contains antifreeze,
• The name of the product and the supplier,
• The metering and pH at system start-up.
■ If a top-up is required, it must be done using a mixture identical to that originally used. Same products, same metering, same
procedure.
■ During complete or partial draining, the water or coolant must not be drained directly to the sewer or the rainwater network. Consult
the regulations in force at the installation site.
■ Do not exceed the permissible pressure and temperature values. Refer to the unit's technical specifications.
■ The water or antifreeze mixture circulating in the heat exchangers must be filtered and must not contain any impurities, to prevent
fouling. The performance of a fouled heat exchanger will be severely reduced.
■ The water or antifreeze mixture must be correctly treated to prevent corrosion or attacks on the materials used.
per belt
f (N)
25
50
75
125
%
0
°C
0
°C
0
Small pulley diameter
mm
56 ≤ 71
< 71 ≤ 90
< 90 ≤ 125
125
71 ≤ 100
< 100 ≤ 140
< 140 ≤ 200
200
112 ≤ 160
< 160 ≤ 224
< 224 ≤ 355
355
180 ≤ 250
< 250 ≤ 355
< 355 ≤ 560
560
10
20
-3
-7
-4
-8
Belt deformation for a pulley centre distance of
100 mm - E (mm)
2,45
2,20
2,05
1,90
3,20
2,75
2,55
2,45
3,00
2,55
2,22
2,10
2,55
2,20
2,00
1,90
30
40
-14
-24
-12
-20
f
e
50
-35
-33
53
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