Hitecsa CLOSE CONTROL CED Série Mode D'emploi page 36

I N S T A L L A T I O N
As the operation continues, check the manometers (high and low pressure) as well as the
liquid sight glass, shutting temporarily the cylinder.
Depending on the type of condenser control that has been fitted, condensing pressure during operation can result more or
less stable:
When a MODULATING condenser control (config. 2 - 4) has been fitted, the pressure will be stable at a value of
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about 16 bar (R22 and R407c) or 10 bar (R134a).
When an ON - OFF condenser control (config. 2 - 4) has been fitted, the pressure will rise to 16 bar and then
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decrease more or less rapidly depending on the temperature of the air.
- When a pressure valve has been fitted to control condensing pressure (config. 1 - 3) for use with well-water, the
pressure valve must be adjusted as indicated in Figure 9; if cooling-tower water is used in a closed circuit, the
installation must foresee a temperature control of the water coming to the condenser.
If the condensing pressure exceeds 19 bar (R22 and R07c) or 10 bar (R134a), stop the compressor and check the
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condenser which will almost certainly be insufficiently cooled.
In the case of high condensing temperature with water-cooled condensers, check the temperature of the water
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entering and exiting the condenser and if necessary, adjust the water flow valve.
- The suction pressure will vary in parallel with the supply pressure.
During the period that the circuit is not fully loaded, one can notice:
•
Through the sight glass one will be able to see a bubbling opaque white liquid rushing quickly past.
•
The direct expansion coil will be cold only in the portion near the distributor pipes which could even be
frozen (frosted) whereas the return pipes to the compressor are not cold yet.
As the loading process continues the liquid seen through the sight glass will become clearer and will fill up with refrigerant in
its liquid state:
- Stop the compressor
Shut the cylinder and check that the manometer on the suction line indicates a pressure greater than 4 bar (R22 and
-
R407c) or 1 bar (R134a).
Restart the compressor.
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Continue the loading process until through the sight glass one sees only very few small bubbles of Freon gas.
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At this point the system is fully loaded with gas and the cylinder can be removed leaving, however, the manometers
connected to check that the evaporating and condensing pressures are as per design pressures.
Example (configuration 2):
Air entering evaporator +24°C.
Evaporating temperature +5°C.
Air entering evaporator +22°C.
Evaporating temperature +4°C.
Air entering condenser +20°C
Condensing temperature +38°C.*
Air entering condenser +25°C
Condensing temperature +43°C.*
Air entering condenser +30°C
Condensing temperature +48°C.*
Air entering condenser +32°C
Condensing temperature +50°C.*
Air entering condenser +35°C
Condensing temperature +52°C.*
05.08 Ref.200989 Rev.100 37