6.3 Calibration of safety components
Any work on the unit must be carried out by qualified authorised personnel. Incorrect calibration
values can cause serious damage to the unit and harm people.
The control and safety equipment is calibrated and tested in the factory before the unit is shipped.
However, after the unit has been started, the safety devices must be checked (only the high pressure switches).
The checks must be carried out as described in the "Periodic checks" chapter.
The calibration values are shown in the table
Control and safety components
High pressure switch for UATYA25
High pressure switch for 2.1
High pressure switch for all the others
High pressure safety valve (where present)
6.4 Checks during operation
With the circuits operating at 100% and stable at working conditions near the nominal ones, check:
- that the electrical absorption of the unit is close to the data shown in the wiring diagram. Considerably different
values may be due to the reduced capacity operation of the unit, to working conditions very different from the
nominal ones or to the malfunctioning of one or more components.
- that the difference between the condensing temperature of each circuit and that of the air is less than 25°C. If it
is greater, check that all the fans involved are turning correctly and that there are no obstructions or dirt on the
surface of the condensing coil;
- the superheating value of the suction gas: the optimal value is between 4 and 7°C;
- the subcooling value of the liquid leaving the condenser: the optimal value is between 5 and 10°C;
- that the liquid sight glass is green;
- that no bubbles appear on the sight glass placed in the liquid pipe. The continuous presence of bubbles may
indicate a lack of refrigerant charge; the occasional or sporadic presence of bubbles is allowed;
- that the refrigerant filter is not blocked or clogged. To this end, it is sufficient to measure the temperature of the
liquid pipe immediately before and immediately after the filter, and check that there are no significant differences
(up to a couple of degrees C difference is allowed).
- that the condensate drain is working correctly.
Translation from original instructions
Packaged Rooftop
46
Activation set
Differential
point
42,0 barg
42,0 barg
44,0 barg
46 barg
Reset
8,0 barg
Manual
8,0 barg
8,0 barg
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We reserve the right to make changes without any prior notice.
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UATYA
4P645202-1