CLIVET WSA-XEE 182, Installation And Operating Manual

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M02S40N16-00 WSA-XEE 122-402 27
6.14 Evaporator water flow-rate
Check that the difference between the temperature of exchanger return and supply water corresponds to power according to this formula:
unit cooling power (kW) x 860 = Dt (°C) x flow rate (L/h)
The cooling power is shown in the table of the GENERAL TECHNICAL DATA included in this manual, referred to specific conditions, or in the
tables on COOLING PERFORMANCE in the TECHNICAL BULLETIN referred to various conditions of use.
Check for water side exchanger pressure drops:
determine the water flow rate
measure the difference in pressure between exchanger input and output and compare it with the graph on WATER SIDE EXCHANGER
PRESSURE DROPS
The measurement of pressure will be easier if pressure gauges are installed as indicated in the DIAGRAM OF SUGGESTED WATER CONNECTIONS.
6.15 Operating at reduced load
The units are equipped with partialization steps and they can, therefore, operate with reduced loads.
However a constant and long operation with reduced load with frequent stop and start-up of the compressor/s can cause serious damages
for the lack of oil return.
The above-described operating conditions must be considered outside the operating limits.
In the event of compressor breakdown, due to operating in the above-mentioned conditions, the guarantee will not be valid and Clivet spa
declines any responsibility.
Check periodically the average operating times and the frequency of the compressors starts: approximately the minimum thermal load
should be such as to need the operating of a compressor for at least ten minutes.
If the average times are close to this limit, take the proper corrective actions.
6.16 Scroll compressor
The Scroll compressors have only one rotation direction.
In the event it is reversed, the compressor is not immediately damaged, but increases its noise and jeopardises pumping.
After a few minutes, the compressor blocks due to intervention of the thermal protection.
In this case, disconnect power supply and invert 2 phases on the machine power supply.
Avoid the compressor working for a long time with contrary rotation: more than 2-3 of these anomalous start-ups can damage it.
To ensure the rotation direction is correct, measure the condensation and suction pressure.
The pressures must significantly differ: upon start-up, the suction pressure decreases whereas the condensation one, increases.
6.17 Start-up report
Identifying the operating objective conditions is useful to control the unit over time.
With unit at steady state, i.e. in stable and close-to-work conditions, identify the following data:
•
total voltages and absorptions with unit at full load
•
absorptions of the different electric loads (compressors, fans, pumps etc)
•
temperatures and flows of the different fluids (water, air) both in input and in output from the unit
•
temperature and pressures on the characteristic points of the refrigerating circuit (compressor discharge, liquid, intake)
The measurements must be kept and made available during maintenance interventions.
6.18 97/23 CE PED directive
97/23 CE PED DIRECTIVE gives instructions for installers, users and maintenance technicians as well.
Refer to local regulations; briefly and as an example, see the following:
Compulsory verification of the first installation:
•
only for units assembled on the installer’s building site (for ex. Condensing c direct expansion unit)
Certification of setting in service:
•
for all the units
Periodical verifications:
•
to be executed with the frequency indicated by the Manufacturer (see the “maintenance inspections” paragraph)