7.7 Compressor crankcase heaters
Connect the oil resistances on the compressor crankcase at least 8 hours before the compressor is to be starter:
•
at the first unit sta
r
t-up
•
after each prolonged period of inactivity
1.
Supply the resistances switching off the unit isol
a
tor switch.
2.
To make sure that heaters are working, check the power input.
3.
At start-up the compressor crank-case temperature on the lower side must be higher at least of 10°C than the outside
temperature.
Do not start the compressor with the crankcase oil below operating temperature.
7.8 Remote controls
Check that the remote controls (ON-OFF etc) are connected and, if necessary, enabled with the respective parameters as indicated in the
“electrical connections” section.
Check that probes and optional components are connected and enabled with the respective parameters (“electrical connections” section and
following pages).
7.9 Evaporator water flow-rate
Check tha
t the diff
erence 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 fl
w 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 fl
o
w rate
measure the
diff
erence i n pressure between exchanger i nput a nd o utput a nd compare i t w ith t he graph o n WATER S IDE EXCHANGER
PRESSURE DROPS
The measurement of pressure will be easier if pressure gauges are installed as indicated in the DIAGRAM OF SUGGESTED WATER CONNECTIONS.
7.10 Voltages
Check that the air and water temperatures are within in the operating limits.
Start-up the unit.
With unit operating in stable conditions, check:
•
Voltage
•
Total absorption of the unit
•
Absorption of the single electric loads
7.11 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 significa
n
tly diff
er: upon start-up, the suction pressure decreases whereas the condensation one, increases.
7.12 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.
27
Summary of Contents for MSE-XSC3 100.4
Page 1: ...MSE XSC3 90 4 160 4 Installation and operating manual...
Page 3: ...Index of contents 1 4 2 6 3 8 4 10 5 14 6 18 7 26 8 35 9 47 10 52 11 53 12 54 57 3...
Page 19: ...Connections performed by the Customer 19...
Page 50: ...9 15 Compressor replacement 50...
Page 51: ...9 16 Exchanger replacement 51...
