Commissioning; Preliminary Inspections; First Start-Up Or Restart After Long Inactivity - Trane LIFT 81-P Installation Operation & Maintenance

6 | Commissioning

6. COMMISSIONING
6.1

Preliminary inspections

6.1.1 Electrical
Verify that the voltage on terminals L1, L2 and L3 is that shown on the
plate of the unit (tolerance allowed) ±5%, which can be checked with
a tester. If voltage changes occur frequently, please contact our
technical department to choose suitable protections.
Verify the complete tightness of the fuse holder caps.
Verify that the crankcase heaters (if applicable) are powered correctly:
to check whether the heaters are working properly, check that the
bottom of the compressor is at a temperature of 10 to 15 °C higher
than the ambient temperature.
Power and check the correct direction of rotation for the three-phase
version, which should be clockwise looking at the motor from the fan
side. Otherwise, invert any two of the phase conductors.
6.1.2 Hydraulic
Make sure that the water circuit has been previously cleaned: it is
recommended to wash the water circuit via by-passing the unit and
then check the cleanliness of the system filter.
The machines are shipped with open vents and drains, which must be
closed during installation when filling the water circuit. Labels
indicate their positions.
In models with a hydronic kit, the water drain cap of the pump has
been removed, in order to drain the water contained in it and to
avoid freezing problems during the winter season. The cap is inside
the envelope containing all documents of the unit.
Make sure that the hydraulic system has been bled, thereby
eliminating any residual air. The operation must be performed by
loading gradually and opening the venting devices set up by the
installer in the upper part of the system.
If you are using glycol water you can move the antifreeze set-point.
The value must be equal to the value of the freezing temperature of
the fluid plus 6K.
6.1.3 Cooling
Make sure that the pressure gauges (when present) indicate an
adequate pressure. Pressure gauges can be fitted with shut-off
valves. They should only be opened when necessary and once
readings are taken, they must be closed again.
Check that there is no refrigerant leak, possibly using a leak detector.
6.2

First start-up or restart after long inactivity

6.2.1 Start-up
Activate the machine according to that described in the relative
command section.
6.2.1.1 Checks during operation
Check that the machine does not generate abnormal noise or
excessive vibrations.
20
After a few hours of operation verify that the crown of the liquid and
humidity indicator indicates a dry circuit.
Verify that the machine operates within the optimum working range.
Verify that there is no excessive presence of bubbles in the liquid
indicator. If there are this indicates low refrigerant.
A few minutes after starting the compressors, during the summer
operating cycle, make sure that the condensation temperature is> 5
± 2K with respect to the condenser outlet water temperature and
that the evaporation temperature is 5 ± 2K lower than the
evaporator outlet water temperature.
Verify that the overheating temperature of the refrigerant is between
5 and 7K. To verify:
- Measure the temperature with a contact thermometer
placed on the intake pipe of the condenser .
- Read the temperature indicated on the pressure gauge
connected to the inlet.
- The difference between these temperatures provides the
overheating value.
Verify that the subcooling temperature of the refrigerant is between
4 and 8K. To verify:
- Measure the temperature with a contact thermometer
placed on the outlet pipe from the condenser.
- Read the temperature indicated on a pressure gauge
connected to the liquid outlet of the condenser.
- The difference between these temperatures provides the
subcooling value.
The tests referred to above can be performed using the pressure
gauges supplied with the unit (accessories). Once the checks are
complete, close the shut-off valves of the pressure gauges.
6.2.2 Pump release procedure
Before starting the pump, check that the moving parts rotate freely.
To release the pump:
Remove the fan cover from the seat of the rear motor cover.
Use a screwdriver on the present slot on the motor shaft from the fan
side.
In case of blockage, turn the screwdriver by tapping it lightly with a
hammer.
When the operations are completed, reassemble the components in
reverse order.