Maintenance - Trane Flex II Series Installation Operation & Maintenance

14 MAINTENANCE

Maintenance operations are fundamental in order to keep the units running properly, both purely functional and
energetically points of view.
Every Trane unit comes with a logbook, in which the user or the person delegated to machine maintenance can keep all
the required notes, in order to keep a historical log of the Trane unit.
A lack of notes in the logbook could be considered proof of careless maintenance.
14.1 GENERAL
IMPORTANT!
Beyond the cadences of checks recommended in the following, in order to keep the unit at optimum levels of
performance and efficiency and prevent incipient failures, we recommend periodic visits of inspection and control of
the unit by qualified personnel.
In particular, we recommend:
4 annual visits to units that operate about 365 days / year (quarterly)
2 visits per year for units with seasonal operation about 180 days / year (one start seasonal and a mid-season)
1 annual visit for units with seasonal operation of about 90 days / year (starting seasonal)
It's important that during the initial start-up and periodically during operation, carry out the checks and routine checks.
Among them we must also check the suction and condensation as well as the sight glass located on the liquid line.
Check through the microprocessor installed on the unit, the unit is working within normal parameters of superheating
and subcooling. A routine maintenance program recommended is shown at the end of this chapter while a card
collection of operating data is at the end of this manual. It is suggested to record on a weekly basis all the operating
parameters of the unit. The collection of these data will be very useful to technicians, in case it is requested technical
assistance.
Compressor Maintenance IMPORTANT!
This inspection must be performed by qualified and trained personnel.
The analysis of vibration is a great tool for checking the mechanical conditions of the compressor.
It is recommended to check the value of the vibration immediately after starting and periodically on an annual basis.
Compressor Electrical Connections
It is very important that all the compressors are wired correctly for proper rotation. These compressors will not tolerate
reverse rotation. Verify correct rotation/phasing using a rotation meter.
If wired incorrectly the compressor will make excessive noise, will not pump and will draw about half the normal
current. It will also become very hot if allowed to run for an extended period.
NOTICE: Do not "bump" the compressor to check rotation as incorrect rotation could cause compressor motor
failure in as little as 4 to 5 seconds!
Improper rotation of the compressors is indicated by a compressor module trip, noisy operation, no pressure difference
on manifold gauges and low amp draw.
Compressor Replacement
If the chiller suffers a failed compressor, use these steps for replacement:
Each compressor has lifting eyes. Both lifting eyes must be used to lift the failed compressor.
After a mechanical failure of a compressor, it is necessary to change the oil in the remaining compressor and also
replace the liquid line filter drier. After an electrical failure of a compressor, it will also be necessary to change the oil
in the remaining compressor, replace the filters driers and add a suction filter drier with clean-up cores.
Make sure that a heater is correctly installed on the compressor. The heater helps prevent dry starts.
Note: Do not alter the refrigerant piping in any way as this can affect compressor lubrication.
Refrigerant System Open Time
The chillers use POE oil and therefore refrigerant system open time must be kept to a minimum. The following
procedure is recommended:
Leave a new compressor sealed until it is ready to be installed in the unit. Maximum system open time is dependent
upon ambient conditions, but do not exceed one hour open time.
Plug the open refrigerant line to minimize moisture absorption. Always change the liquid line filter drier.
Do not leave POE oil containers open to the atmosphere. Always keep them sealed.
14.2 SIGHT CHECK OF THE LIQUID RECEIVER
The risks due to the pressure inside the circuit have been eliminated or (when it is not possible) reduced by means of
safety devices. It is important to check periodically the status of these devices and to carry out the components
inspections and repositioning as follows.
Check the liquid receivers' state at least once a year.
It is important to check that the surface does not get rusty and that neither corrosion nor deformations are visible.
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