General Maintenance, Maintenance And Final Recommendations - Carrier 61AF Manuel D'installation

61 AF

General maintenance, maintenance and final recommendations

General maintenance
ATTENTION: Before starting any servicing or maintenance operation on
the unit, make sure that the power supply has been disconnected.
A current discharge could cause personal injury.
In order to obtain maximum performance from the unit special
attention should be paid to the following points.
- Electrical connections:
The supply voltage should be within the limits indicated in Table II.
Ensure that no faulty contacts exist in the terminal blocks, contactor
boards, etc.
Make sure that all the electrical connections are properly tightened,
and that all the electrical components (contactors, relays, etc) are
firmly secured to the corresponding rails. Pay special attention to the
condition of the connecting cables between the control elements and
the electrical box, and to that of the unit power supply cable. They
should not be twisted and there should be no slits or notches in the
insulation. Check that the starting and running consumptions are within
the limits specified in Table II.
- Water connections:
Make sure there are no water leaks from the system. Should the unit
be shutdown for long periods, open the drain valve installed on the
hydronic module and partially drain the pump and the water pipes
as well as the drain valve on the plate-type exchanger, which must
be installed on the hydraulic circuit. This operation is essential if
temperatures are expected to drop below freezing. If the unit is not
drained, the main switch should remain connected so that the defrost
thermostat can operate. Carefully clean the system water filter.
- Plate heat exchanger cleaning:
In some applications, for example when very hard water is used, there
is an increased tendency for fouling. In these cases the installation of
a descaling filter is recommended. The heat exchanger can always be
cleaned by circulating a cleaning fluid.
A weak acid solution should be used (5% phosphoric acid or, if
frequently cleaned 5% oxalic acid), and the cleaning fluid should be
pumped through the exchanger. The tank installation can be permanent
or, alternatively, the connections can be prepared and, at any given
time, a portable cleaning device can be connected. To achieve optimum
cleaning the acid solution should be circulated at a minimum of 1.5
times the normal operational flow speed, and preferably in reverse
direction. The installation should then be flushed with large amounts of
water to totally remove the acid before the system is started up.
Tank installation
Cleaning should be done at regular intervals and should never be left
until the unit has become blocked. The time intervals between cleaning
depend on the quality of the water used, but as a general rule it is
advisable to clean it at least once a year.
GB - 12
- Refrigerant circuit:
Ensure that there is no leakage of refrigerant or oil from the compressor.
Check that the high and low side operating pressures are normal. Check
the cleanliness of the refrigerant-water heat exchangers by checking the
pressure drop across them.
- Controls:
Check the operation of all the electrical components, the high
pressurestat and of the high and low pressure transducers and the
water, air and defrost temperature detector.
Maintenance
Servicing recommendations
- Maintenance of the unit must be carried out by skilled personnel
only. Nevertheless, the easiest operations, such as cleaning of the
battery and the unit external parts can be carried out by non-skilled
personnel.
- For any operation on the unit follow thoroughly the instructions
shown in the manual and on the unit labels as well as the Safety
Standards.
Always wear the protective gloves and safety glasses. Pay attention to
burns when brazing.
- Use only Carrier Original Spare Parts when repair is required. Always
make sure the spare parts are installed correctly. Always install the
spare parts in the original position.
- Before replacing any of the elements in the refrigerating circuit,
ensure that the entire refrigerant charge is removed from both the
high and low pressure sides of the unit.
- The control elements of the refrigerating system are highly sensitive. If
they need to be replaced, care should be taken not to overheat them
with blowlamps whilst soldering. A damp cloth should be wrapped
around the component to be soldered, and the flame directed away
from the component body.
- Silver alloy soldering rods should always be used.
- If the total unit gas charge has to be replaced, the quantity should be
as given on the nameplate and the unit should be properly evacuated
beforehand.
- During unit operation all panels should be in place, including the
electrical box access panel.
- If it is necessary to cut the lines of the refrigerant circuit, tube cutters
should always be used and never tools which produce burrs. All
refrigerant circuit tubing should be of copper, specially made for
refrigeration purposes.
Final recommendations
The unit you have purchased has undergone strict quality control
procedures before leaving the factory.
All components, including the control systems and electrical equipment,
etc., are certified by our Quality Control Department, and tested
under the harshest possible operating conditions in our laboratories.
However, after leaving the factory, it is possible that one or more of
these elements may be damaged due to causes beyond our control.
In such an event, the user should not work on any of the internal
components, or subject the unit to operating conditions which are
not specified in this manual, since serious damage may result and the
guarantee would be invalidated. Repair and maintenance work should
always be left to the installer. All recommendations concerning unit
installation are intended as a guideline. The installer should carry out
the installation according to the design conditions and should comply
with all applicable regulations for air conditioning and refrigeration
installations.
NOTE: The manufacturer does not accept responsibility for any
malfunctions resulting from misuse of the equipment.