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Provide personal protection equipment including safety
glasses and/or a face mask, waterproof clothing and
safety gloves. It is recommended to wear clothing that
covers the whole body.
-
Start the high-pressure spray gun and remove any soap
or industrial cleaner from it before cleaning the condenser
coils. Only drinkable cleaning water is permitted to clean
the condenser coils.
-
Clean the condenser face by spraying the coil evenly und
in a stable manner from bottom to top, directing the water
jet at right angles to the coil. Do not exceed 6200 kPa (62
bar) or an angle of 45° related to the coil. The diffuser
must be at least 300 mm away from the coil surface. It is
essential to control the pressure and to be careful not to
damage the fins.
ATTENTION: Excessive water pressure can break the weld
points between the fins and the flat MCHE microchannel
tubes.
13.6.2 - Level 2
Clean the coil, using appropriate products. We recommend
cleaning with clear water to remove pollutants. If the use of
cleaning products is necessary, we specify:
-
pH between 7 and 8
-
Absence of chlorine, sulphate, copper, iron, nickel or
titanium
-
Chemical compatibility with aluminium and copper.
For RTPF coils this process can either be carried out using a high-
pressure spray gun in the low-pressure position. With pressurised
cleaning methods care should be taken not to damage the coil
fins.
The spraying of the coil must be done:
-
In the direction of the fins
-
In the opposite direction of the air flow direction
-
With a large diffuser (25-30°)
-
At a minimum distance of 300 mm from the coil.
It is not necessary to rinse the coil, as the products used are pH
neutral. To ensure that the coil is perfectly clean, we recommend
rinsing with a low water flow rate.
For MCHE condenser coils refer to chapter 13.6.1.2 under level
1 maintenance for use of a high-presssure spray gun.
IMPORTANT:
-
Never use pressurised water without a large diffuser.
Do not use high-pressure cleaners for Cu/Cu and Cu/
Al coils! High pressure cleaners are only permitted
for MCHE coils (maximum permitted pressure 6200
kPa (62 bar).
-
Concentrated and/or rotating water jets are strictly
forbidden.
-
Never use a fluid with a temperature above 45 °C to
clean the air heat exchangers.
-
Correct and frequent cleaning (approximately every
three months) will prevent 2/3 of the corrosion
problems.
-
Protect the control box during cleaning operations.
13.7 - Evaporator maintenance
Check that:
-
The insulating foam is intact and securely in place.
-
The cooler heaters are operating, secure and correctly
positioned.
-
The water-side connections are clean and show no sign
of leakage.
13.8 - Compressor maintenance
13.8.1 - Oil separator
Check the correct operation of the heaters and check that they
are well attached to the oil separator ring.
13.8.2 - Integral oil filter change
As system cleanliness is critical to reliable system operation, there
is a filter in the oil line at the oil separator outlet. The oil filter is
specified to provide a high level of filtration (5 µm) required for long
bearing life.
The filter should be checked after the first 500 hours of operation,
and every subsequent 2000 hours. The filter should be replaced at
any time when the pressure differential across the filter exceeds
200 kPa (2 bar).
The pressure drop across the filter can be determined by
measuring the pressure at the filter service port and the oil pressure
port. The difference in these two pressures will be the pressure
drop across the filter, check valve, and solenoid valve. The pressure
drop across the check valve and solenoid valve is approximately
40 kPa (0.4 bar), which should be subtracted from the two oil
pressure measurements to give the oil filter pressure drop.
13.8.3 - Compressor rotation control
Correct compressor rotation is one of the most critical appli-cation
considerations. Reverse rotation, even for a very short duration,
damages the compressor.
The reverse rotation protection scheme must be able to determine
the direction of rotation and stop the compressor within 300 ms.
Reverse rotation is most likely to occur when-ever the wiring to the
compressor terminals is disturbed.
To minimize the opportunity for reverse rotation, the follow-ing
procedure must be applied. Rewire the power cables to the
compressor terminal pin as originally wired.
For replacement of the compressor, a low pressure switch is
included with the compressor. This low pressure switch should be
temporarily installed as a hard safety on the high pressure part of
the compressor. The purpose of this switch is to protect the
compressor against any wiring errors at the compressor terminal
pin. The electrical contact of the switch would be wired in series
with the high pressure switch. The switch will remain in place until
the compressor has been started and direction of rotation has
been verified; at this point, the switch will be removed.
The switch that has been selected for detecting reverse rotation
is Carrier part number HK01CB001. This switch opens the contacts
when the pressure falls below 7 kPa. The switch is a manual reset
type that can be reset after the pressure has once again risen
above 70 kPa. It is critical that the switch be a manual reset type
to preclude the compressor from short cycling in the reverse
direction.
13 - STANDARD MAINTENANCE
Summary of Contents for AquaForce 30XB series
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