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11.2 Digital display of main board
The data display area is divided into Up area and Down area,
with two groups of two-digit half 7-segment digital display,
respectively.
a. Temperature display
Temperature display is used for displaying the total outlet water
temperature of unit system, outlet water temperature ,condenser
pipe temperature T3A of system A, condenser pipe temperature
T3B of system B, outdoor environmental temperature T4, anti-
freezing temperature T6 and setting temperature Ts, with
allowable data display scope -15°C~70°C. If the temperature is
higher than 70°C, it is displayed as 70C. If there is no effective
date, it displays “— —” and indication point °C
°C
is on.
b. Current display
Current display is used for displaying Modular unit system A
compressor current IA or system B compressor current IB, with
allowable display scope 0A~99A. If it is higher than 99A, it is
displayed as 99A. If there is no effective date, it displays “— —”
and indication point A
A
is on.
c. Failure display
It is used for displaying the total failure warning date of unit
or that of Modular unit, with failure display scope E0~EF, E
indicating failure, 0~F indicating failure code. “E-“ is displayed
when there is no failure and indication point #
#
is on at the same
time.
d. Protection display
It is used for displaying the total system protection data of unit
or the system protection data of Modular unit, with protection
display scope P0~PF, P indicating system protection, 0~F
indicating protection code. “P-“ is displayed when there is no
failure .
e. Unit number display
It is used for displaying the address number of the currently
selected Modular unit, with display scope 0~15 and indication
point #
#
is on at the same time.
f. Display of online unit number and startup unit number
They are used for displaying the total online Modular units of
the whole unit system and the number of the Modular unit under
running state, respectively, with display scope 0~16.
Any time when the spot check page is entered to display or
change Modular unit, it is needed to wait for the up-to-date data
of the Modular unit received and selected by wired controller.
Before receiving the data, the wired controller only displays “— — ” on
the data display Down area, and the Up area displays the address
number of the Modular unit. No page can be turned, which
continues until the wired controller receives the communication
data of this Modular unit.
11.3 Care and maintenance
1) Maintenance period
It's recommended that before cooling in summer and
heating in winter every year, consult local air conditioner
customer service center to check and maintain the unit, to
prevent air conditioner errors which bring inconvenience to
your life and work.
2) Maintenance of main parts
Close attention should be paid to the discharge and
suction pressure during the running process. Find
out reasons and eliminate the failure if abnormality is
found.
Control and protect the equipment. See to it that no
random adjustment be made on the set points on site.
Regularly check whether the electric connection is loose,
and whether there is bad contact at the contact point
caused by oxidation and debris etc., and take timely
measures if necessary.
Frequently check the work voltage, current and phase
balance.
Check the reliability of the electric elements in time.
Ineffective and unreliable elements should be replaced in
time.
11.4 Removing scale
After long-time operation, calcium oxide or other minerals
will be settled in the heat transfer surface of the water-
side heat exchanger. These substances will affect the
heat transfer performance when there is too much scale
in the heat transfer surface.
and sequentially cause that electricity consumption
increases and the discharge pressure is too high (or
suction pressure too low). Organic acids such as formic
acid, citric acid and acetic acid may be used to clean the
scale. But in no way should cleaning agent containing
fluoroacetic acid or fluoride should be used as the water-
side heat exchange is made from stainless steel and
is easy to be eroded to cause refrigerant leakage. Pay
attention to the following aspects during the cleaning and
scale-removing process:
1) Water-side heat exchanger should be done be
professionals. Please contact the local air-conditioner
customer service center.
2) Clean the pipe and heat exchanger with clean water
after cleaning agent is used. Conduct water treatment to
prevent water system from being eroded or re-absorption
of scale.
3) In case of using cleaning agent, adjust the density of
the agent, cleaning time and temperature according to the
scale settlement condition.
4) After pickling is completed, neutralization treatment
needs to be done on the waste liquid. Contact relevant
company for treating the treated waste liquid.
5)
Protection equipments (such as goggles, gloves,
mask and shoes) must be used during the cleaning process
to avoid breathing in or contacting the agent as the cleaning
agent and neutralization agent is corrosive to eyes, skins and
nasal mucosa.
11.5 Winter shutdown
For shutdown in winter, the surface of the unit outside
and inside should be cleaned and dried. Cover the unit
to prevent dust. Open discharge water valve to discharge
the stored water in the clean water system to prevent
freezing accident (it is preferable to inject antifreezer in
the pipe).
11.6 Replacing parts
Parts to be replaced should be the ones provided by our
company.
Never replace any part with different part.
Summary of Contents for KEM-90
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