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11.2 Digital display of main board
11.4 Removing scale
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 70°C.
If there is no effective date, it displays “— —” and indication
point
。
C
A
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
。
C
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.
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 DRS5
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