Daikin DSG SERIES, Руководство по установке, Страница: 21 / 60

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condition, the superheat should range from 9°F to 11°F for
each refrigeration circuit measured at the suction service
port located near the compressor.
s
tart
-u
P
P
rOcedure and
c
hecklist
Begin with power turned off at all disconnects.
1. Turn thermostat system switch to “Cool,” and fan switch to
“Auto” and turn temperature setting as high as it will go.
2. Inspect all registers and set them to the normal open position.
3. Turn on the electrical supply at the disconnect.
4. Turn the fan switch to the “ON” position. The blower
should operate after a 7 second delay.
5. Turn the fan switch to “Auto” position. The blower should
stop after a 65 second delay.
6. Slowly lower the cooling temperature until the unit starts.
The compressor, blower and fan should now be operat-
ing. Allow the unit to run 10 minutes, make sure cool air is
being supplied by the unit.
After the 10 minute run, continue lowering cooling tem-
perature until blower speed increases indicating 2nd
stage cooling. Make sure cool air is still being supplied
by unit and proceed to step 7.
7. Turn the temperature setting to the highest position, stop-
ping the unit. The indoor blower will continue to run for 65
seconds.
8. Turn the thermostat system switch to “OFF” and discon-
nect all power when servicing the unit.
r
efrigeratiOn
s
equence
c
heck
With the disconnect switch open, remove the field connect -
ed thermostat wire from terminal R on TB1 terminal block.
Place a jumper across terminals R and G, and across R and
Y on TB1 terminal block. Close the disconnect switch. The
following operational sequence should be observed.
1. Current through primary winding of transformer TRANS1
energizes the 24-volt control circuit.
2. To simulate a mechanical call for cooling from the wall
thermostat, place a jumper across terminals R and Y of
terminal block TB1. The cooling is energized when the
room temperature is above the thermostat set-point for
cooling. The thermostat makes R to Y.
3. UNIT WITH ECONOMIZER OPTION: The compressor
circuit is interlocked through terminals 1 and 4 of the
economizer module. If the outdoor air enthalpy (tempera-
ture and humidity) is not suitable for cooling, the econo-
mizer terminals will be closed permitting compressor to
be energized.
4. The belt drive blower contactor closes its contacts L1, L2
and L3 to T1, T2 and T3 to provide power to the supply
fan motor.
PSC Motor
Adjust the CFM for the unit by changing the speed tap of
the indoor blower motor at the EBTDR “com” connection
with one of the speed taps on “M1” or “M2”. (Black-High
Speed, Blue-Medium Speed, Red-Low Speed.)
EEM Motor
Adjust the CFM for the unit by changing the position of
the low voltage leads on the motor terminal block. White
is for fan only and gas heat, Yellow is for cooling. Refer
to Appendix A for blower performance at each speed tap.
NOTE: If more than one lead is energized simultaneous-
ly, the motor will run at the higher speed.
5. Check supply fan rotation. If the supply fan is rotating in
the wrong direction, disconnect and lock off Single Point
Power Block. Do not attempt to change load side wiring.
Internal wiring is set at the factory to assure that the sup-
ply fan and compressors all rotate in the proper direction.
Verification of correct supply fan rotation at initial startup
will also indicate correct compressor rotation. Reconnect
power and check for proper operation.
6. Compressor contactor closes its contacts L1, L2 and L3
to T1, T2 and T3 to provide power to the compressor mo-
tor COMP. 1. In addition, contactor C1 closes its contact
L3 to T3 , energizing the condenser fan motor.
BURN HAZARD!
DO NOT TOUCH! DISCHARGE LINE MAY BE HOT!
WARNING
7. Check that the compressor is operating correctly. The scroll
compressors in these units MUST operate in the proper ro-
tation. To ensure the compressors are operating in the cor-
rect direction, check the compressor discharge line pres-
sure or temperature after the compressor is started.
The discharge pressure and discharge line tempera-
ture should increase. If this does not occur and the
compressor is producing an exceptional amount of
noise, perform the following checks.
• Ensure all compressors and the supply fan motor
are operating in the proper direction. If a single mo-
tor is operating backwards, check the power wiring for
that motor and correct any leads that have been inter-
changed at the contactor or at the motor.
• If all of the motors are operating backward, discon-
nect the unit power supply and lock it in the “OFF”
position. Switch two leads of the power supply at the
unit Single Point Power Block. Reconnect power and
check for compressor and supply fan motor operation.
8. With all safety devices closed, the system will contin-
ue cooling operation until the thermostat is satisfied.
9. Disconnecting the jumper wire between R and Y and
between R and G on TB1 terminal block will simulate
a satisfied thermostat. The compressor will cycle off
and IIC (pin 12) will initiate its time delay cycle. The
compressor and the supply fan will cycle off.
10. After a time delay of approximately 3 minutes, the
compressor control circuits will be ready to respond to
a subsequent call for cooling from the wall thermostat.
11. Open disconnect switch. Reconnect the field thermo -
stat wire at terminal R on terminal block TB1.