Johnson Controls DMS 360 Series, Инструкция по установке, эксплуатации и обслуживанию

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Installation, Operation and Maintenance Manual : 036-1011(0806) Page 22
3. If compressor contactor 1 is not pulled in, check for 24
volts at the coil. If 24 volts are present and contactor is
not pulled in, replace the contactor.
4. Failing the above, if voltage is supplied at compressor
contactor 1, it is pulled in, and the compressor still does
not operate, replace the compressor.
5. If 24 volts is not present at compressor contactor 1, check
for loose wiring between C1 and the compressor
contactor.
6. If 24 volts is not present at the C1 terminal, check for 24
volts from the room thermostat at the UCB Y1 terminal.
If 24 volts is not present from the room thermostat, check
for the following :
• 24 volts at the thermostat Y1 terminal.
• Proper wiring between the room thermostat and the
UCB, i.e. Y1 to Y1, Y2 to Y2,Y3 to Y3 & Y4 to Y4.
• Loose wiring from the room thermostat to the UCB.
7. If 24 volts is present at the UCB Y1 terminal, the
compressor may be out due to an open high pressure
switch, low pressure switch, or freezestat. Check for 24
volts at the HPS1, LPS1, and FS1 terminals of the UCB.
If a switch has opened, there should be a voltage
potential between the UCB terminals, e.g. if LPS1 has
opened, there will be a 24 volt potential between the
LPS1 terminals.
8. If 24 volts is present at the UCB Y1 terminal and none of
the protection switches have opened, the UCB may have
locked out the compressor for repeat trips. The UCB
should be flashing an alarm code. If not, press and
release the ALARMS button on the UCB. The UCB will
flash the last five alarms on the LED. If the compressor
is locked out, cancel any call for cooling. This will reset
any compressor lock outs.
NOTE : While the above step will reset any lockouts,
compressor # 1 may be held off for the ASCD. See the next
step.
9. If 24 volts is present at the UCB Y1 terminal and none of
the switches are open and the compressor is not locked
out, the UCB may have the compressor in an ASCD.
Check the LED for an indication of an ASCD cycle. The
ASCD should time out within 5 minutes. Press and
release the TEST button to reset all ASCDs.
10. If none of the above corrected the error, test the integrity
of the UCB. Disconnect the C1 terminal wire and jumper
it to the Y1 terminal. DO NOT jump the Y1 to C1
terminals. If the compressor engages, the UCB has
faulted.
11. If none of the above correct the error, replace the UCB.
On calls for the second stage of cooling, the supply air blower
motor and compressor # 1 are operating but compressor # 2
is not (the room thermostat fan switch is in the “AUTO”
position).
1. Compressor # 2 will not energize simultaneously with
compressor #1 if a call for both stages of cooling is
received. The UCB delays compressor # 2 by 30
seconds to prevent a power surge. If after the delay
compressor # 2 does not energize on a second stage
call for cooling, check for line voltage at the compressor
contactor 2, and that the contactor is pulled in. Check for
loose wiring between the contactor and the compressor.
2. If compressor contactor 2 is pulled in and voltage is
supplied, lightly touch the compressor housing. If it is
hot, the compressor may be off on inherent protection.
Cancel any calls for cooling and wait for the internal
overload to reset. Test again when cool.
3. If compressor contactor 2 is not pulled in, check for 24
volts at the compressor contactor coil. If 24 volts is
present and compressor contactor is not pulled in,
replace the contactor.
4. Failing the above, if voltage is supplied at compressor
contactor 2, and it is pulled in, and the compressor still
does not operate, replace the compressor.
5. If 24 volts is not present at compressor contactor 2,
check for 24 volts at the UCB terminal, C2. If 24 volts are
present, check for loose wiring between C2 and the
compressor contactor.
6. If 24 volts is not present at the C2 terminal, check for 24
volts from the room thermostat at the UCB Y2 terminal.
If 24 volts is not present from the room thermostat, check
for the following :
• 24 volts at the thermostat Y2 terminal.
• Proper wiring between the room thermostat and the
UCB, i.e. Y1 to Y1, Y2 to Y2, Y3 to Y3 & Y4 to Y4.
• Loose wiring from the room thermostat to the UCB.
7. If 24 volts is present at the UCB Y2 terminal, the
compressor may be out due to an open high pressure
switch, low pressure switch, or freezestat. Check for 24
volts at the HPS2, LPS2, and FS2 terminals of the UCB.
If a switch has opened, there should be a voltage
potential between the UCB terminals, e.g. if LPS2 has
opened, there will be 24 volts of potential between the
LPS2 terminals.
8. If 24 volts is present at the UCB Y2 terminal and none of
the protection switches have opened, the UCB may have
locked out the compressor for repeat trips. The UCB
should be flashing a code. If not, press and release the
ALARMS button on the UCB. The UCB will flash the last
five alarms on the LED. If the compressor is locked out,
remove any call for cooling at the thermostat or by
disconnecting the thermostat wiring at the Y2 UCB
terminal. This will reset any Installation, compressor lock
outs.
NOTE : While the above step will reset any lock outs,
compressor # 1 will be held off for the ASCD, and
compressor # 2 may be held off for a portion of the ASCD.
See the next step.