Carrier 50LC 07, Инструкции по обслуживанию и техническому обслуживанию, Страница: 38 / 100

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Table 7 – Status Code Descriptions for ISC Board LEDs
ERROR# ERROR NAME
LED INDICATION
LED01 LED02 LED03 LED04 LED05
1 Check Smoke Detector/PMR/AUX RED
Blinking
Green
LED
(Note 1)
2 Check HPS/LPS/COFS RED RED
3 Call for Y3 with no call for Y1. Check Y1 wiring. RED
4 Call for Y3 with no call for Y1/Y2. Check Y1 wiring. RED RED
5 Call for Y2 with no call for Y1. Check Y1 wiring. RED RED
6 Call for W2 with no call for W1. Check W1 wiring. RED RED
7 Call for heat (W1/W2) and cooling (Y1/Y2/Y3). Check thermostat wiring. RED RED RED RED
8 Call for heat (W1/W2) with no G. Check G wiring. RED RED RED
9 Call for cooling (Y1/Y2/Y3) with no G. Check G wiring RED RED RED
10
Call for heat (W1/W2) and cooling (Y1/Y2/Y3) with no G.
Check thermostat and G wiring.
RED RED RED
11 Check ISC Board and the thermostat wiring RED RED RED
12 Check ISC Board and the thermostat wiring RED
13 Check ISC Board and the thermostat wiring RED RED
14 Check ISC Board and the thermostat wiring RED
15 Check ISC Board and the thermostat wiring RED RED
NOTES: 1. Green LED Blinking at 1HZ indicates normal operation.
2. Solid red LED indicates an error exists, see above LED configuration.
Cooling —
In the Cooling Mode, the small and large compressors will
be sequenced to maintain the thermostat temperature
setpoint. The chart below shows the cooling operation
based on the following conditions.
INPUT OUTPUT
Thermostat
Compressor
C1
Compressor
C2
Indoor
Fan
Speed
Outdoor
Fan
Speed
First Stage Cooling
(Y1)
On Off Low
Low
(700 rpm)
Second Stage Cooling
(Y2)
Off On Medium
Medium
(800 rpm)
Third Stage Cooling
(Y3)
On On High
High
(1000 rpm)
The outdoor fan and VFD controlled indoor--fan will
operate at low, medium and high speed. The RPM is
factory set by the CFM and static pressure requirements
for the unit installed.
Economizer (Optional) —
When the Economizer is in Free Cooling Mode and a
demand for cooling exist (Y1 on the thermostat), the
Economizer will modulate the outdoor--air damper to
provide a 50
_
F (10
_
C) to 55
_
F (13
_
C) mixed--air
temperature into the zone and run the indoor--fan at high
speed. As mixed--air temperature fluctuates above 55 ºF
(13
_
C) or below 50
_
F (10
_
C) dampers will be modulated
(open or close) to bring the mixed--air temperature back
within control. Upon more call for cooling (Y2 on the
thermostat), the outdoor--air damper will maintain its
current position, compressor C1 will run and the
outdoor--fan will run at low speed. If there is further
demand for cooling, the outdoor--air damper will maintain
its current position, compressor C2 will run and the
outdoor--fan will run at medium speed. The VFD
controlled indoor--fan will operate at high speed
regardless of the cooling demand.
If the increase in cooling capacity causes the mixed--air
temperature to drop below 45
_
F (7
_
C), the outdoor--air
damper will return to the minimum position. If the
mixed--air temperature continues to fall, the outdoor--air
damper will close. Control returns to normal once the
mixed--air temperature rises above 48
_
F (9
_
C). The
power exhaust fans will be energized and de--energized, if
installed, as the outdoor--air damper opens and closes.
In field--installed accessory CO
2
sensors are connected to
the Economizer, a demand controlled ventilation strategy
will begin to operate. As the CO
2
level in the zone
increases above the CO
2
set--point, the minimum position
of the damper will be increased proportionally. As the
CO
2
level decreases because of the increase of fresh air,
the outdoor--air damper will be proportionally closed. For
economizer operation, there must be a thermostat call for
the fan (G). If the unit is occupied and the fan is on, the
damper will operate at minimum position. Otherwise, the
damper will be closed.
Low Ambient Cooling Operation down to 40
_
F (4
_
C) —
In Low Ambient RTU conditions when the temperature is
between 55
_
F (13
_
C) and 40
_
F (4
_
C), the Low Ambient
Switch (LAS) will be active and the outdoor--fans will run to
the pre--set factory outdoor--fan speed. When the temperature
is greater than 65
_
F (18
_
C), the Low Ambient Switch will
deactivate and the outdoor--fans will run in the standard
cooling mode. If the Outdoor Fan Select Switch (see Fig.
51) is in the up position, the outdoor fans will run in the Fan
Cycle Speed Mode (FCS) set to 250 rpm. If the Outdoor Fan
Select Switch is in the down position, the outdoor fans will
run in the Minimum Fan Speed Mode (MIN) set to 160 rpm
regardless of the cooling demand.
LC Size 07 Units have a SPST normally open Low
Ambient Switch wired across the TS and OF terminal and
a jumper placed across the PS terminal (see Fig. 52).
When the LAS is active, the switch will close making
contact to the OF terminal. This is done for units that