Bryant 189BNV EVOLUTION, Руководство по обслуживанию

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TROUBLESHOOTING
Service Tool
A150062
Fig. 34 – Service Tool Connection
When working on the outdoor unit of a split system, the technician
would usually need to repeatedly walk between the indoor wall
control and the unit outside. To save time, the communicating
controls offer a service tool feature.
By wiring the service tool into the AOC board and powering it
with an external adapter, the technician can have a wall control
capable of running the system right at the outdoor unit.
To use a service tool, connect the A and B communication bus
wires from this second communicating control to the terminals
marked A and B on the terminal strip located in the bottom left
corner of the AOC board (see Fig. 34). But instead of connecting
the wires on the service tool to the terminals marked C and D,
connect the C and D wires from the service tool to the 24V and C
on ST1 as shown in Fig. 34.
When the service tool is connected and powered up, the
communicating controls inside the home will ”go to sleep” and let
the service tool take control of the system. In this manner, the
service technician can run the diagnostic checkouts right at the
outdoor unit using the service tool.
After the checkouts are completed and it is no longer necessary to
use the service tool, remove it from the communicating controls
and the indoor communicating controls will regain control in about
two minutes.
Systems Communication Failure
If communication is lost with the User Interface (UI), the control
will flash the appropriate fault code (see Table 6). Check the wiring
to the User Interface and the indoor and outdoor units and power.
Model Plug
Each control board contains a model plug. The correct model plug
must be installed for the system to operate properly (see Table 3).
The model plug is used to identify the type and size of unit to the
control.
On new units, the model and serial numbers are inputted into the
AOC board’s memory at the factory. If a model plug is lost or
missing at initial installation, the unit will operate according to the
information input at the factory and the appropriate error code will
flash temporarily. An RCD replacement AOC board contains no
model and serial information. If the factory control board fails, the
model plug must be transferred from the original board to the
replacement board for the unit to operate.
When installing heat pump with older fan coils, a model plug
change may be required.
NOTE : The model plug takes priority over factory model
information input at the factory. If the model plug is removed after
initial power up, the unit will operate according to the last valid
model plug installed, and flash the appropriate fault code
temporarily.
Table 3—Factory Supplied Model Plug Information
288BNV
MODEL PLUG
NUMBER
Pins 1---4 Pins 2---3
13 HK70EZ029 11K 220K
24B HK70EZ009 5.1K 91K
25 HK70EZ001 5.1K 11K
36 HK70EZ002 5.1K 18K
37 HK70EZ026 11K 120K
48 HK70EZ003 5.1K 24K
60 HK70EZ004 5.1K 33K
189BNV
MODEL PLUG
NUMBER
Pins 1---4 Pins 2---3
13 HK70EZ028 11K 180K
24B HK70EZ010 5.1K 120K
25 HK70EZ011 5.1K 150K
36 HK70EZ012 5.1K 180K
37 HK70EZ025 11K 91K
48 HK70EZ013 5.1K 220K
49 HK70EZ027 11K 150K
60 HK70EZ014 5.1K 270K
Status Codes
Unit may occasionally become unresponsive due to certain
combinations of previous fault codes. There may not be
anything wrong with the unit or components. The unit may
require a high voltage power cycling for at least 2 minutes or
longer to clear the condition. If the condition persists, conduct
further troubleshooting per Service Manual.
ATTENTION
!
Table 6 shows the status codes flashed by the amber status light.
Most system problems can be diagnosed by reading the status code
as flashed by the amber status light on the control board.
The codes are flashed by a series of short and long flashes of the
status light. The short flashes indicate the first digit in the status
code, followed by long flashes indicating the second digit of the
error code.
The short flash is 0.25 seconds ON and the long flash is 1.0 second
ON. Time between flashes is 0.25 seconds. Time between short
flash and first long flash is 1.0 second. Time between code
repeating is 2.5 seconds with LED OFF.
Codes are easily read from user interface (UI)
EXAMPLE :
3 short flashes followed by 2 long flashes indicates a 32 code.
Table 6 shows this to be low pressure switch open.
Variable Speed Compressor Winding Resistance
This compressor operates with 3--phase variable frequency PWM
variable voltage. For troubleshooting certain fault codes related to
compressor resistances, follow these steps:
1. Disconnect compressor power leads from the inverter MOC
terminals, U (YEL), V (RED), and W (BLK).
2. Measure the resistance between YEL to RED, YEL to BLK,
and RED to BLK and compare to Table 4 values. Each
resistance set should be equal.
3. Measure the resistance to ground for each lead.
4. If the resistances check out, reconnect power leads to
appropriate terminal.
5. If the resistances appear to be abnormal, it will be necessary
to measure the resistance at the compressor fusite terminals.
6. During the removal of the compressor fusite cap, do not re-
move the RTV sealant. Remove the harness plug, measure
the resistances, and compare to Table 4.
7. Special care will need to be taken with the replacement of
the compressor fusite cap. Make sure the two holes in the
compressor fusite terminal box are still full of RTV sealant
before the cap is reinstalled. The factory RTV can be reused