Bryant 288BNV EVOLUTION V Installation Instructions Manual page 20

Suction Thermistor (OST)
Suction Thermistor is used for assisting in EXV control and must
be secured on the suction tube and aligned longitudinally to the
vertical surface of the tube axis (see Fig. 35).
!
UNIT DAMAGE HAZARD
Failure to follow this caution may result in equipment
damage or improper operation.
In order to minimize the ambient influence, make sure the
thermistor curved surface hugs the pipe surface and is
secured tight using the wire tie fished through the original
slot insulating polymer body.
Fig. 35 - - Suction Thermistor (OST) Attachment
(On Suction Tube)
Discharge Thermistor (ODT)
Discharge Thermistor is used for protection against over
temperature of the compressor.
compressor discharge stub- -out (see Fig. 36).
Fig. 36 - Discharge Thermistor (ODT)
Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.
CAUTION
The ODT is located on the
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 6 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 6.
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
as long as none of it has been removed during the cap
removal.
8. Reinstall compressor sound blanket making sure discharge
thermistor and compressor power harness are routed as they
were from the factory
Table 6 – Variable Speed Compressor Resistance
(winding resistance at 70_F 20_F)
WINDING
24A*
A14023
Between
.59
terminals OHM
Between
terminal &
ground
* 24A unit height is 38 ---7/16" and 24B unit height is 31 ---5/8"
!
UNIT DAMAGE HAZARD
Failure to follow this caution may result in equipment damage
and/or improper operation.
Do not use Meggar for measuring the winding resistance.
!
UNIT DAMAGE HAZARD
Failure to follow this caution may result in equipment damage
and/or improper operation.
To maintain water integrity of the compressor fusite terminal
box, the two holes in outer ring need to be full of RTV sealant.
A14024
Fan Motor
If verification of proper operation is required for the fan motor
used in this unit, follow these steps:
1. Disconnect fan motor connector from control board.
2. Measure resistance between any 2 of the 3 leads present.
3. Compare measurement to values below
Unit Size
24B
24A, 25, 36, 48, 60
20
MODEL 288BNV
24B* 25 36 48
1.13 .59 .59 .37
OHM OHM OHM OHM
>1 mega OHM
CAUTION
CAUTION
Fan Motor Resistance
Resistance (Ohms)
21.2
11.1
Catalog No: II288B--- 03
Replaces: II288B--- 02
60
.24
OHM