Carrier 24VNA9 Infinity 19VS Installation Instructions Manual page 17

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 5 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 5.
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 5 – Variable Speed Compressor Resistance
(winding resistance at 70_F 20_F)
WINDING
24A
Between
.59
terminals
Between
terminal &
ground
* 24A unit height is 38 ---7/16" and 24B unit height is 31 ---5/8"
CAUTION
!
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.
CAUTION
!
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.
Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.
MODEL 24VNA9 (OHMs)
13, 24B 25 36 37, 48
1.13 .59 .59 .37
>1 mega
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
13, 24B
24A, 25, 36, 37, 48, 49, 60
Status Codes
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.
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.
Utility Interface With Infinity Touch Control
The utility curtailment relay should be wired between the two
49, 60
UTIL connections on the control board for this Infinity
.24
Communicating System (see Fig. 35). This input allows a power
utility device to interrupt compressor operation during peak load
periods. When the utility sends a signal to shut the system down,
the User Interface status screen will display, "Curtailment Yes".
See UI installation instructions for setup details.
17
Fan Motor Resistance
Resistance (Ohms)
21.2
11.1
Time between code
Catalog No: 24VNA9--- 3SI (rev 1)
Replaces: 24VNA9--- 2SI