Communication And Status Function Lights - Bryant 189BNV EVOLUTION Service Manual

COMMUNICATION AND STATUS FUNCTION LIGHTS

Evolution Connex Control, Green Communications (COMM)
Light
A green LED (COMM light) on the outdoor board (see Fig. 7 and
8) indicates successful communication with the other system
products. The green LED will remain OFF until communication is
established. Once a valid command is received, the green LED will
turn ON continuously. If no communication is received within 2
minutes, the LED will be turned OFF until the next valid
communication. The green LED will be turned off when using a
standard 2- -stage non- -communicating heat pump thermostat.
Amber Status Light
Amber colored STATUS light indicates operation and error status.
See Table 6 for definitions.
S Two minute time delay to return to standby operation from last
valid communication.
Defrost
This user interface (UI) offers 4 possible defrost interval times: 30,
60 and 90 minutes, or AUTO. The default is AUTO.
Defrost interval times: 30, 60, and 90 minutes or AUTO are
selected by the Evolution Connex Control User Interface if using
UI. The 90 minute selection will default to 60 minutes at ambient
below 37 degrees. The UI setting will supersede the dip switch
settings on the control board if not the same.
If using non- -communicating thermostat, defrost intervals are set
using dip switches on outdoor control board (see Fig. 7 and 8).
AUTO defrosts adjusts the defrost interval time based on the last
defrost time as follows:
Fig. 7 – AOC Control Board for 1 and 2 Ton
S When defrost time <5 minutes, the next defrost interval=90
minutes. (outdoor temperature above 37_F)
S When defrost time 5- -7 minutes, the next defrost interval=60
minutes.
When defrost time >7 minutes, the next defrost interval=30
S
minutes.
The control board accumulates compressor run time. As the
accumulated run time approaches the selected defrost interval time,
the control board monitors the coil temperature sensor for a defrost
demand. If a defrost demand exists, a defrost cycle will be initiated
at the end of the selected time interval. A defrost demand exists
when the coil temperature is at or below 32_F (0_C) for 4 minutes
during the interval. If the coil temperature does not reach 32_F
(0_C) within the interval, the interval timer will be reset and start
over.
S Upon initial power up the first defrost interval is defaulted to 30
minutes. Remaining intervals are at selected times.
S Defrost is only allowed to occur below 50_F (10_C) outdoor
ambient temperature.
The defrost cycle is terminated as described below.
S When OAT is > 25_F (+3.89_C), defrost terminates if outdoor
coil temperature (OCT) > 60_F (+15.6_C). And a minimum of
one (1) minute defrost length.
S When OAT ≦ 25_F (+3.89_C), defrost will terminate if OCT is
>45_F (+4.4_C) and a minimum of 2 minutes defrost length.
S Or 10 minutes has passed.
At the defrost termination, the outdoor fan will turn on 10 seconds
before the reversing valve switching.
NOTE: Compressor speed during defrost will go to defrost speed.
A150034
Fig. 8 – AOC Control Board for 3, 4 and 5 Ton
8
A14021