Bryant Legacy 677C**C Series, Руководство по установке

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fan speed and place desired speed tap wire on “HIGH” on
the interface board.
4. Refer to airflow tables (Table 8 or 9) to determine allowable
speeds for the dehumidification cooling fan speed. In Table
8 or 9, speeds that are not allowed for dehumidification
cooling are shaded.
5. Remove the vinyl cap off of the desired speed tap wire
(Refer to Table 6 for color coding) for the dehumidification
cooling fan speed and place desired speed tap wire on the
“LOW” connection on the interface board (IFB). Verify
that static pressure is in the acceptable range for the speed
tap to be used for dehumidification cooling.
6. Use any spare vinyl plugs to cap any unused speed tap
wires.
NOTE : For heat pump operation, the recommended airflow is 350
to 450 CFM for each 12,000 Btuh of rated cooling capacity.
Continuous Fan Speed Set--up (Single Phase Models):
To change continuous fan speed:
1. Remove existing speed tap wire from the “FAN” terminal
on the IGC.
2. Connect the desired speed tap wire on the “FAN” terminal
on the IGC board.
Continuous Fan Operation (3--Phase Models)
When the DEHUM feature is not used, the continuous fan speed
will be the same as cooling fan speed. When the DEHUM feature
is used, the continuous fan will operate on IFB “LOW” speed
when the DH control lead is not energized, or IFB “HIGH” speed
when the DH lead is energized (see Fig. 14).
Table 6 – Color Coding for Indoor Fan Motor Leads
Black = High Speed
Orange = Med---High Speed
Red = Med Speed
Pink = Med---Low Speed
Blue = Low Speed
DH DH
DH DH
DH DH
DH DH
Shunt in no
dehumidification
position
Shunt in
dehumidification
position
A14399
Fig. 13 -- Single Phase IGC Board
COM LOW HIGH
GAS
HEAT
Q1 R1L C8 RL3
Q3
DCR QCR
QC1
G1
G2
A7
D4 D6 C2 OILL
R9 AB A15
C4
C9
C0
R4 RL4
C7
R2
R3 R5 R6
QCB
Y
Y R U C 24VAC
JW1
P2
P1
W2
Y2/ Y1/
Y DH
G C R
SSTZ-8
P3
SDL
24V
AC/R
CDM/C
F1
QC6 QC7 QC4 QC3
K2 K1
D2
RI0
RI2
JM6
RI DL
JM5
U1
C3
D3 D5
JW3
JW2
JW4
JW7
3 AMP
C
A09058
Fig. 14 -- Interface Fan Board (IFB)
Step 5 — Defrost Control
Defrost Control
The defrost control is used in all Puron (R--410A) heat pump
models. Its features include selectable defrost intervals of 30, 60,
90 minutes, and standard defrost speed up capability. This section
describes the sequence of operation and trouble shooting methods
for this control.
Defrost Sequence
The defrost control is a time/temperature control that has field
selectable settings of 30, 60, and 90 minutes. These represent the
amount of time that must pass after closure of the defrost
thermostat before the defrost sequence begins.
The defrost thermostat senses coil temperature throughout the
heating cycle. When the coil temperature reaches the defrost
thermostat setting, it will close, which energizes the DFT terminal
and begins the defrost timing sequence. When the DTF has been
energized for the selected time, the defrost cycle begins, and the
control shifts the reversing valve into cooling position, and turns
the outdoor fan off. This shifts hot gas flow into the outdoor coil
which melts the frost from the coil. The defrost cycle is terminated
when defrost thermostat opens, or automatically after 10 minutes.
677C
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C