HP - A 4
Sequence Of Operation
16 SEER Sequence of Operation
Refer to the schematic diagram on page 3
Charge Assist™
See the Service Facts in the outdoor unit for detailed information
on the Charge Assist™ feature.
MODE button: To enter the Charge Assist™ feature, press the
MODE button for 2 seconds.
6) CHARGING LED: When using the Charge Assist™ feature to
commission a system or check the charge level, this LED will
flash to indicate the start of the stabilization mode. The LED
flash rate will get faster the closer the system is to determining
the charge level.
7) ADD LED: When using the Charge Assist™ feature to
commission a system or check the charge level, this LED will
turn ON if the operation calculates that the system subcooling
level is low. Should the ADD LED turn ON, 24 volts AC will be
provided from terminals T3 and T4 of the Charge Assist™ control
board to power a charging solenoid, if used. Note: See the
instructions supplied with the BAYCAKT001A (Literature number
18-HH15D1-1). When the charging solenoid receives power,
the valve will open allowing refrigerant to flow from a supply
bottle to the outdoor unit via the Charging Port located near the
service valves. Once enough refrigerant has been added to
meet the subcooling requirement for the system and the
calculated charge level has been achieved, the control will stop
sending 24 volts AC from T3 &T4 de-energizing the charging
solenoid ending the flow of refrigerant to the system. At this
time the ADD LED will turn OFF and the CHARGED LED will turn
ON.
8) CHARGED LED: Utilized as an indicator during Charge Assist™
to acknowledge when the system charge is deemed to be “on
target” for the calculated subcooling level. DIP Switch settings
are required for the Charge Assist™ function to modify the
subcooling level based on line length and lift.
9) REC LED: This LED (Recover) will turn ON if the operation
calculates that the system subcooling level is high. Should the
REC LED turn ON, the system will be turned OFF for up to one
hour with the REC LED illuminated. The one hour lockout can be
exited by pressing the MODE button for two seconds or by
cycling power to the outdoor unit.
10) LOW Pressure LED: System pressure must be at least 90
psi (R-410A) to enter Charge Assist™. If system pressure is
sensed to be low, based on input from the Liquid Pressure
Transducer, this LED will turn ON for 30 seconds followed by
10 fast flashes from the CHARGING LED. These actions indicate
that Charge Assist™ was not allowed.
11) ODT Out Of Range LED: Outside temperature must be at
least 55 degrees F to enter Charge Assist™. If the outside
temperature is sensed to be low, based on input from the Ambient
Temperature Sensor, this LED will flash for 30 seconds followed
by 10 fast flashes from the CHARGING LED.
12) DS13 LED: Functions only to transmit LitePort data which
requires an optic coupler and accompanying software to monitor
or record outdoor unit performance.
Power Interrupt Delay
Power Interrupt protection is part of the control logic to prevent
short cycling of the compressor due to brief power interruptions
(0.1 to 1 second in duration). 24 volt AC power is required as an
input to the control at pin 11 of the J1 connector in order for
the power interrupt logic to work. If power is missing on pin 11
of the J1 connector, the control board will send an Error 18
message to the comfort control and begin to flash the FAULT
LED 18 times. If this fault is present, all system operations will
be allowed however; the fault indication will persist until the 24
volt input to J1-11 is restored. Power Interrupt protection, if
activated, will de- energize 24 volts AC to the contactor and
hold off compressor operation for approximately 70 seconds.
The STATUS LED plus the Y1 and/or Y2 LEDs will flash for the
duration of the Power Interrupt delay. If a power-off cycle lasts
2 seconds or longer, the Minimum Equipment Off Timer (5 minutes)
will be enforced by the Comfort Control.
Heat Pump Cooling Mode of Operation
When a heat pump system receives a demand message for
cooling capacity, in addition to the compressor contactor and
outdoor fan control signals, there is also a 24 volt AC output
from plug J3/3 (O) to energize the switch over valve (SOV)
solenoid coil. The SOV solenoid coil will be energized with
the start of the first call for cooling and remains energized until
the next call for compressor heat so long as the comfort control
stays in the cooling mode of operation. Even if the comfort
control is switched to the heating mode of operation, the SOV
will not be de-energized until the first call for compressor
heat is received.
Heat Pump Heating Mode of Operation
When a heat pump system receives a demand message for
heating capacity, the SOV solenoid coil will not be energized
unless a defrost cycle occurs. When transitioning from the
cooling mode of operation, the SOV will be de-energized with
the start of the first call for heating and will remain de-energized
until the next call for compressor cooling so long as the comfort
control stays in the heating mode of operation.
13
13
2
1
13
14
15
15
15
To Next Page
Loading...
