Testing Temperature Sensors; (Comfortnet Ready Models Only); S-40A Avptc/Mbvc Electronic; Blower/Heater Control - Goodman ComfortNet ASXC Series Service Instructions Manual

SERVICING
2. Press TEST and RECALL buttons simultaneously for
approximately 3 seconds, then release them. System
should go into defrost immediately.
3. Using VOM check for voltage across terminals "C & O".
Meter should read 24 volts (skip this step if system a fully
communicating system)
4. Visually inspect to see that the frost is gradually melting
on the coil and the compressor is running.
5. Using VOM check for voltage across "W2 & C" terminals
on the board. You should read 24 volts.
6. If not as above, replace control board.
7. Set thermostat to off position and disconnect power
before removing any jumpers or wires.
S-26 TESTING TEMPERATURE SENSORS

(COMFORTNET READY MODELS ONLY)

The ASXC and DSXC ComfortNet ready air conditioner
models are factory equipped with an outdoor air tempera-
ture (OAT) sensor. The OAT sensor allows the outdoor air
temperature to be displayed on the CTK0* thermostat when
used with the ASXC and DSXC models.
The ASZC and DSZC ComfortNet ready heat pump models
are equipped with both an outdoor air temperature (OAT)
sensor and an outdoor coil temperature (OCT) sensor. The
OAT provides the balance point temperature in heat pump
systems (air handler w/electric heat + heat pump) and dual
fuel systems. The OCT sensor is provides the outdoor coil
temperature and is used in determining defrost cycles.
To check either the outdoor air or outdoor coil temperature
sensors:
HIGH VOLTAGE!
Disconnect ALL power before servicing
or installing. Multiple power sources
may be present. Failure to do so may
cause property damage, personal injury
or death.
1. Disconnect power to the air conditioner or heat pump.
2. Disconnect the sensor from the unitary (UC) control.
3. Connect an ohmmeter across the sensor terminals. The
ohmmeter should read be 10kΩ, +/-10%, at 75°F.
Replace the sensor if the sensor is open, shorted, or
outside the valid resistance range.
86
Ohm Reading of Communicating Outdoor Unit Sensors
T, °F RW@T T, °F RW@T T, °F RW@T T, °F RW@T T, °F RW@T
-40 336,000 5 72,940
-31 242,700 14 55,319
-22 177,000 23 42,324
-13 130,400 32 32,654
-4 97,060 41 25,396
S-40A AVPTC/MBVC ELECTRONIC BLOWER/
HEATER CONTROL
Description
The AVPTC and MBVC models utilize an electronic control
that provides ECM blower motor control and control of up to
two electric heat sequencers. The control has thermostat
inputs for up to two stages of cooling, two stages of electric
heat, reversing valve, and dehumidification. Control input is
24VAC.
All dipswitches necessary to setup cooling, heat pump, and
electric heat airflow are fully integrated into the control.
Dehumidification is enabled/disabled via an on-board
dipswitch.
Features
The new air handler control includes advanced diagnostic
features with fault recall, estimated CFM display via on-
board LED, and ComfortNet
heater kit selection diagnostics, open fuse, internal control
fault, data errors, and blower motor faults. Data errors are
not included in the fault recall list. Diagnostic error codes are
displayed on a single red LED.
The estimated CFM is displayed as a flashing green LED.
The LED flashes once for each 100 CFM.
The AVPTC/MBVC air handlers may be used in a fully
communicating ComfortNet system when matched with a
compatiable outdoor unit and the CTK0* thermostat. A fully
communicating system offers advanced setup and diagnos-
tic features.
Basic Operation
The air handler control receives thermostat inputs either from
a standard 24VAC thermostat or the CTK0* ComfortNet
thermostat. For cooling and heat pump operation, the
control operates the variable speed blower motor at the
demand as determined from the thermostat input(s). If a
demand for electric heat is received, the control will provide
a 24VAC output for up to two electric heat sequencers.
50 19,903 95 6,530 140
59 15,714 104 5,327 149
68 12,493 113 4,370 158
77 10,000 122 3,603 167
86 8,056 134 2,986 176
TM
ready. Diagnostics includes
2,488
2,083
1,752
1,480
1,255