Goodman ACVC8 CA Series AMVC8 CA Series Service And Troubleshooting page 7

SYSTEM OPERATION
NOTE: Do not use gas piping as an electrical
ground. To confirm proper unit grounding,
turn off the electrical power and perform the
following check.
1. Measure resistance between the neutral (white)
connection and one of the burners.
2. Resistance should measure 10 ohms or less.
This furnace is equipped with a blower door interlock
switch which interrupts unit voltage when the blower door is
opened for servicing. Do not defeat this switch.
EXTREMELY IMPORTANT: This system does not
contain an O wire input (reversing valve signal).
If a heat pump is installed, the thermostat should
be setup for single stage heat/single stage
cool installs ( W= Heat Call and Y = Cool Call).
Setting thermostat for heat pump control will
result in incorrect performance.
Quick Start Guide
1. Connect all necessary thermostat wires to the thermostat
connector on the furnace control (only available
connections on the furnace are R & C for power, Y for
Cooling Calls, W for Heating Calls, G for Fan Calls,
Dehum for Dehumidification Calls. Furnace will control
staging of indoor unit and outdoor unit automatically
based on these inputs).
2. Make sure thermostat is set to single stage heat / single
stage cool mode. When a cool call is given, 24VAC
should be applied to the Y terminal (G will have 24VAC
as well if a G wire is installed). When a heat call is given
24VAC should be applied to the W terminal (G may
have 24VAC as well if a G wire is installed). Even if a
heat pump is installed, do not setup the thermostat in
heat pump mode. Single stage heat / single stage cool
mode is all that is required for all applications. See rest
of manual for any exceptions. Do not setup thermostat
in multi stage mode either, it is not necessary.
3. For communicating 2 stage AC/HP or inverter AC/
HP outdoor units, connect the 1&2 wires between the
indoor and outdoor unit. It is recommended for 2 stage
applications that a separate transformer be installed in
the outdoor unit to provide 24VAC to the outdoor control.
R&C can be used between the indoor and outdoor in
2 stage AC application but only if there isn't already a
transformer installed in the outdoor unit.
4. Turn on power to Indoor and Outdoor units
5. Charging outdoor unit: Provide a cooling call (Y or
Y+G) – this initial cooling call after the power is turned
on will run the outdoor unit at full capacity until the call
is removed. Use this mode for charging. If system is
running low stage cooling just cycle power and provide
a cool call again to ensure full capacity cooling.
6. System Testing: Download the CoolCloudHVAC phone
application (see pages 31 and 32)and use it to test all
operations of both indoor and outdoor units.
7. Confirm thermostat heat (W or W+G) and cool (Y or
Y+G) function properly and the system is turning on in
the correct mode. The internal algorithms will constantly
be adjusting the staging times / cooling capacities based
on load changes to the space.
NOTE: If a heat pump is installed it will be treated
as a priority heat for a W call. To test gas heat
only, without waiting for the system to stage
between the heat pump and furnace, disconnect
communications between the indoor and outdoor
unit before running the heating test.
Control System – General Information
The furnace contains internal logic to control equipment
staging. An adjustable target runtime is available (range
from 1 to 240 minutes) and set through the appropriate
system menu. The system will constantly be adjusting
staging in an effort to satify the thermostat call for cooling
(Y only) or heating (W Only) as close to the set target
runtime as possible. See information below for setting
options.
Comfort Setting Menu (CFS)
There are 6 options available in the Comfort Setting
Menu which impacts both the System Target Runtime and
Dual Fuel Operation. Dual Fuel operation adjustments
only apply if a communicating heat pump is installed.
Comfort Setting Options 1 – 5 have set values for the
System Target Runtime and option 6 enables additional
menus to customize all comfort settings. See list below
for the System Target Run times associated with the first
5 Comfort Settings. These first 5 options are setup to
help satisfy the thermostat slower or faster based on the
selection where option 1, with a 10 minute Target Runtime,
is attempting to satisfy much faster than option 5, with a 30
minute Target Runtime.
System Target Runtime
Comfort Setting Option 1) 10 Minute System Target
Runtime
Comfort Setting Option 2) 15 Minute System Target
Runtime
Comfort Setting Option 3) 20 Minute System Target
Runtime
Comfort Setting Option 4) 25 Minute System Target
Runtime
Comfort Setting Option 5) 30 Minute System Target
Runtime
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