Amana ASXC16, Service And Troubleshooting

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SERVICING
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1. Stage Up Percent (7 segment menu SUP): This is a
value that determines how far past the target runtime
the system should continue running the heat pump
before transitioning to the furnace. For example,
assume this menu was set to 20% with a target runtime
of 20 minutes. If the thermostat did not remove the
heating call after 20 minutes, the system would allow
for an additional 20% heat pump run (20% of the 20
minute target is an additional 4 minutes). In this case,
the system would turn on back up electric heat after 24
minutes if the thermostat call was still present. Each
time this occurs, the system records this as a strike
against the heat pump (the strike is important when
looking at the Over Target Threshold)
2. Over Target Threshold (7 segment menu Ott): If the
heat pump has consecutively activated back up electric
heat for the selected Over Target Threshold amount of
times, meaning for this many consecutive cycles it has
been unable to satisfy the target time by itself, then
the heat pump will be temporarily locked out and the
furnace will become the primary heat source.
3. Stage Down Percent (7 segment menu SdP): This
only applies when the heat pump and back up electric
heat are activated on initial start-up. In this case, the
system will try to determine when the best time to
operate the heat pump individually again. To determine
this, the system looks at how easily the air handler is
able to satisfy the thermostat using the heat pump with
back up electric heat. Assume this setting is 15% and
the target time is 20 minutes. If the heat pump with back
up electric heat can satisfy the thermostat in less than
17 minutes (20 minutes - 15% = 17 minutes) then the
algorithm records a strike against the air handler (this
strike is important when looking at the Under Target
Threshold).
4. Under Target Threshold (7 segment menu Utt): If
the air handler is able to satisfy the thermostat using the
heat pump with back up electric heat for the selected
number of consecutive cycles the electric heat operation
will be temporarily removed. The heat pump will then
be used during the next cycle. If the heat pump can
satisfy the thermostat in less than the System Target
Runtime the back up heat operation will be completely
removed and the heat pump will become the primary
heat source again. if it fails to do so, the strike count
against the furnace will be reset and the furnace will
remain the temporary primary heat source until the
Under Target Threshold is reached again.
The system will automatically make adjustments in an
attempt to satisfy the thermostat as close to this target
runtime as possible. After a power cycle or mode change
(cooling to heating or heating to cooling) the system will
run full capacity for the selected mode during the first
thermostat call. Based on the selected target runtime and
how long the initial cycle takes to satisfy the thermostat,
the control algorithm will adjust the system stage times for
a 2 stage unit or the capacity demand percentage for an
inverter / modulating unit for the next cycle. Note: actual
run times may change depending on variations of load
throughout the day.
The following table shows the default values for all Comfort
Setting Options (1 – 5)
Comfort
Setting
Option
Target
Time
(Minutes)
Stage Up
Percentage
(%)
Stage Down
Percentage
(%)
Over Target
Threshhold
(Strike Count)
Under Target
Threshhold
(Strike Count)
1 10 20 20 2 10
2 15 20 20 4 8
3 20 20 20 6 6
4 25 20 20 8 4
5 30 20 20 10 2
The following table shows the ranges for each of item
when the adjustable Comfort Setting Option 6 is selected.
The table shows the minimum value, the maximum value
and the defaulted value. All items can be adjusted up or
down by increments of 1 which provides full flexibility for all
items.
NOTE: It is critical that these numbers be set properly.
If Comfort Setting option 3 is desired but a target time
of 60 is preferred, select Comfort Setting Option 6 to
enable all the adjustable menus, set the Target Time
to 60 and make sure the other menus are set to match
that of Comfort Setting Option 3.
Menu Minimum Value Maximum Value Default Value
Target Time (t9t) 1 minute 240 minutes 60 minutes
Stage Up Percent (SUP) 0% 100% 20%
Stage Down Percent (SdP) 0% 100% 20%
Over Target Threshold (Ott) 1 strike 254 strikes 20 strikes
Under Target Threshold (Utt) 1 strike 254 strikes 20 strikes
Circulator Blower Speed
The Airflow quantity is displayed as a number on the three
7 segment displays, rounded to the nearest 100 CFM. The
display alternates airflow amount and the system operating
status.
Each furnace has a “Maximum CFM” it is capable of
providing. All fan operations (Constant CFM, Cooling
Airflow Profiles, Low and High Stage gas heat airflow,
outdoor Air Conditioner / Heat Pump Airflow, etc.) are
based off of multipliers which are percentages of this
maximum CFM.