Desert Aire Aura QS, Installation And Operation Manual

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Oil charge has been confirmed at the factory. In the rare case that the compressor is observed to
ramp up for oil return more than twice per hour, 20 oz additional POE oil should be added to the
system.
While in steady state operation, record the data required for the start-up report. If the compressor is
at maximum speed in steady state operation, it may be operating outside of design conditions. Check
the air flow to verify excessive airflow is not limiting the dewpoint capabilities of the unit. If the
dewpoint set point was adjusted, return it to its original value.
For TotalAire™ and VerticalAire™ Products
In order to test the unit in dehumidification / cooling mode, the air temperature entering the DX
evaporator must be approximately 50°F or higher. If the condition entering the unit is lower, the unit
may experience difficulties resulting in poor operation or shutdown due to low suction pressure.
If a low outdoor air temperature condition prevents the unit from running long enough to take data,
note this on a startup report and proceed to heat pump mode. During the first Preventative
Maintenance visit that is recommended during spring and fall, the service contractor should complete
the Dehumidification/Cooling Mode section of the startup report.
To perform start-up checks on the compressor, the supply air dewpoint set point should be lower
than the incoming dewpoint by at least 10°F. See the Controller IO Manual for instructions on setting
the dewpoint set point. Note the original setting. Once the set point is adjusted, switch the unit to
occupied mode.
It can take up to 15 minutes for the unit to reach steady state. While in steady state operation, record
the data required for the start-up report. If the dewpoint set point was adjusted, return it to its original
value.
3.4.2 Heat Pump Mode
For Aura™ Products
In order to test the unit in heat pump mode, the air temperature entering the reheat condenser must
be approximately 90°F or lower. If the condition entering the condenser is higher, the unit may run
elevated head pressures and a high discharge pressure alarm may occur.
If a high outdoor air temperature condition prevents the unit from running long enough to take data,
note this on the startup report. During the first Preventative Maintenance visit that is recommended
during spring and fall, the service contractor should complete the Heat Pump Mode section of the
startup report.
To perform start-up checks on the compressor in heat pump mode, the supply air temperature
set point should be higher than the incoming air temperature by at least 10°F. See the Controller IO
Manual for instructions on setting the supply air temperature set point. Note the original setting.
Once the set point is adjusted, switch the unit to occupied mode.
Desert Aire - QS/QV Manual