Scholar V VAIVA Maintenance & Service Manual 10/2017 Rev.2
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Heating
• Press the Heating button on Screen 1. If the room temperature is less than or equal
to the heating set point, the compressor should come on. This may take up to 60
seconds, based on the setting of the ASCT setting.
• Both outdoor coil blowers should come on.
• The indoor blower should come on. It will run continuously if the blower is set to
ON, It will cycle with the compressor if set to AUTO. If set to AUTO, it will run for a
period of time after the compressor turns off, based on the Post Purge time setting.
• If the room temperature is considerably lower than the heating set point, the com-
pressor speed will ramp up slowly until the maximum control voltage is provided to
the compressor controller. This sets the maximum compressor speed and maximum
unit heating.
• If the room temperature is slightly above the heating set point, the compressor
speed will ramp. down until the minimum voltage is provided. This sets the mini-
mum compressor speed and minimum unit heating capacity.
• When the room temperature is approximately equal to the set point (inside the
control band explained in Screen 4), the compressor speed stops changing and
stays fixed.
• As the compressor speed changes, the indoor blower speed will also change. The
higher the compressor speed, the higher the indoor blower speed. This is to main-
tain a relatively constant supply air temperature.
• The reversing valve is de-energized in heating.
• If the Occupied Mode has been set, the ventilation fan will come on. This will stay
on continually.
• If pre-conditioning has been set to ON, outside air ventilation is disabled.
• No active relative humidity control is used in the heating mode.
Emergency Heat
• Press the Emergency Heat button on Screen 1.
• The heat pump heating mode is disabled.
• Heating is now provided by electric resistance heat. The same set-points are used
for resistance heat as heat pump heat.
• The compressor does not run.
• Indoor air flow is set to the maximum.
OFF
• Press the OFF button on Screen 1.
• All equipment in the unit turns off.
Auto Heat/Cool
• When Auto Heat/Cool is pressed, the system will automatically switch from cooling
to heating whenever the inside temperature drops below the heating set point, and
vice-versa
Manual Heat/Cool
• When Manual Heat/Cool is pressed the desired operating mode must be chosen by
pressing Cool, or Heat.
