GVZC20 Installation Manual

53
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This menu allows for the setting of BOOST MODE.
BOOST MODE enables the system to operate at a higher
compressor speed than maximum compressor speed.
BOOST MODE set temperature can be adjusted in BOOST
TEMP menu. When ambient temperature gets higher than
BOOST MODE set temperature, the system will operate in
BOOST MODE.
Equipment Test
The mandatory system verication test is enabled from this
menu, which enables a functional check of the equipment, in
addition to ensuring proper stop valve position.
Maintenance
Pump down and charge modes can be enabled within this
menu.
Cool Set-up
This menu allows for the adjustment of several cooling
performance variables. Cool Airow Trim, Cool Airow
Proles, Cool Fan ON Delay, Cool Fan OFF Delay and
Dehumidication Select (some enable option or o󰀨) can
be adjusted in this menu. You can also reset this entire
menu to factory default settings. See the following images
showing the four cooling airow proles.
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•  provides only an OFF delay of one (1) minute
at 100% of the cooling demand airow.
•  ramps up to full cooling demand airow by rst
stepping up to 50% of the full demand for 30 seconds.
The motor then ramps to 100% of the required airow.
A one (1) minute OFF delay at 100% of the cooling
airow.
50% CFM
1/2 min
100% CFM
100% CFM
1 min
OFF
OFF
•  ramps up to 82% of the full cooling demand
airow and operates there for approximately 7 1/2
minutes. The motor then steps up to the full demand
airow. Prole C also has a one (1) minute 100% OFF
delay.
100% CFM
OFF
OFF
•  (default) ramps up to 50% of the demand
for 1/2 minute, then ramps to 82% of the full cooling
demand airow and operates there for approximately
7 1/2 minutes. The motor then steps up to the full
demand airow. Prole D has a 1/2 minute at 50% airow
OFF delay.
OFF
OFF
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Dehumidication requires a thermostat capable of reading the
indoor humidity level from the thermostat and allows the user
to set a dehumidication target based on these settings.
The thermostat controls the humidity level of the conditioned
space using the cooling system. Dehumidication is
engaged whenever a cooling demand is present and
structural humidity levels are above the target level. When
this condition exists, the circulating fan output is reduced,
increasing the system run over time, over cooling the
evaporator coil and ultimately removing more humidity from
the structure than if only in cooling mode.
The thermostat may also allow for an additional overcooling
limit setting depending on the thermostat utilized. This allows
the cooling system to further reduce humidity by lowering
the temperature below the cooling setpoint in an attempt to
better achieve desired humidity levels.
When Dehumidication mode exists, the circulating fan
output is reduced, increasing system run time, over cooling
the evaporator coil and ultimately removing more humidity
from the structure than if only in cooling mode.
The system can have Dehumidication operation in setting
“STD”, “A”, “B” or “C” of “Dehumidication Select” based on
dehumidication demand.
Setting “STD” allows for the widest compressor operation
range with lower CFM than Cooling mode.
In the Enhanced Dehumidication (setting A, B and C)
the indoor airow is lower than Standard Dehumidication
(STD).
Setting “A” allows for the same compressor operation
range as standard Dehumidication with lower CFM than
standard dehumidication (STD).
Setting “B” limits compressor operation range and keeps
high dehumidication capacity.
In setting “C” the system runs xed at 100% compressor
and airow. See Figure 1.