Daikin Enfinity Installation And Maintenance Manual page 29

■ Thermostat fault reset (preferred method) – A
feature to reset some lockouts like high pressure and/
or low temperature remote from the unit is available.
When the cause of the fault condition has been fixed,
repaired or resolved, the unit can be reset from the
thermostat. To reset the fault, move the system switch
on the thermostat from its current position (Heat/Auto/
Cool) to the Off position and back to its original position
two times within 30 seconds. The unit will now be reset.
The intelligent reset counter and the 24 hour timer are
cleared.
CAUTION
Some thermostats have internal timers greater than 30
seconds that delay their switching capabilities. Defeating
their internal timers may be required to reset the fault
using the thermostat.
Alternatively, thermostats as shown in
on page 39 have an optional "reset" feature, by
activating the reset feature and adding a wire from
terminal O to terminal TB1, pin 4, on the MicroTech III
board.
■ Reset of automatic lockouts (alternate method) - A
feature to reset some lockouts like high pressure and/
or low temperature at the unit is available. When the
cause of the fault condition has been fixed, repaired
or resolved, the unit can be reset at the unit. Apply a
grounded signal to the tenant override input (screw
terminal connection at TB1, pin 4) for a minimum of
10 seconds. The unit will now be reset. Alternatively,
dropping power to the unit from the disconnect switch
and re-applying power will reset the unit.
■ Intelligent alarm reset – The Intelligent Reset feature
helps to minimize nuisance trips of automatic lockouts
caused by low-temperature faults. This feature clears
faults the first two times they occur within a 24-hour
period and triggers an automatic lockout on the 3rd
fault. The fault remains active until the alarm is manually
cleared. At the end of the 24 hour period, all counts for
that specific intelligent reset alarm are cleared to zero
only if the occurrence counter is presently less than the
value of three. The 24-hour period and alarm counts are
stored in memory that is cleared when power is cycled.
IM 1059-12 LARGE VERTICAL WSHP
■ Selectable lead compressor – The lead compressor
selection provides a method to utilize circuit 2 if repairs
are required on circuit 1. This is not intended for normal
equipment operation. The jumper setting JP8 in the
I/O expansion board is used to configure the "Lead
Compressor" settings.
■ Lead compressor fail replacement – Upon detection
of a lead compressor fault and the lag compressor is
available, the selected lead compressor will be "failed
replaced" by the lag compressor. Lead compressor will
immediately be de-energized by ignoring the compressor
minimum ON timer. Lag compressor will energize
in place of the failed lead compressor, when the lag
compressor minimum OFF timer has expired. Reversing
valve for the lag compressor will be positioned, if
necessary, 5 seconds after the lag compressor starts up.
■ Equipment protection control – The MicroTech III
controller receives separate input signals from
Figure 25
the refrigerant high-pressure switch and the low
suction line temperature sensor. In a high-pressure
situation, compressor operation is suspended. In a
low temperature situation, the unit goes into a defrost
cycle where the unit is put into cooling operation for 60
seconds until the coaxial heat exchanger is free of ice.
Each switch generates its own unique LED status.
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C
ontrols
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