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24. FILTERS
A 2" thick throwaway filter is supplied with each unit.
This filter is installed by opening the main service
door. (See Figure 14.)
Replacement filters are available through your dealer.
25. COMPRESSOR CONTROL MODULE
The compressor control is an anti-short cycle/lockout
timer with high and low pressure switch monitoring
and alarm output.
ADJUSTABLE DELAY-ON-MAKE AND BREAK
TIMER
On a call for compressor operation the delay-on-make
period begins which will be 10% of the delay-on-break
setting. When the delay-on-make is complete and the
high pressure switch (and low pressure switch if
employed) is closed, the compressor contactor is
energized. Upon shutdown the delay-on-break timer
starts and prevents restart until the delay-on-break and
delay-on-make periods have expired.
Manual 2100-376
Page 29
FIGURE 14
ACCESS INTERNAL FILTER
THROUGH UPPER SERVICE DOOR
HIGH PRESSURE SWITCH AND LOCKOUT
SEQUENCE (Standard Feature)
If the high pressure switch opens, the compressor
contactor will de-energize immediately. The lockout
timer will go into a soft lockout and stay in soft lockout
until the high pressure switch closes and the delay-on-
make time has expired. If the high pressure switch
opens again in this same operating cycle the unit will
go into manual lockout condition and the alarm circuit
will energize. Recycling the wall thermostat resets the
manual lockout.
LOW PRESSURE SWITCH, BYPASS, AND
LOCKOUT SEQUENCE
NOTE: The low pressure switch is an optional
control and the bypass and lockout sequence
are part of the standard compressor control
module.
If the low pressure switch opens for more that 120
seconds, the compressor contactor will de-energize and
go into a soft lockout. Regardless the state of the low
pressure switch, the contactor will reenergize after the
delay-on-make time delay has expired. If the low
pressure switch remains open or opens again for longer
than 120 seconds the unit will go into manual lockout
condition and the alarm circuit will energize.
Recycling the wall thermostat resets the manual
lockout.
MIS-1449
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