Manual
2100-510E
Page
25 of 38
COMPRESSOR CONTROL MODULE
The compressor control module 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 are 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.
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 the
same operating cycle, the unit will go into
manual lockout
condition and the alarm relay circuit will energize.
Recycling the wall thermostat resets the manual lockout.
LOW PRESSURE SWITCH, BYPASS AND
LOCKOUT SEQUENCE (Standard Feature)
If the low pressure switch opens for more than 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
in the same operating cycle, the unit will go into manual
lockout condition and the alarm relay circuit will energize.
Recycling the wall thermostat resets the manual lockout.
ALARM OUTPUT
Alarm terminal is output connection for applications where
alarm signal is desired. This terminal is powered whenever
compressor is locked out due to HPC or LPC sequences as
described.
Note:
Both high and low pressure switch controls are
inherently automatic reset devices. The high pressure
switch and low pressure switch cut out and cut in settings
are fixed by specific air conditioner or heat pump unit
model. The lockout feature, both soft and manual, are a
function of the Compressor Control Module.
PRESSURE SERVICE PORTS
High and low pressure service ports are installed on all
units so that the system operating pressures can be
observed. Pressure tables can be found later in the manual
covering all models. It is imperative to match the correct
pressure table to the unit by model number.
SYSTEM START-UP
Step 1 – Close disconnect switch(es) and set the
thermostat to cool and the temperature to the
highest setting.
Step 2 – Check for proper airflow across the indoor coil.
Step 3 – Connect the service gauges and allow the unit to
run for at least 10 minutes or until pressures are
stable. Check pressures to the system pressure
table attached to the unit service panel.
Step 4 – Fill out Ground Source Heat Pump Performance
Report.
SEQUENCE OF OPERATION
