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Installation Instructions — CMA-11
Disconnect all power to unit. Remove control panel inner cover.
Step 1.
Snap control assembly into control panel as shown in
Figure 5.
Step 2.
Disconnect yellow low voltage (Y) wire at compressor
contactor coil or (Y1) at optional CMA-5 and reconnect
to terminal #4 of the lockout relay.
Step 3.
Connect the black wire from terminal H of the low
pressure bypass TDR to the common (C) side of the
compressor contactor coil.
Step 4.
Connect yellow wire from terminal #1 or (Y) of the low
pressure bypass relay to the (Y) terminal of the
compressor contactor coil or (Y1) at optional CMA-5.
This is the terminal that the wire was removed from in
Step 2.
Step 5.
Route high (red) and low (blue) pressure switch wires
up through the bushing in the bottom of the control
panel. Connect the high pressure switch wires between
terminal #5 of the lockout relay and terminal #1 of the
low pressure bypass TDR.
Step 6.
Connect low pressure switch wires between terminals
#1 and #3 of the low pressure bypass TDR.
Step 7.
Disconnect black high voltage outdoor motor lead from
compressor contactor and reconnect to terminal block.
Step 8.
Route low ambient control wires up through the
bushing in the bottom of the control panel. Connect the
low ambient control wires between the terminal block
and T2 of the compressor contactor.
Step 9.
Remove service port caps on both the suction and
discharge lines. Install the high pressure switch and low
ambient control on the discharge line with the flare tee
adapter that is brazed to the controls. Install the low
pressure switch on the suction line. Check for pressure
at the flare tee dill valves after installation to insure that
the dill valve in the unit service port was depressed by
the flare tee connector. Check for leaks at the flare tee
connectors. Replace service port caps on the flare tee
service ports and tighten.
Step 10.
Recheck wiring. Refer to Figure 11. Energize unit in
first stage cooling. Compressor should start. Run the
unit for at least 5 minutes. The unit should not go into
lockout. The condenser fan motor should not run until
the discharge pressure has exceeded 300 PSI. Should
the discharge pressure fall below 200 PSI while
running, the condenser fan motor will de-energize until
the head pressure builds to 300 PSI.
Step 11.
Apply "This unit equipped with CMA-11 control
module" label to the inside of the inner control panel
cover above the wiring diagram.
Step 12.
Replace all panels and covers. This completes
installation.
Figure 11 — Installation Instructions for CMA-11
Dual Pressure and Low Ambient Fan
Cycling Control
MIS-593
Page 11
Manual 2100-292
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