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INSTALLATION
The Emerson Zoning System-3 is a two (2) and three (3) zone control
panel for single stage heating only, cooling only or heating and cool-
ing. The CMM-3 can control any single stage gas-oil-electric furnace,
hydro-air heating and air conditioning. The CMM-3 panel is the cen-
tral control panel where all zone dampers, zone thermostats, HVAC
Equipment and power transformer are wired. When installing the
CMM-3 panel it is important to pick a central location where it is most
convenient to bring all the wires. Most often this is at the furnace or
air handler. It is often the most convenient location and closest to
power, the HVAC unit controls and the zone dampers when typically
located at or near the plenum.
The CMM-3 panel is made of sturdy ABS plastic and can be mounted
to any flat surface. It is recommended that the panel be mounted to a
wall or return plenum and NOT on the furnace or plenum where it will
be in contact with the high temperatures. The panel can be located
in an attic space or in an enclosed cabinet of a rooftop unit, provided
the panel enclosed and not in direct exposure to the elements. The
cover easily removes from the case by pulling firmly and separat-
ing the cover from the case exposing the circuit board. There are 4
key-hole mounting points in each corner of the case. The case has
openings in the rear of the case as well as the side for all wiring.
Wiring can come from the back as well as the side in order to make a
neat installation.
OPERATION
The CMM-3 can controls single stage heating and cooling HVAC
Equipment. The CMM-3 is compatible with any standard single stage
thermostat and setback thermostats as well. The CMM-3 has various
features that make installation and checkout very simple for all of the
board’s functionality. The CMM-3’s basic function is zone control. On
a call for heating or cooling, the panel will accept the first call from
any zone. Upon accepting this call the CMM-3 will keep open the
damper(s) to the zone calling; close the damper(s) to those zones
not calling, activate the needed HVAC controls for heating or cooling,
whichever is being called and not accept any calls for the opposite
mode.
Any calls for the opposite mode will be locked out until the initial
mode is either satisfied or a period of time has elapsed that is suffi-
cient for the first mode to satisfy, a maximum of 20 minutes. A Patent
Pending sequence determines the time the unit has been running or
needs to continue to run in order to adequately provide conditioning
for each mode. If a particular mode has already been calling for 20
minutes or longer and an opposite call comes in the CMM-3 will im-
mediately drop the mode, enter the purge mode in order to dissipate
the conditioned air into the zones calling before switching over to
provide the new conditioning call to its zones.
System Mode Indicator
Power Indicator LED
Fan Operation and
Test Jumpers
Boot Button
24V Transformer
Re-Settable Fuse
HVAC Equipment
Connections
Zone Terminal
Blocks for Zone
Thermostats and
Zone Damper
Motors
Zone Calling Indicators
Mounting Keyholes
Two at Top also
CMM-3
CMM-3K ZONE PANELS
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