CAC Cassette Evaporator

REMOTE THERMOSTAT OPERATION for CAC Ductless Split Air Handler

Choosing a Thermostat: EMI offers several remote thermostats that are com- patible with the Ductless split system air handlers. See the latest price list for a list of available thermostats. It is important to choose a thermostat that will match the equipment that you have selected. For single stage cooling or hearting choose a single stage Heat/Cool thermostat.

Selecting a Thermostat “By Oth- ers”: When selecting a thermostat other than those offered by EMI, it is important to choose a 24V thermostat that matches your application. EMI equipment is com- patible with most mercury bulb, digital or power stealing thermostats.

Cooling Only With Electric Heat or Hydronic Heat: Select a thermostat that is compatible with a cooling - electric heat system. The thermostat should have “R”, “Y”, “W” and “G” terminals. The thermo- stat may also have a “C” terminal.

Fan Operation: Some thermostats are equipped with an auto/on fan switch. When this switch is placed in the on po- sition the indoor fan will run continuous. When the switch is in the auto position the indoor fan will cycle with the call for heating or cooling.

Fan Purge: The indoor unit is equipped an electronic circuit board with a purge feature. After the room thermostat has been satisﬁed, the purge feature al- lows the indoor fan to remain on for an additional 60 seconds. This increases ef- ﬁciency by pulling the remaining energy from the unit.

Cooling Operation: The electronic circuit board of the indoor unit also has an anti-short cycle timer (ASCT) feature designed to protect the compressor from short cycling. The ASCT is activated im- mediately following the off cycle of the outdoor unit. Once the room temperature is satisﬁed and the outdoor unit switches off, the ASCT will prevent the outdoor from restarting unit after a three-minute time period has elapsed.

After connecting the thermostat to the unit place the system switch in cool mode. Ad- just the set-point temperature below the room temperature. The compressor and fan motors will start and cooling will begin. For chilled water systems, the coldwater valve will open allowing the ﬂow of water. Place the set-point temperature above the room temperature. The outdoor con- denser will stop (or CW valve will close) while the indoor fan will remain on for an additional sixty seconds.

Electric Heat Operation (Optional): Place the thermostat system switch in heat mode. Adjust the set-point tempera- ture above the room temperature. The electric heat will energize along with the indoor fan motor. Heating will continue so long as the set-point remains above room temperature. Next place the set-point temperature below room temperature. The Electric heater will switch off and the indoor fan will remain on for an additional sixty seconds.