SmartZone-4X - FRESH AIR CONTROL

Built in to the SmartZone-4X, fresh air (outside) air can be controlled. Below shows the wiring and configuration for the basic version of fresh air which meets ASHRE 62.2 standards. SmartZone has additional “advanced” fresh air options that can be controlled to further take advantage of the fresh air system if installed. Accessories such as an enthalpy controller or a fresh air thermostat can be added to the system to enhance the fresh air experience and use. Scroll down for more information about these advanced features.

ADVANCED FEATURES

 The advanced features of the SmartZone-4X Fresh Air System can be enabled using the ZONE-4 Thermostat input. A simple “dry-contact” switch can be connected between the “R” terminal and the “Y”, “G”, “W” or “O” terminals to activate the different advanced features.

• Y - ECONOMIZER MODE
  If Zone 4 set to “FRESH AIR MODE” the Y terminal on Zone 4 can be energized by any 24VAC input to activate “ECONOMIZER MODE” When in this mode any cooling calls from other zones will initiate ECONOMIZER RUN:

  • Fresh Air Damper (Zone 4) will open & Equipment Fan (G) will energize

  • Zone Damper(s) calling for cooling will open

  • Equipment compressor (Y) will not energize initially

  • Supply temperature will be monitored and fresh air damper closed if it drops below low temp limit and compressor energized after 3 minutes if the supply temperature is above the ECONOMIZER MODE LIMIT.
    ECONOMIZER MODE LIMIT is set by holding the down arrow button for 5 seconds

• G - FRESH AIR ON DEMAND
  Energizing the G terminal on Zone 4 will turn FRESH AIR MODE ON. This means the fan comes on and the fresh air damper opens. Any zone that is concurrently open will get outside air.

• W - FRESH AIR ONLY WITH EQUIPMENT
  If some # of minutes have been set for automatic run time of the FRESH AIR mode, the W terminal can be energized so that the fresh air DOES NOT run unless the equipment is also running. Some choose to set this permanently with a jumper wire from R to W, so that fresh air is only energized if the equipment runs. NOTE: the number of minutes set in the setup of fresh air above will serve as a MAXIMUM number of minutes because if the equipment doesn’t run at all during a given hour then the fresh air will not either.

• O/B - DISSABLE FRESH AIR
  If the terminal O/B on zone 4 is energized, no fresh air will run. It is an OFF switch for the fresh air control system. This allow for the use of an accessory to disable fresh air when the temperature is too hot or cold outside or when out of town, etc.

FRESH AIR THERMOSTAT (OUTDOOR AIR)

Ecojay offers a “OUTDOOR AIR THERMOSTAT” accessory that is intended to enhance some of these advanced fresh air features. It includes an outdoor temperature sensor and controls that allow for the user to set temperature range for fresh air as well as the ability to demand fresh air with a timer & and to manually disable fresh air temporarily or permanently.

ENTHALPY CONTROL

To utilize ECONOMIZER mode effectively, the outdoor air conditions need to be measured accurately to tell the SmartZone-4X when to enable it. This is not just temperature but also humidity. When you measure both temperature and humidity, you can calculate enthalpy which is the technical way of telling whether or not the air will “feel” cool to a human. This is essentially what the “feels-like” temperature is when you hear tv weather broadcasts. So, ECOJAY, offers a simple device that can connect to the Y terminal of the Zone-4 on SmartZone when installing an ECONOMIZER to enable the mode only when outdoor conditions are favorable.
(ENTHALPY CONTROLLER)