*LCU DCV Quick Set-up for CV and MZVAV Light Commercial Units
This set-up guide is not for Multi-Speed, SZVAV, 17 SEER, or Precedent (WHC) High-Efficiency Heat Pumps (use for CV and MZVAV units only)
- Turn DCV MIN POS potentiometer full counterclockwise.
- Turn the DESIGN MIN POS potentiometer fully clockwise.
- Turn the LL pot to the 9 o’clock position.
- Turn the UL pot to the 12 o’clock position.
- Start the fan and verify between 1 to 2 volts on the RTEM DCV terminals (low CO2)
- Set the DCV Min Pot (0 - 40% damper position) this is your minimum position with low CO2.
- Simulate high CO2 by one of the following methods:
- Use a 9-volt battery.
- Have someone breathe into the CO2 sensor.
- The damper should start to move.
When using a Trane BAYCO2K00**, be sure to wire the CO2 sensor for 0-10 VDC output as shown below, then you don’t have to worry about the Out2 Jumper position.
With these settings:
When the CO2 level gets to approximately 600 PPM the damper should start opening.
When the CO2 level gets to approximately 1550 PPM the damper be at 50% (full open for DCV)
LL, UL, DCV MIN and DESIGN MIN can be readjusted later for local codes.
Notes:
DCV MIN POS sets your minimum position.
DESIGN MIN POS sets the maximum the CO2 sensor will drive the damper to.
LL (adjustable from 300 - 1900) is the CO2 level where you want the damper to start to open.
Approximate position values - 9 o'clock is 600 ppm, 12 o'clock is 1150 ppm, 3 o'clock is 1850 ppm
UL (adjustable from 500 - 2000) is the CO2 level where the damper would be max open.
Approximate position values - 9 o'clock is 1200 ppm, 12 o'clock is 1550 ppm, 3 o'clock is 1950 ppm
The image below shows the CO2 connection to the RTEM (economizer module)
CO2 levels and associated voltages
.
WARNING:
Information in this article is intended for use by individuals possessing adequate backgrounds of electrical and mechanical experience and who comply with all federal, state, and local laws, rules, orders, or regulations related to the installation, service, or repair of a heating or central air conditioning product. Any attempt to install, service, or repair a heating or central air conditioning product may result in personal injury and/or property damage. The manufacturer or seller cannot be responsible for the interpretation of the information contained herein, nor can it assume any liability in connection with its use.