AERCO C-More Controls Manual June 2010 - Manual (Page 68)

C-More Controller for Benchmark, Innovation & KC
USER MANUAL
Page 68 of 162 AERCO International, Inc. • 100 Oritani Dr. • Blauvelt, New York 10913 04/22/14
GF-112 Phone: 800-526-0288 OMM-0032_0E
Outdoor Air Temperature Sensor Installation
The outdoor air temperature sensor must be mounted on the North side of the building in an
area where the average outside air temperature is expected. The sensor must be shielded from
the sun's direct rays, as well as direct impingement by the elements. If a cover or shield is used,
it must allow free air circulation. The sensor may be mounted up to two hundred feet from the
unit. Sensor connections are made inside the Input/Output (I/O) Box at the terminals labeled
OUTDOOR SENSOR IN and SENSOR COMMON using shielded 18 to 22 AWG wire. A wiring
diagram is provided on the cover of the I/O Box. Refer to Section 2 of Operation & Maintenance
Manual GF-109 (KC Series) or GF-110 (Benchmark Series) for additional wiring information.
Indoor/Outdoor Startup
1. Refer to the indoor/outdoor reset ratio charts in Appendix B.
2. Choose the chart corresponding to the desired building reference temperature.
Go down the left column of the chart to the coldest design outdoor air temperature
expected for your area.
NOTE
A design engineer typically provides design outdoor air
temperature and supply header temperature data
3. Once the design outdoor air temperature is chosen, go across the chart to the desired
supply header temperature (setpoint) for the design temperature chosen in step 3.
4. Next, go up that column to the Reset Ratio row to find the corresponding reset ratio.
Access the Configuration Menu and scroll through it until the display shows Bldg Ref
Temp (Building Reference Temperature).
5. Press the CHANGE key. The display will begin to flash.
6. Use the
▲ and ▼ arrow keys to select the desired building reference temperature.
7. Press ENTER to save any changes.
8. Next, scroll through the Configuration Menu until the display shows Reset Ratio.
Press the CHANGE key. The display will begin to flash.
9. Use the
▲ and ▼ arrow keys to select the reset ratio determined in step 5.
Press ENTER to save the change.
Refer to paragraph 2.2 for detailed instructions on menu changing.
5.3.4 Direct Drive Modes
The boiler’s valve position can be changed by a remote signal typically sent from an energy
management system. The Direct Drive modes are driven by current or voltage signals in the
following ranges:
• 4 - 20 mA/1 - 5 Vdc
• 0 - 20 mA/0 - 5 Vdc
The factory default setting is 4 - 20 mA/1 - 5 Vdc. In this mode of operation, a 4 to 20mA signal,
sent by an energy management system, is used to change the boiler’s valve position from 0% to
100%. The 4 mA/1Vdc signal is equal to a 0% valve position while a 20 mA /5Vdc signal is
equal to a 100% valve position. When a 0-20 mA/0-5 Vdc signal is used, zero is equal to a 0%
valve position.