40
MODGAS-XWR2 Technical Guide
Mounting the Supply Air Temperature
Sensor
The Supply Air Temperature (SAT) Sensor should be located
in the duct-work downstream of the unit supply air connection.
Locate the sensor in the center of the widest part of the duct.
Use the supplied template and a 5/16” drill to make a hole for
the sensor.
Install the gasket over the probe and mount securely to the duct
using the supplied sheet metal screws. Be sure the gasket is
compressed to provide an air tight seal.
For best accuracy, apply insulation on the outside of the duct,
over the sensor. This will help prevent thermal gradients from
affecting the sensor.
WARNING:
Ensure the Supply Air Temperature Sensor
is mounted and wired according to these
instructions prior to testing the unit or
else the modulating valve will not control
properly and may damage your equipment.
Stand-Alone Mode
In Stand-Alone Mode, the SAT Sensor is connected to the
MODGAS-XWR2. If, in Stand-Alone Mode, the MODGAS-
XWR2 is used in conjunction with a Stand-Alone MHGRV
module, the SAT sensor is shared between the two modules and
always attaches to the MODGAS-XWR2.
See
Table 10, page 32
for SAT Options Jumper Settings and
reference the appropriate figure for wiring. See
Table 9, page
41
for details about retrofit applications.
Communication Mode
When communicating with AAON unit controllers, the
SAT Sensor will be connected to the AAON unit controller.
The exception would be in retrofit applications with older
controllers. See
Table 11, page 39
for SAT Options Jumper
Settings and see the appropriate figure
for wiring. See
Table 9,
page 39
for details about retrofit applications.
NOTES:
1. Leads are non-polarized. Butt splice leads to 24-gauge wire minimum.
2. In Stand-Alone and retrofit applications, connect leads to
“SAT and “GND”
on MODGAS-XWR2.
3. If using a VCM-X, SA, RNE, or VCB-X Controller,
connect leads to
“AI2” and “GND” on main controller.
4. If using a VCCX2 Controlle
r,
connect leads to “AI3 and “GND” on
main controller.
Duct Work
Drill 5/16” hole for probe
Adhesive backed drill guide mounting template
Gasket
Mounting Plate
1/4” hex head sheet metal screws
Thread
Together
5-1/2” or 11-1/2”
depending on model
number
3/4”
4.0”
Figure 17: Supply Air Temperature Sensor Installation
APPENDIX A: SAT SENSOR
Installation
