35
MODGAS-X Technical Guide
Replacing the MODGAS II with the
MODGAS-X
The retrofit replacement involves a few easy steps. Refer to
Figure 13, this page
.
WARNING:
Do not connect power to VOUT/Ground
terminal block.
Stand-Alone Mode Operation
Step 1:
Disconnect power from the MODGAS II Module.
Step 2:
Disconnect the Supply Air Temperature Sensor from
the MODGAS II and wire it to the MODGAS-X. If the
Supply Air Temperature Sensor is being shared with
a Stand-Alone MHGRV Module, maintain the same
wiring with the MHGRV Module.
Step 3:
Wire other inputs and outputs per
Figure 2, page 8
.
Step 4:
Set the SAT Options Jumper per
Table 11, page 34
.
Step 5:
Connect power to the MODGAS-X Module.
Communications Mode Operation
Step 1:
Disconnect power from the MODGAS-X Module.
Step 2:
The Supply Air Temperature Sensor needs to remain
installed on whatever controller or module it is currently
on. If it is currently installed on the MODGAS II
module, then reinstall it on the MODGAS-X.
Step 3:
Set the SAT Options Jumper per
Table 12, page 34
.
Step 4:
Connect power to the MODGAS-X.
I C cable connects to
AAON unit controller’s
expansion port
2
See
for
Jumper Settings.
Only one Supply Air Temperature
Sensor can be used per application.
SAT OPTIONS Table
18-30 VAC
GND
Supply Air
Temperature
Sensor
Mount in unit
supply air duct.
Note:
1. 24 VAC must be connected so
that all ground wires remain common.
2. All wiring to be in accordance with
local and national electrical codes
and specifications.
MODGAS-X
AAON P/N: ASM01668
LABEL P/N:
G041210
E-BUS
CONNECT
I2C
CONNECT
+24
V
A
C
GND
CONTACT RATING
@ 24 VAC
IS 1 AMP MAX
VOUT
GND
GAS VALVE
TERMINALS
COMM
RELAY OUTPUT
TERMINALS
INPUT TERMINALS (TYPE)
HEAT EN (BI)
AUX. (BI)
GND
RESET IN (AI)
SAT IN (AI)
GND (AI)
GND
AUX. (AI)
AUX 1
LOW SPEED
FAN
AUX 2
40 VA transformer
minimum
Line
YS102378 REV 1
Figure 13: MODGAS-X Module
APPENDIX B: MODGAS II REPLACEMENT
MODGAS-X Replacement of MODGAS II
