Orion System MHGRV-X - Manual (Page 19)

MHGRV-X Field Technical Guide
APPENDIX B
19
Appendix B - MHGRV-X Replacement of MHGRV II
Replacing the MHGRV II with the
MHGRV-X
The drop-in replacement involves a few easy steps. Refer to Figure 7.
STAND-ALONE MODE OPERATION
Step 1: Disconnect power from the MHGRV II Controller.
Step 2: Disconnect the Supply Air Temperature Sensor from the
MHGRV II and wire it to the MHGRV-X. If the Supply
Air Temperature Sensor is being shared with a Stand-
Alone MODGAS Controller, maintain the same wiring
with
the MODGAS Controller.
Step 3: Separate the HGR Valve wires and the Condenser Valve
wires onto the appropriate Reheat Drive and Condenser
Drive
terminal blocks per Figure 3, page 6. Wire all
other inputs and outputs per Figure 3, also.
Step 4: Set the SAT Options Jumper per Table 8, page 18.
Step 5: Connect power to the MHGRV-X Controller.
COMMUNICATIONS MODE OPERATION
Step 1: Disconnect power from the MHGRV-II Controller.
Step 2: The Supply Air Temperature Sensor needs to remain
installed on whatever controller it is currently on. If it
is currently installed on the MHGRV II Controller, then
reinstall it on the MHGRV-X Controller. If it is currently
installed on the main unit controller or on a connected
MODGAS Controller, it needs to remain there.
Step 3: Set the SAT Options Jumper per Table 9, page 18.
Step 4: Connect power to the MHGRV-X Controller.
Figure 7: MHGRV-X Controller
Line
GND
24V
AC
40 VA
Transformer
Minimum
Supply
Air Temperature
Sensor
Mount In Supply
Air Duct
MHGRV-X CONTROLLER
(OE377-26-00059)
See Tables 7, 8 & 9 On Page 18 For
SAT OPTIONS Jumper Settings.
Only One Supply Air Temperature Sensor
Can Be Used Per Application.
I C Cable
Connects To
AAON Unit Controller’s
Port
2
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.
Connect To MHGRV-X Controller
In Stand-Alone Mode Or When
Using VAV/CAV Or MUA Controller.
If Also Using A MODGAS Controller
In Stand Alone Mode,
The SAT Sensor Connects
To The MODGAS Controller.