AAON MHGRV-X User Manual

29
MHGRV-X Field Technical Guide
Q: Are my valves wired correctly?
A: Both valves per circuit should be wired to the same terminal
block.
A: The Condenser Valve should be wired (from top to bottom)
BLACK, WHITE, RED, GREEN.
A: The Reheat Valve should be wired (from top to bottom)
BLACK, WHITE, GREEN, RED.
Q: How do I conrm the expansion module is
operating in Reheat (Dehumidication) mode?
A: Make sure the enable signal is activated by conrming that
the ENABLE LED is on.
A: Make sure the COMM LED is blinking.
A: Compare the Valve Position displayed on the MHGRV-X
screen with the number of STATUS LED blinks.
A: If all three things above are true, then the valve is operating
correctly in Reheat mode.
Q: Are the communications wired and congured
correctly?
A: For the MHGRV-X operating as Stand-Alone,
the following should be true:
1. The MHGRV-X is connected to the Reheat Expansion
Module with an E-BUS cable and the connections
are secure.
2. The MHGRV-X must be congured as S/A LOCKED
in the MHGRV-X Conguration Screens. To conrm
this, press the ENTER key once from the main screen.
It should display S/A MODE LOCKED.
3. The MHGRV-X must be congured for EXP VLVS
ENABLED in the MHGRV-X Conguration Screens.
If this is true, the COMM LED on the MHGRV-X
will blink once every second.
A: For the MHGRV-X operating with a VCCX2/
VCB-X, the following should be true:
1. The VCCX2 or VCB-X, MHGRV-X, and Reheat
Expansion Module are connected to each other with
an E-BUS cable and the connections are secure.
2. The MHGRV-X must be configured as S/A
AUTODECT in the MHGRV-X Configuration
Screens. To conrm this, press the ENTER key once
from the main screen. It should display COMM
MODE.
3. The MHGRV-X must be congured for EXP VLVS
ENABLED in the MHGRV-X Conguration Screens.
If this is true, the COMM LED on the MHGRV-X
will blink once every second.
Q: How do I change congurations for the valve
expansion modules?
A: Congurations will always match how the
MHGRV-X is congured. The congurations are
as follows:
1. Valve Size (hidden screen conguration)
2. Cooling Flush Time (setpoint screens when Stand-
Alone)
3. Reheat Flush Time (setpoint screens when Stand-
Alone)
4. Reheat Flush Reset Position (cannot be changed
by user)
APPENDIX C: REHEAT EXPANSION MODULE
Troubleshooting

AAON MHGRV-X Specifications

General

Brand	AAON
Model	MHGRV-X
Category	Controller
Language	English