AAON MHGRV-X User Manual

9
MHGRV-X Field Technical Guide
INPUTS AND OUTPUTS
Inputs and Outputs
I/O Map
The following inputs and outputs are available on the MHGRV-X.
See Table 2, this page to reference the Input/Output Map.
NOTE: All analog and 24 VAC contact closure inputs are
used only in Stand-Alone operation.
Analog Inputs
SAT: Supply Air Temperature Sensor
Used in Stand-Alone operation and when MODGAS is connected
to a CAV/VAV or MUA controller. The Supply Air Temperature
Sensor is the main control input. This sensor has to be installed
for the unit to operate. The Supply Air Temperature Sensor is
located in the discharge air stream and monitors the HVAC unit’s
Supply Air Temperature to maintain the Supply Air Temperature
Setpoint.
RST IN: Reset Signal
Used only in Stand-Alone operation. The Discharge Temperature
Setpoint can be reset by supplying a 0-10 VDC signal to the
RESET IN low voltage terminal block. This reset signal is
optional and need only be used if you require resetting of the
discharge air temperature.
AUX IN: Auxiliary Reheat Valve Input
Used when AUX mode is congured as enabled. This input looks
at a 0-10 VDC signal to control the valve position.
• 0VDC = 0% Reheat Valve position
• 5VDC = 50% Reheat Valve position
• 10VDC = 100% Reheat Valve position.
Binary Inputs
REHEAT EN: Reheat Enable Contact
Used only in Stand-Alone operation. When a call for
dehumidification is initiated by another controller, this
interlocked 24 VAC wet contact closure is used to enable the
MHGRV-X.
HEAT OVR: Heating Override
Used only in Stand-Alone operation. When a call for heating is
initiated by the HVAC unit, this interlocked 24 VAC wet contact
closure is used to override the MHGRV-X Dehumidication
Mode.
COOL OVR: Cooling Override
Used only in Stand-Alone operation. When a call for cooling is
initiated by the HVAC unit, this interlocked 24 VAC wet contact
closure is used to override the MHGRV-X Dehumidication
Mode.
Relay Outputs
FAN: Fan Enable
When a call for Dehumidication, Cooling Override, or Heating
Override is received, this relay will be closed to energize the
HVAC unit Supply Fan.
CMP: Compressor Enable
When a call for Dehumidification or Cooling Override is
received, this relay will be closed to energize the Compressor(s).
VALVE: Flush Active Signal / Compressor 2
If congured as Flush, this relay will be active any time a Flush
Cycle is active. When the Flush Cycle ends this relay will turn
o until the next ush occurs.
If congured as Compressor 2, this relay will be used to control
a second Compressor when there is a call for Dehumidication.
Compressor 2 will come on 30 seconds after the rst Compressor
activates. Compressor 2 has a minimum run time of 10 minutes,
and will turn o if the Reheat Valve is at 100% and the Supply
Air Temperature is 5°F below setpoint for one minute. After
being o for 10 minutes, it can come back on if the Supply Air
Temperature is 5°F above setpoint and the valve is at 0%.
Table 2: MHGRV-X Inputs and Outputs
ANALOG INPUTS
1 Supply Temperature
2 Reset Signal
3 AUX Input
BINARY INPUTS
1 Reheat Enable
2 Heating Override
3 Cooling Override
RELAYS
1 Fan
2 Compressor
3 Flush Active Signal / Compressor 2
4 Auxiliary / Reversing Valve

AAON MHGRV-X Specifications

General

Brand	AAON
Model	MHGRV-X
Category	Controller
Language	English