Greenheck Vari-Green Control - Constant Pressure Indoor (474766) - Manual (Page 7)

7
One of two things must happen for the system to
return to normal operating mode:
• The controller will sense when a dryer, bathroom
fan, etc. is turned on and will vary the exhaust fan
speed appropriately.
• If for some reason the system needs to be
manually awakened from cutout mode, hold the
Enter button for 5 seconds and the system will
return to normal operating mode.
If the controller will not shut the fan off, verify that the
cutout value is correct and that the timer has started
by looking for the flashing LED. If the flashing LED
is not displayed, then the cutout value needs to be
adjusted. Remember the cutout value should be set
when there is no demand on the system.
If the controller shuts the fan off when there is
demand on the system, the cutout value is too high.
Lower the value and observe the operation of the
system.
Cutout Delay Timer, Parameter P07
Factory Default = 30 seconds
0 to 100 seconds in 1 second increments
See parameter P06 for operational details.
Override Output Percent, Parameter P08
Factory Default = 100%
20% to 100% in 1% increments
During normal operation, when the remote override
switch is closed, the fan will immediately ramp
to P08% speed and stays there until the remote
override switch is opened. The override can be
activated by any normally-open voltage-free contact.
Closing the contact will activate the override.
The LED will turn red and the display will show Ovr
when the override switch is closed.
Pressure Input Filter, Parameter P09
Factory Default = 0 seconds
0 = No Filter
0 to 10 seconds in 1 second increments
Pressure filter time constant. Set higher than zero if
wind gusts interfere with stable operation.
Start Up Timer, Parameter P10
Factory Default = 10 seconds
10 to 30 seconds in 1 second increments
At power up, set the output to 2 VDC for the time in
parameter 10, then resume algorithm control.
Fan-Inlet/Fan-Outlet Control, Parameter P11
Factory Default = 1, fan inlet control
0 = Fan Outlet Control
1 = Fan Inlet Control
The controller has two major modes; controlling
pressure on the fan inlet, and controlling pressure on
the fan outlet.
Exhaust fans use inlet control. Supply fans use
outlet control. Inline fans may use either inlet or
outlet control depending on the location of the tap.
If controlling velocity pressure, set P11=0.
Wiring Diagram