Greenheck IGK (472084) - Manual (Page 9)

9 Model IGK Make-Up Air
®
Start-Up - Furnaces (all units)
IMPORTANT
For the unit to function properly, all valves must be
set for high and low fire.
NOTE
To force the unit to light for set-up purposes, the
heat switch must be closed or jumpered out. See
the Ladder Diagram on the inside of the control
center door for proper terminals to jumper out.
NOTE
If the unit is equipped with an independent
inlet air sensor (not incorporated into the stage
or modulation controller), the unit will not light
unless the outside air temperature is less than
the inlet air sensor setting. If the outside air is
greater than the inlet air sensor setting, turn the
setting to its maximum position. When set-up is
complete, reset the inlet air sensor to the proper
temperature. If the unit is equipped with a stage or
electronic modulation controller that includes an
inlet air sensor function, the inlet air sensor will be
overridden when the unit is forced to high fire.
Available Control Options
Single Furnace Units
2:1 Staged one 2-stage furnace
Start-Up - 2:1 Staged Control
1. Send Unit to High Fire
Send the unit to high fire by setting
the temperature selector to its
maximum setting.
2. Check the High Fire
Manifold Pressure
Using a manometer, measure the burner manifold
pressure at the manifold pressure test port. Refer to
the Gas Train Layout in the Reference section for the
test port location.
The pressure on high fire should be 3-1/2 inches wc
for natural gas and 10 inches wc for LP gas.
If needed, use the high fire adjustment screw on the
combination gas valve to adjust the high fire manifold
pressure. Counterclockwise rotation will decrease the
gas pressure and clockwise rotation will increase the
gas pressure.
3. Send Unit to Low Fire
Remove and isolate the wire from the high fire terminal
on the combination gas valve to send the unit to low
fire.
4. Check the Low Fire Manifold Pressure
Using a manometer, measure the burner manifold
pressure at the manifold pressure test port. Refer to
the Gas Train Layout in the Reference section for the
test port location.
The pressure on low fire
should be 7/8 inches wc
for natural gas and
2-1/2 inches wc for
LP gas.
If needed use the low fire adjustment screw on the
combination gas valve to adjust the low fire manifold
pressure. Counterclockwise rotation will decrease the
gas pressure and clockwise rotation will increase the
gas pressure. Once the low fire manifold pressure is
set, reattach the high fire wire to the high fire terminal.
5. Reset the Temperature Setting
Reset the temperature setting on the temperature
selector to the desired setting.
High Fire
Adjustment
Low Fire
Adjustment
High Fire
Terminal
Two Stage Manifold
Pressure (inches wc)
Natural Gas LP
Low Fire 7/8 2-1/2
High Fire 3-1/2 10
Temperature
Selector