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Figure 36 - Modulating Valve and Controls
Low-Fire Burner Adjustment
1. Lock the unit into low fire mode. This is achieved by configuring low fire by going into the HMI’s
configuration, go to:
Service > Test Menu > Test Gas Heat > Run Low Fire Test
.
2. Press and hold button #2 on the modulating valve until the LED light blinks red. Release the button.
The valve is now in low fire setting mode.
3. Press button #1 to increase flow or press button #2 to decrease flow.
- The desired pressure reading for natural gas is
0.15 in. wc
If this cannot be obtained, set the low fire
pressure as low as possible.
- The pressure reading for propane gas should
be
0.75 in. wc
4. Save the low fire setting by simultaneously holding down buttons #1 and #2 until the blinking LED turns
off. Press the abort button on the HMI to exit low fire mode.
Final Start-Up Procedure
1. With the air and burner systems in full operation and all ductwork attached, measure the system
airflow.
2. Once the proper airflow is achieved, measure and record the fan speed with a reliable tachometer.
Caution - Excessive speed will result in motor overloading or bearing failure
.
Do not set fan
RPMs higher than specified in the maximum RPM chart
.
3. Measure and record the
voltage
and
amperage
to the motor and compare with the motor nameplate
to determine if the motor is operating under safe load condition.
4. Check for any obstructions, tools, or hardware that may cause damage when unit is in full operation.
5. Make sure all access panels are in place and secure.
BUTTON 1
BUTTON 2
DIP SWITCHES
LED DISPLAY
