31
INITIAL STARTUP
To set modulating valve at the start of the drying season:
NOTE: The valve and heater were tested at the factory and pre-set to as close to 120 degrees as allowed
in relation to that day’s current ambient temperature. You still need to adjust gas pressure and modulating
valve to reach your desired range for your crop. Determining this is your responsibility.
1.
Remove control panel lid and identify the modulating valve T-handle. Turn handle clockwise (this
maybe counter-clockwise if standing in front of the heater controls as the valves inlet and output are
mounted in the vertical location.) thus opening the valve.
2.
Start fan and heater according to separate instruction in respective manuals. There will be a 45
second delay as the fan purges the heater of any fuel vapors.
3.
Red light located on heater control panel comes on.
4.
Unlock locking nut on heater regulator. Adjust gas pressure to achieve the maximum desired burning
rate (reference gauge pressure).
5.
Adjust plenum temperature to desired level by turning T-handle on valve clockwise to increase fuel,
counterclockwise to decrease fuel. Continue to monitor plenum thermometer for desired temperature.
NOTE: Valve reaction time may be slow so allow temperature to stabilize to a balanced condition
before measuring temperature.
6.
Once desired temperature has been reached, and valve is fluctuating to satisfy it, lock locking nut on
regulator.
7.
Whenever shutting down your fan & heater system, always close the fuel source at the tank, draining
the lines, allow the heaters safety system to detect no flame and lock itself out.
8.
AFTER STEP 7 HAS BEEN COMPLETED- turn the heaters panel power switch to the off
position. Then shut down the fan.
TROUBLE SHOOTING GUIDE
Heater Will Not Fire:
Check heater regulator to determine a gas flow is available and the fuel source valves are open. On LP
units- check valve on lower manifold to be sure it’s in the open position.
Check all high limit switches (see Fig.2, page 37) to be sure they are closed. Press the red button located
on each high limit to insure they are engaged. There are three high limit switches located on all LP liquid
heaters and two on all super-low vapor units.
If the heater still will not fire, the problem may not be related to the modulating valve. Review the trouble
shooting guide on pages 33-35.
