Grain Systems PNEG-236 - Manual (Page 12)

12 PNEG-236 Humidistat-Thermostat
6. Operation and Service
High-Low Temperature Control
1. Turn fan unit ON and let it run 3 to 5 minutes to equalize temperature under the bin.
2. Rotate the thermostat knob clockwise to warmest position.
3. Open gas valves (including Low-Fire valve) to the heater and turn the heater ON. Set heater gas
pressure to a moderately high setting (5 to 10 PSI).
4. Monitor the thermometer on the thermostat housing. When the thermostat comes up to desired
temperature, slowly turn the most at knob counterclockwise until heater cycles to Low-Flame.
5. If the unit does not reach desired temperature, gradually increase the gas pressure until the
temperature rises to desired level.
6. Adjust the Low-Fire valve so that the temperature drops until the unit cycles back to High-Flame.
7. Watch the unit run through several cycles and make any final adjustments. (NOTE: The unit should
cycle approximately two (2) times per minute. If not adjust gas pressure.)
8. Significant changes in outside air temperature may require readjustment of gas pressure.
NOTE: If temperature of Low-Flame exceeds thermostat settings (above normal outside temperatures)
unit will cycle from Low-Flame to OFF. (Top dry units will shut down completely.)
Humidistat-Thermostat Service
GSI thermostats are designed and built to withstand the harsh conditions usually found in drying bins. A
yearly preventative maintenance inspection may extend the life of the heating controls many years.
1. Remove mounting screws from the thermostat housing and remove the housing from the bin wall.
2. Carefully remove the back panel from the housing. (It may be necessary to cut caulking.)
3. Blow out any dust or dirt that may have collected inside the housing.
4. Inspect the wiring for any loose connections, or rodent and insect damage.
5. Replace the back panel and caulk the corners to help seal the unit.
6. Reinstall the unit on the bin wall.
Figure 6A
Always disconnect and lock out power before working on or around heater.
The Airstream Humidistat-Thermostat is mounted
on the lower right side of the grain bin’s transition.
This allows for easy service and operation.