Airstream PNEG-343 - Manual (Page 16)

16
DRYER PRE START CHECKS
FAN SWITCHES
purge delay of approximately 10
seconds. Gas pressure should be
shown on the gauge. At this time
adjust the burner hi-lo fire thermo-
stat to 200
°
F, causing the burner to
operate on hi-fire. This thermostat
is located on the front left side of the
dryer. Observe the gas pressure on
gauge, and turn the thermostat to its
minimum setting, causing the burner
to cycle into lo-fire. As the burner
thermostat is turned down the gas
pressure should also show a notice-
able drop, indicating that the hi-fire
solenoid is closed and the burner is
being supplied with less gas
through the low fire control valve.
At this time set the hi-fire and lo-
crease the speed. Make sure the
drive chain tension is properly ad-
justed and all sections of the meter-
ing rolls rotate. Turn the unload switch
off after these checks are complete.
The bottom auger will continue to run
for 30 seconds after the switch is
turned off to allow for cleanout.
Bump each fan switch and observe
the fan rotation. The fan should run
counterclockwise. Sometimes on
three phase models all motors will
run backwards. They can easily be
reversed by interchanging two of the
three power supply wires. Reverse
the two outside wires, L1 and L3,
and leave the middle one in the
same position.
Note: If the dryer is empty, the
fans or burners will not operate. The
fans cannot create enough static
pressure to engage the air switch.
You will receive a loss of airflow
message.
The dryer fan and heater controls featuring: 1-pressure regulator, 2-lo-fire
control valve, 3-high pressure solenoid, 4-low pressure solenoid, 5-hi-lo fire
thermostat, 6-fuel supply line, 7-LP solenoid or supply ball valve(NG),
8-air pressure switch and 9-liquid filled gauge.
fire pressure settings. Use the
pressure regulator for hi-fire and
the ball valve for lo-fire. The ther-
mostat should cycle between high
and low, approximately 4 to 5 times
per minute.
Approximate settings should be:
LP Gas Hi-Fire 6-15 lbs.
Lo-Fire 2-6 lbs.
Natural Gas Hi-Fire 6-10 lbs.
Lo-Fire 1-3 lbs.
If the burner remains on hi-fire
and does not cycle, increase the
regulator setting on the propane
models, or the supply valve on the
natural gas models in order to reach
the thermostat setting. If the burner
remains in lo-fire and does not cycle,
Test fire each burner by starting the
fan. Then, turn the burner switch to
on. Turn on the fuel supply, and the
burner should ignite after a short
BURNER TEST FIRE
To check the burner safety function, first
make sure the main gas valve is off. Turn
the fan switch on and allow the fan to
start. Then, turn the heater switch on
for that fan. The dryer will shut down
after 20 seconds. The safety message,
"Burner 1 warning flame not detected"
will appear. Restart dryer and repeat for
each fan/heater.
BURNER SAFETY
3
4 2
1
7
8
6
5
9