Dexter Laundry T-80 Reversing (On-Premise) - Manual (Page 9)

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exceed the equivalent of 20 feet and two elbows. The diameter of the main
discharge duct at the last dryer must be maintained to exhaust end.
NOTE: A small diameter duct will restrict airflow; a large diameter duct will reduce air
velocity; both contributing to lint build up. An inspection door should be
provided for periodic clean out of the main duct.
8. DRYER IGNITION (SOLID STATE IGNITION). The solid state ignition system lights
the main burner gas by spark. The gas is ignited and burns only when the gas-valve relay (in the
electronic controller) calls for heat. The procedure for first-time starting of a dryer is as follows:
A. First, review and comply with the “Warnings About Use and Operation” found on the
inside front cover of this manual. Be sure the electrical power supply is connected correctly.
This dryer MUST operate on 3 phase power. The dryer MUST be properly grounded. Connect
the ground lug to a good external ground.
B. Make sure all gas supply lines are purged of air, close the main gas shut-off valve and
wait for five minutes before turning the valve back on.
C. Turn on main electrical power switch, close loading door, use manual mode to set the
cycle time, and actuate the dryer by pushing the start button.
D. Natural gas and liquefied petroleum gas fired dryers both operate in the same manner.
When the temperature is below the cycle set point (indicating a demand for heat), the solid state
ignition control will automatically purge the supply for the first 10 second. After this purge, the
solid state ignition control will automatically supply energy to the spark gap and to the redundant
gas valve. Spark will continue until a flame is detected by the sensing probe, but not longer than
10 seconds. If the gas fails to ignite in 10 seconds the gas valve closes. It is then necessary to
interrupt electrical power to the ignition system before making another attempt at lighting the
burners. This can be done by opening the dryer door and allowing the dryer to come to a stop for
15 seconds, then closing the door and pushing the start button. The dryer will then repeat the
ignition trial cycle.
9. MAIN BURNER ADJUSTMENT. The primary air shutter of each main burner must be
properly adjusted for the correct air-gas ratio. Adjust the shutter by closing it sufficiently to give
a blue flame with a yellow tip. Next open the shutter until the yellow tips are at a minimum.
Securely lock each shutter in position by tightening the screw after adjusting the shutter.
DRYER SHUTDOWN
1. SOLID STATE IGNITION MODELS. To render the dryer inoperative turn off the main
gas shut-off valve and disconnect power to the dryer.