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Series
4.0
Operation
4.0
Operation
•
Sequence of Operation
Important! Before operating the heater, conduct the following safety procedures:
• Check for any possible gas leaks.
• Alert all persons about the hazards of high surface temperatures and to keep a safe distance away in
order to avoid burns and possible clothing ignition.
• Provide supervision when young children are in the area of the heater.
• Check to make sure clothing isn’t hung from the heater and that flammable materials are not
placed on or near the heater.
• Check that all guards or protective devices are in place and secure.
• Check the hose assembly for excessive abrasion, wear, or damage. Replace if necessary.
• Check control compartment, burners, and circulating air passages for debris. If necessary, clean the
debris.
Pre-Commissioning Check
Inspect ceramic plaques to ensure that none have been damaged. If any cracks are detected, the heater
must not be commissioned until the affected burner unit has been replaced (see section 5.0
Maintenance).
If compressed air is used to detect leaks in the gas supply line, disconnect and cap the ball valve to avoid
damage to the regulator and gas valve.
Sequence of Operation
Starting Circuit:
When voltage is applied to the controls connection, the ignition module sends power to the gas valve
while simultaneously sending spark to the igniter. The ignition time is 15 seconds. Once the flame on the
burner is established, the ignition module will continuously monitor the flame. The heater will continue to
run as long as there is 230 V present in the call for heat. If the heater does not light on the first trial, the
heater will attempt two more ignitions prior to going into a lockout mode.
Running Circuit:
After ignition, the flame rod monitors the flame. As long as a flame is present, the valve is held open. If the
flame is lost, the control acts to close the valve within one second, and a new trial sequence identical to
that at start-up is initiated. If proof of flame is not established within the 15 second trial for ignition, the unit
will retry two additional times before entering lockout mode. If lockout occurs, the control can be reset by
briefly interrupting the power source.
WARNING
!
Improper operation of the heater may result in explosion, fire,
shock, and carbon monoxide poisoning. Follow all guidelines and
warnings in this manual and relevant applicable codes. Always
conduct safety checks before operating the heater. Do not operate
the heater in unsafe conditions.
