DVS -30-2 - Manual (Page 34)

Page 34 13369-1-0203
POWER INTERRUPTION
System shuts off. Restarts when
power is restored.
PILOT FLAME FAILURE
Second main operator closes.
Module starts trial for ignition.
Spark Generator Powered
First Valve (Pilot)
Operator Opens
Pilot burner lights.
Module senses flame current.
PILOT BURNER OPERATION
MODULE
S8600H
* Lockout timing is stamped on module.
RESPONSE
After 90 seconds*pilot valve
closes, spark stops.
OR
IF FLAME CURRENT SENSED
• Spark generator off.
• Second valve operator
(Main) opens.
MAIN BURNER OPERATION
Module monitors pilot
flame current.
THERMOSTAT SATISIFIED
Valves close.
Pilot and main burners
are off.
START
STAGE 1
Trial for Ignition
STAGE 2
Main Burner
Operation
END
S8600H NORMAL OPERATING SEQUENCE
Pilot burner does not light
Thermostat, Wall Switch,
Remote, Etc. Calls For Hea
t
If the pilot does not light, or the pilot flame current is not at
least 1.0 uA and steady, the module will not energize the
second main valve and the main burner will not light.
Safety Lockout
S8600H provides 100 percent shutoff, or safety lockout. A
timer starts timing the moment the trial for ignition starts.
Ignition spark continues only until the timed trial for ignition
period ends. Then the module goes into safety lockout.
Lockout de-energizes the first main valve operator and closes
the first main valve in the gas control, stopping pilot gas flow.
The control system must be reset by setting the thermostat
below room temperature for one minute or by turning off
power to the module for one minute.
Main Burner Operation
When the pilot flame is established, a flame rectification
circuit is completed between the sensor and burner ground.
The flame sensing circuit in the module detects the flame
current, shuts off the spark generator and energizes the second
main valve operator. The second main valve opens and gas
flows to the main burner, where it is ignited by the pilot burner.
The flame current also holds the safety lockout timer in the
reset (normal) operating condition.
When the call for heat ends, both main valve operators are de-
energized, and both main valves in the gas control close.
CAUTION: Label all wires prior to disconnection when
servicing controls. Wiring errors can cause improper and
dangerous operation. Verify proper operation after servicing.
DVS-36 & DVS-42 INTERMITTENT PILOT TROUBLESHOOTING