Dunkirk D247 Installation Instructions Manual page 22

IGNITION CABLE CHECK
Cable must not run in continuous contact with a metal
surface or spark voltage will be greatly reduced.
Connections to the stud terminal on the $8600 and on the
igniter-sensor must be clean and tight. Loose connections
may not conduct a flame current even though the ignition
spark is satisfactory. Check the electrical continuity of the
cable.
CHECK GROUNDING
A common ground is required for the pilot burner/
igniter-sensor mounting bracket, and the GND terminal of
the $8600. If the ground is poor or erratic, safety shutdown
may occur occasionally even though operation is normal
at the time of the checkout. Therefore, if nuisance
shutdowns occur, be sure to check the grounding.
STARTUP AND CHECKOUT
NOTE: If any component in the system fails, the system
will not operate. If the system does not perform as outlined
in Start System, below, refer to the $8600 Intermittent Pilot
System Trouble-shooting Table.
START SYSTEM
1. Turn on power to the $8600(s) and turn off gas supply.
2. Check $8600(s) operation as follows:
a. Set the Thermostat or controller above room
temperature to call for heat.
b. Watch for spark at the pilot burner(s). 3. Turn on
gas supply.
4. Set thermostat or controller above room temperature to
call for heat.
5. System should start as follows:
a. Spark will turn on and pilot gas valve will open at
once. Pilot burner(s) should ignite after gas reaches
the pilot burner(s).
b. Spark ignition should cut off when pilot flame is
established.
c. Main gas valve should open and main burners
should ignite after gas reaches the burner ports.
NOTE: Lightoff may not be satisfactory until the gas input
and combustion air have been adjusted.
WARNING
DO NOT OMIT THIS TEST
With main burners in operation, paint pipe joints, pilot tubing,
connections, screws, and valve(s) gaskets with a rich soap
and water solution. Bubbles indicate gas leakage. To stop
leak, tighten joints and screws or replace gaskets. Never
use a flame to check for gas leaks.
PILOT FLAME ADJUSTMENT
The pilot flame should envelop 3/8 to 1/2 inch of the tip of
the insulated rod on the igniter-sensor. If adjustment is
required, remove the pilot adjustment cover screw and turn
the inner adjustment screw clockwise to decrease or
counterclockwise to increase the pilot flame. Be sure to
replace cover screw after adjustment to prevent possible
gas leakage.
PROPER FLAME ADJUSTMENT
CHECK BURNERINPUT
Checkboiler_rproperBTUinputrate.
CAUTION
Do not exceed the Input rate stamped on the nameplate of
the boiler located on the End Jacket Panel.
Make certain primary air supply to the Main burners is
properly adjusted for complete combustion.
I WARNING I
If boiler is shut down for service, the gas and electric must
be off for 5 minutes before relighting.
To check boiler for proper BTU Input proceed as follows.
With main burners operating, measure the gas Input to the
boiler by reading the meter. Be sure all other appliances
connected to the same meter are shut off. Rate of gas flow
(cu. ft. per hour) multiplied by the BTU value of the gas
should check with the BTU Input shown on the nameplate
of the boiler. If it is within 5%, adjust Pressure Regulator to
obtain the desired flow (stem for adjustment is under the
cap in the top of the regulator). TURN CLOCKWISE TO
INCREASE INPUT AND COUNTERCLOCKWISE TO
DECREASE THE INPUT RATE.
NOTE: The adjustment screw is plastic and may require
slightly greater turning force than metal threads.
Be sure to replace Regulator Cap.
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