DJM2.4 MANUAL
29 Oct 00 R2
casing to the mounting screw near the spark connection, or through the back of the case.
Mount the ignition control off the wall on insulated spacers and do not install a mounting
screw next to the spark wire location.
4. Check the resistance of the flame and spark rod to the wire connector terminal on the rod.
This should not exceed 2-ohms. If it does, replace the assembly.
5. Ensure that the ignition control and its transformer secondary are both adequately
grounded. If there is not an adequate ground then there will be a weakened flame rod
signal.
6. Some extreme cases of airborne electrical noise a special sheathing is available to shield
heavy ignition spark wire. Please consult factory. It may be necessary to install a ground
wire from burner ground terminal to chassis. Scrape the paint on chassis.
7. Spark gap should be set at 1/8 inch.
8. Check for cracked porcelains on the spark and flame rods. These have been found to be
cracked in the area where they pass through the mounting plate also. You cannot see into
this area and you can even have it feel tight. (If possible it may be best to check it with an
ignition device.)
8. Ensure there are no burrs or dirt in the pilot line orifice and air tube. These items have often
been found with dirt, rust, insulation, paper, etc., blocking them. This includes checking the
short connector at the blower housing where the rubber tube attaches. Also ensure no
capacitor mounting screw is blocking the inlet to the pilot tube.
9. Usually changing the pilot assembly will not have much of an affect on the pilot signal if
both assemblies are in good condition and installed correctly.
10. Ensure the pilot assembly gasket is tightly installed to stop air leakage into the pilot area.
11. Standard (round) burner only. If the burner plate is not centered in the hole, it may allow
too much of a gap over the top of the burner, thus increased airflow through the larger
opening may roll onto the pilot box. Place a spacer under the burner plate to raise it into a
centered position.
12. Due to the low capacities of some small units with standard (round) burners only, there may
be too much air entering into the pilot air tube. It may be necessary to reduce this air
quantity by placing a screw through the side of the combustion blower outlet in a manner
that the screw also passes through the metal tube that the rubber hose connects to. This
normally only occurs on units with an input of less then 300,000 BTUH. Some units have a
screw mounted capacitor, ensure the screw does not obstruct the pilot tube’s air path.
13. If a BMS signal is applied, caution should be taken about removing the transformer grounds
that may interfere with the BMS signal. It is possible that you may have disconnected the
ignition control or ignition transformer ground.
14. Water and ice have been located in the pilot gas lines, in the pilot air tube, in the pilot box,
and in the pilot gas orifice. Ensure these areas are free of moisture, locate the source and
correct it.
15. Snow, ice, or water on the ignition control(s) can stop a pilot from igniting or proving. These
devices and their associated parts must be kept clean and dry.
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