44
19.2
PILOT BURNER
Turn the pilot firing valve to off position and allow the appliance to try for ignition. Observe the spark
making sure that it is strong and continuous.
If the spark is not acceptable the igniter will have to be adjusted. This can be readily accomplished after
removing the main burner.
The spark gap should be 1/8” to 3/16”. Make sure that the electrode does not appear overheated or
fouled with carbon. It may be necessary to clean the ignition electrode using steel wool. Once the pilot
appears to be properly set, reinstall it into the appliance making sure to properly tighten the pilot line
connection.
If the pilot is removed from the main burner in the course of servicing the appliance, it is important to
reinstall it so that there is no gap between the top surface of the pilot tube and the underside of the metal
filter support screen. When properly set it will not be possible to slip a business card between the pilot
burner and the support screen. Figure 25 shows the burner box assembly with the metal filter cover
removed to expose pilot tube.
Figure 26: Pilot and Burner Box
Once the spark is satisfactory, open the pilot gas and allow the pilot burner to light. Once air has been
purged from the pilot line, the pilot flame should appear almost instantly at the initiation of spark. Cycle
the pilot several times to confirm reliability. A properly set pilot will appear blue and will engulf the igniter
and ground electrode.
Open the firing valve and allow the main burner to light. The pilot must not extinguish. After running for 15
minutes, cycle the appliance to ensure that the pilot remains stable.
20
OPERATION AND SERVICE
20.1
PRE-START CHECKLIST
Before operating the boiler, the entire system must be filled with water, purged of air and checked for
leaks. Do not use Stop leak or other boiler compounds. The gas piping must also be leak tested.
Any safety devices including low water cutoff, flow switch and high limit used in with this boiler must
receive periodic inspection (every six months) to assure proper operation. A low water cutoff of the float
type should be flushed every six months. All relief valves should be inspected and manually operated
every six months.
