Electronic Ignition Control/ Ignition Module - A.O. Smith BTR 120-400 Service Handbook

ELECTRONIC IGNITION CONTROL/ IGNITION MODULE

Each heater is equipped with a Honeywell ignition module. The solid state ignition control ignites the pilot
burner gas by creating a spark at the pilot assembly. Pilot gas is ignited and burns during each running cycle.
The main burner and pilot gases are cut off during the OFF cycle. Pilot gas ignition is proven by the pilot
sensor. Main burner ignition will not occur if the pilot sensor does not first sense pilot ignition.
Continuous Retry for Ignition
90 second trial/ 5 minute off.
Before calling your service agent, the following checklist should be examined to eliminate obvious problems
from those requiring replacement or servicing.
• Check that "main manual gas shut-off valve" is fully open and that gas service has not been interrupted.
• Check that after following the water OPERATING INSTRUCTIONS, the "Top Knob" of the gas control
valve is in "ON" position.
• Check electrical supply to the water heater for possible blown (or tripped) fusing or power interruption.
• Is the water temperature in tank below the thermostat dial setting on the thermostat (calling for heat)?
• It is possible that the high limit (E.C.O.) has functioned to shut off the water heater. Contact your
serviceman if limit continues to function to shut off water heater.
12 Servicing should only be performed by a Qualified Service Technician
Spark Connection
LED Indicators