I went through the fault history and have all Main Ingitition Failures and the 3rd one was No pilot sensed.
Then you likely have a flame rectification sense problem or your heat exchange is leaking and drowning the flame.
Could be a loose ground, bad high tension wire, sooted pilot, loose pilot, Check to make sure that the ground down by the pilot assembly is OK.
Check there is no corrosion around the pilot assembly.
Burner won't fire... Corrective action taken: All safety switches operate, I disconnected them and jumpered the wires getting an error when open and no error when jumped roll over switch works, error when open, no error when jumped or connected. Spark at pilot and it lights fuse on main board...
www.troublefreepool.com
Here is the manual for your heater:
http://cdn.globalimageserver.com/FetchDocument.aspx?ID=c404f1c5-ac50-4209-9457-56246d010b20. Look at page 34. If you do not have a millivolt system look at the bottom pilot assy. . Start cleaning by turning off heater and and gas supply shut off. Remove pilot bracket screw and green ground wire at bottom right of burner manifold bracket. Remove pilot tubing at gas valve. Remove pilot assy. and pilot tubing as one piece. Clean all metal pieces where pilot assy. bracket was attached to the burner manifold bracket including the screw and the metal termination of the green wire with a small stainless steel wire brush and/or small diamond file (available at Harbor Freight). On the pilot assy itself (page 34) you need to clean the underside of the pilot hood (above the pilot tubing attachment) with a dental pick (Harbor Freight) until the metal is clean. Also gently clean the spark rod with a small diamond file or steel wool all the way around to get bare metal, being careful to support the ceramic insulator so that it doesn't crack. Clean the underside of the ground hood ( opposite the pilot hood with the 2 extended tabs on the outside edges) with small stainless brush and/or diamond file to get to bare metal. Clean any screws and metal points of attachment at the grounding hood side of the pilot assy. at the pilot bracket and burner frame that the pilot bracket is attached to. Reassemble in reverse order making sure to tighten the pilot tubing to the gas valve. Turn on gas shut off and power to heater. Put a small amount of dawn dish detergent mixed with a little water on the pilot tubing attachment at the gas valve. Fire up heater. Check for any bubbles at pilot tubing attachment at gas valve (indication of a leak).
What does the Flame Strength indicator show on the Service Menu?
Service Menu and Fault History
To access the Service Menu and fault history,
press the MODE and UP buttons simultaneously for 3 to 5 seconds. The heater will continue to operate normally while in the Service Menu. The first screen displayed is the Flame Strength indicator, which indicates the pilot flame current using a bar graph and numerical display. A signal of less than 4 indicates a weak flame signal and may require service. Refer to Section 5 Troubleshooting in the manual for possible causes and corrections.
Press the DOWN button. The Supply Voltage screen indicates the voltage supplied to the control board. Normal readings range from 24 to 29 volts.
Press the DOWN button. The Run Time indicates the total hours of operation for the pool heater, as measured by the amount of time that the main gas valve has been powered. The Cycle count indicates the number of on/off cycles of the heater, as measured by the number of times the pilot valve has been powered.
Press the DOWN button. The Fault History can display up to ten faults in memory. The order of the faults begins with “Fault Last,” which is the most recent fault, and proceeds through ten most recent messages in chronological order. The second line of the display shows the fault message. If there are no faults in the history buffer, the second line reads “All Faults Clear.”
I am a novice but in the 406A manual it says on trouble shooting Under "Heater going off and on continuously" that could be External Bypass setting is out of adjutment ( solution adjust bypass) and also "Pressure switch out of adjustment... (solution adjust pressure switch). Are those things difficult to do and or do you think these could be the problem?
No, those are not likely to be the problem