Jandy LX Heater Flashback/Blowback Issue on Heater Startup

[smuggs]

I'm entering my third year with my pool in South Jersey. This year, I'm having a problem with my Jandy LX heater. It "flashes back" when attempting to start up. In the past 2 years, this happened once or twice as there were spider webs and the like in the venturis. This year, I attempted to clean any debris out with my air compressor after finding this flashback happening for more than a couple times.
The heater is still under warranty, but I am trying to understand what could be causing this so that the Pool Company doesn't just put a band-aid in place.

Thanks for your help

 

[Bama Rambler]

You've already discovered the most common issue, Spiders! :shaking:
Mud daubers will also build nests in the burner tube but I don't know if you have them up there.
Rust and debris is the next most common cause.
Since it's under warranty you might want to call them first, but I suspect spiders, nest or debris will not be covered.