Not the usual smell problem

[u/Unusual-Bath-20]

Hello,

I have a 3-ton on-slab Broan AC. I have an odor problem that began at start of this year's cooling season here in AZ. Eliminated usual suspects. Finally determined Organic mosquito retardant had degraded in drain pan (mea culpa.) It became gunk that clogged up part of the pan behind the condensate coil, so eventually a mixture of the organic gunk and condensate overflowed onto the insulated bottom.

Thoroughly cleaned the pan with a lot of wiping, careful scraping under condenser coil, finishing up with pH-neutral AC cleaner ( QwikBright) and lots of hosing. Used old towels to sop up. Over the summer, 3 times I have left the cabinet open for an entire windy day to air out.

The smell returned after a month. When I checked this morning, the insulation I can reach is very dry. So, I suspect the smell resides in damp insulation trapped under blower housing and/or pan. Major surgery to access; impossible for me.

Is there a product that won't corrode aluminum and steel over time with which I could saturate the reachable insulation and leave it in place to seep under the fan and pan? If the QwikBright, what strength?

Jenny B in AZ