Hello,

I’m not a builder or an HVAC contractor… just a homeowner.  I have a question about the insulation that’s inside the air handler, which is encased in metal. 

In 2018, we had a hurricane.  There was a lot of wind and water damage to the house, which required us to move out in 2019 to replace the ceilings, etc., and refinish the floors.  After the demo of the drywall, the air handler was removed from its closet and placed in a room of the house.  During this time, we smelled a terrible stench that we discovered was coming from the air handler.  Our HVAC service company did a “pull and clean” of the condenser (coil?) and that didn’t make a difference.  So then they took the air handler back to their shop and replaced the insulation inside the air handler.  That *did* work, and the stench was gone when the unit was put back in place.  

My question is, what would cause the insulation inside the casing of the air handler to become contaminated in such a way that it stank like that?  Air doesn’t flow through that insulation, correct?  Could it be the result of having the unit turned off long-term in a humid environment?  (Florida.)  Or is it possible it was caused by dusty/dirty air flow?  (The demo team was not supposed to have the unit turned on, but I can’t be sure they didn’t turn it on.)  We did not start to smell the stench until the unit was unhooked and being stored in another room.  I don’t have any photos of the insulation because they took the unit to their shop to do the work. 

I’m trying to get reimbursed for the re-insulation cost by my insurance company, but if it was most likely caused by dirty air flow, I would need to revisit that part of my claim.

Thanks in advance for any insight you can give.  

V/r,

cvd