Ionizer in HVAC duct

[SHOZ]

I had my furnace replaced three years ago and had a chance to see inside the main duct. I was expecting the usual brown oil fuzz like in the return duct. Had been contemplating a duct cleaning service and in fact called one and they took one look at the crawl space and reneged.

But I was surprised to find them quite clean and not even much to wipe down. Ducts had been there for over 30 years. I'm guessing I bought the filter in the mid 80's and had the main duct replaced, water heater, AC unit and new oil furnace near the same time.. When I had the new furnace installed three years ago they didn't know what it was and questioned my wanting it left in place.

This is what the interior cell looks like, looks like Electro-Aire was the manufacturer for Sears. Thing weights about 20 lbs.

 

[PandaBear]

I would imagine UV works by killing mold on the water tray in the heat exchanger of an AC. Ionizer may help you clean the air but you already have a filter, it will likely only help a little (need to be very powerful to do anything for the amount of air you are moving) and it will likely not ionize the mold on the water tray or heat exchanger. You are probably better off with UV lamp still for mold control, and change your air filter often and with a better filter, and maybe a few more standalone HEPA filter inside the house.