Thanks for posting those links.
I’m going to pull the fuse out of my Phenomenal Aire bipolar ionization unit today and see if there is any change in the VOC levels in my encapsulated crawl space. (I have an Awair Element Indoor Air Quality Monitor currently in the crawl space and when the HVAC, a downflow unit, kicks in under heating or cooling, the VOC levels spike.) Today, the crawl space VOC levels rose from 93ppb to 850ppb when the HVAC kicked on under heating. Under cooling, the VOC levels can climb to 2,500ppb or higher. I don’t know if this is a result of our living space air mixing with the crawlspace air or if something in the supply line is causing the spike. I’ve read that an increase in temperature and humidity will also cause more VOCs to be released, but I wouldn’t expect that result to be immediate. Of course, this air quality monitor is a $150 device, so maybe the spike has something to do with the way this unit senses VOCs.
The ionizer is located: Filter >>> Coil >>> Fan >>> Ionizer>>>Supply Line in crawl space
Once the VOCs spike, they tend to remain elevated until fresh air is introduced (opening the crawl space door) or once the HVAC has remained off for hours.
I have a Santa Fe dehumidifier in the crawl space and keep the relative humidity averaging 51%. The temperature is a near-constant 69 F.
If pulling the fuse on the ionizer doesn’t shed any light on the situation, I guess my next step would be to install an ERV, but I would love to figure out a passive solution over adding another mechanical patch.
-Frank
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