How can I narrow down what component of our HVAC system is causing health complaints?
In addition/renovation project in CT, two Carrier high-efficiency forced air heat pump systems were installed. The original heating system (hot water) was completely removed and brand new ducts were installed throughout.
About six months after moving in, strange smells began to be circulated with the hvac system. Eventually, Carrier replaced coils on both units, which did help with funky smell. But something continues to be circulated whenever heat or air conditioning is on and is causing chest pain and pressure, shortness of breath, and itchy eyes. It was so bad that we actually had systems turned off for over a year and heated with only plug in radiant heaters.
Most recently, we had blower test performed with horrible results. Decided to go with aeroseal as best method to deal with such extensive leakage. Another blower test confirmed that the aeroseal did its job; yet, the health symptoms persist.
We are nearing the point of selling the home because we can’t live in it, but we are heartsick. This addition/renovation came on the heels of going through cancer treatments with a young child, as well as many moves over a short number of years. We intended to stay here for the duration and the thought of selling (likely at a substantial loss) breaks our hearts. There MUST be some way to fix this since it is so clearly related to the hvac system. Please help!
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Replies
Leslie,
When you turned off your HVAC system and used radiant heaters, did your symptoms go away?
When you refer to a "blower test," I'm guessing that you are referring to a duct tightness test (usually performed with a Duct Blaster). Is that the test you mean?
If your brand-new duct system was as leaky as you imply, the contractor who installed your system made an error. Is there any chance that they used panned joist bays instead of ductwork for some of the duct runs?
Yes to the first question. That's what has helped narrow it down to hvac system.
Yes to the second question.
Yes to the third question.
I should add that at first, we thought the smell from ducts was basement air, and maybe some of it was since that is not as noticeable now. The air blowing out of ducts doesn't smell fresh. I should also tell you that we had IAQ tests done over the summer, which indicated no mold problems.
Leslie,
National building codes do not permit the use of panned joist bays instead of ductwork. I think you can make the case that this was a contractor error, and that the contractor should return to your house and install ductwork (instead of panned joist bays) at no cost to you.
It's not unusual for framing bays to smell of rodent droppings. By all means, the first step is to correct the problem with the panned joist bays.
Interesting. I did not think panned bays were against code (though not a best practice). Will consider your advice--thank you so much for your help.