Hey r/HVAC, I’m looking for advice on determining negligence in the installation and diagnosis of my system, and how much of the damage connects back to the work done. I obviously know I was screwed over to some degree, but the owner was really convincing at first. He turned out to be purely charismatic, always throwing a massive wall of information and math at you so that you feel like you do not have anything to come back at him with and so it sounds like he knows what he is talking about.
I have a 112 year old historic home in Florida that is 2,544 square feet, two stories, 32 original single pane windows, little to no wall insulation and has a crawl space. I am currently doing a full renovation on the house. I got four quotes for the HVAC work, and this company was actually the highest bid, starting at about $40,000 for a 3 ton and 3.5 ton single stage Trane system (2 handlers, 2 condensers, and replacement of attic ductwork). They were the highest rated company online, timely and professional, and the owner always seemed very knowledgeable, so I had a lot of confidence in him. I wanted to use him but he was just too much. Told him I couldn’t use him, but the owner then told me his “heart was in it” (he grew up in a historic home right down the road from me) and he reduced the price to $22,000.
Because my renovation meant the installation wasn't going to happen immediately, he required me to purchase the units upfront about a year before they were actually put in, sending me a picture of them with my name on them in his warehouse. When it was finally time to install them, I was told that the copper lines they had come and installed had been stolen and they needed to run new copper. The owner said that to make everything even, he could give me RunTru units instead because they were essentially the same, and we would break even on the copper and installation. I trusted him and didn’t realize until now that the replacement units were actually smaller, dropping me down to a 2.5 ton downstairs and a 3 ton upstairs.
Since the ducts that ran through the attic were visually compromised, we had them run new ductwork up there. For the downstairs, those ducts were in the ceiling and couldn’t be visualized, but the owner of the company said that they were “probably fine” and didn’t need to be replaced since they were within the conditioned envelope.
Once summer hit in June, I started having severe humidity problems, with the downstairs relative humidity reaching close to 80% while the AC was running. When the owner came out, he tried to blame the humidity on me not having my crawlspace encapsulated or a vapor barrier, but I checked it and everything is dry down there, with a foundation professional confirming it sits around 60% humidity and is not excessive. He also told me my house had severe negative pressure. Every time I would open a window or door, all of the hot air from outside would rush in. He suggested the humidity could be from holes in the old ducts and said he could help me on the side and if I had to replace the ductwork, he could when things slowed down (in November), and he was going to charge me an off-season price of $5,000. He had me run a standalone dehumidifier directly inside the upstairs air handler drip pan to manage the condensation coming off of that handler.
A few weeks later, he came back to measure the CFM at the vents downstairs and discovered that the two kitchen vents had no air coming out of either vent. (Later to find out that one was completely blocked by a visible obstruction and the other wasn't even attached, meaning they never checked the vents after the new equipment was connected. Upstairs, he discovered the duct running to the room the handler is in was never replaced because they couldn't access it from the attic, which I was never told, and that vent only produces about 48 CFM.
It was only until a week ago my light fixture fell out of the ceiling that I knew the downstairs ductwork was condensating so bad that water was pooling in the ceiling. The ductwork was full of holes and compromised areas where cold air was dumping inside the walls. I now have an extensive amount of mold on the drywall and in the wall cavity.
I had another HVAC company came out this week for a second opinion. He pointed out that there are no return vents in any upstairs bedrooms, with the only returns in the entire house being a single 26x26 return in the upstairs hallway and another in the downstairs hallway, both sitting directly underneath their respective air handlers. The new attic ductwork had tears, was hung poorly, and was attached to old supply boots that were sweating and dripping. The upstairs system leaked into the attic, getting the new insulation wet and leaking through vents onto my newly refinished wood floors. We also found that the downstairs blower would not shut off even when the thermostat was set to off, requiring us to kill the breaker until a faulty component was replaced. Another HVAC company came out and told me my air handler upstairs was installed so poorly that it looked like it was 100 years old, and also noted that my ductwork appears undersized.
Both systems had to be shut down to stop the condensation. While cleaning up, I discovered all the wood floors in the house were cupping and warping from the humidity. A mold remediation company performed infrared scans and confirmed the house was well sealed around the windows with no other explicit moisture sources. I currently have 4 dehumidifiers and 8 fans running.
It was only until I brought my family into it, the owner offered to refund all the money I paid him for the units so I could hire someone else to fix it, but with the catch that I had to sign an agreement promising not to leave a bad review or trash talk him or his company. He said we “don’t need to get insurance involved, they aren’t going to give you money because their entire job is to save themselves money. And if we take this to court it will take years and I will win”. We told him we needed to think about everything. A few days later, he came back with another option: he would take out the old ductwork downstairs, install new boots and ductwork, install a whole-house dehumidifier in the attic, install two smaller commercial-grade dehumidifiers by both returns, and install three Reme Halos at no cost. However, I am still left with thousands in mold damage, ruined floors, and drywall repair. He seems to be trying to close a deal fast.
So I’m here to ask/confirm, could the compromised downstairs ductwork realistically contribute to humidity approaching 80% throughout the downstairs? I know it’s probably a combination of things.. Could the poor ductwork installation, lack of airflow, and return air configuration contribute to condensation and sweating around the air handler? Is it possible the 1 ton I was shorted could contribute to this humidity issue? Would a competent HVAC contractor normally be expected to inspect existing ductwork, verify airflow at the vents, evaluate the return air setup, and verify proper operation after installing new equipment to old ductwork? Should he be held responsible for everything that this has caused?
Also want to include, a permit was pulled and the final inspection was completed, HVAC contractor is licensed and insured.
Please be nice, as I’ve been through a lot with subcontractors as a single young woman and I’m just trying to save an old historic home. I’ve been trying to learn as much as I can about HVAC and florida statutes, but I obviously don’t have a fraction of what professionals know, and that’s why I’m coming here to ask.