The indoor odor problem in our house was like death by a thousand cuts or a frog in a slow boiling pot. I don’t think we really noticed until is was so bad that we couldn’t even have people over. The house we live in was our first home purchase. It came with all the stuff we wanted in order for this to be our family house. And part of that was the new residential HVAC. The previous owner put in the new heating and cooling equipment just prior to putting the house on the market. So it was basically brand new when we got it. And we made sure to provide the HVAC unit with all the HVAC maintenance it needed. That was a great move since we had no problems ever with that heating and cooling equipment. But with kids, dog, cats and thousands of cooking experiments over the years, the house ended up really stinky. I think it hit my wife and I the most once the kids were out of the house and in college. We’d come home from the zone controlled HVAC of the office to a wall of odors. Of course, we tried all the deodorizers and scented candles but to no avail. Finally, when we had to replace the HVAC equipment after 25 years, we asked the HVAC professionals for help with the odor. And that’s how we got the whole home air purification system with our new HVAC unit. And our house is like heaven now. We have the best quality heating and air ever and the place smells so fresh and clean.