You would believe that an weird and unwelcome smell would be a thing of the past with an indoor air cleaning system, but still, there was an unpleasant stink in the house. I tried using an air freshener, but it only worsened matters. The next morning I came with the air cleaner that I usually kept in the office, but it still did not help. I upgraded the air conditioner filter barely two months before the last upgradement, but that too did not work. Through research on what could absolutely be the cause, I learned more about HVAC than I had. I tried searching for its source, but my efforts were futile. I could not look forward to going home for almost a week, which eventually resulted in drastic measures. I hired a cleaning crew and called the local service provider I knew provided quality air conditioner service. I went through their cooling system care program and I decided that it was thorough enough; Apart from cooling system care, I also told the HVAC corporation to add HVAC duct cleaning to the list of services I needed. I had to restore high indoor air quality by all means. In a desperate attempt to find a solution, I switched off the a/c install just in case it was responsible for circulating lousy smell. I ensured that the a/c expert and the cleaning team tested the same morning because I was not too fond of the stink. It was less about HVAC maintenance and more about finding the root cause of my misery. When the tech and cleaning team finished, the smell had disappeared. The weird part was that none of them had come across anything that would have been the cause.