There was a bit of confusion with the filters on my HVAC system. Alpine Climate Control, Inc. installed this system for me in a rental home. This system has the ability to be moved, and that is what I wanted. The engineering that went into this system was great and Mick worked diligently to get it installed in this older home. The sizing and placement were great. There are two separate units, one upstairs and one downstairs. The downstairs unit has two filters, and the upstairs unit has two. Since installation in 2018, there has only been one filter in the upstairs unit. I went in to purchase the filters for the upstairs unit and there was some confusion with the two gals that were there to assist me. I ended up with two downstairs filters. The upstairs unit used different size filters and those had to be back-ordered. These are not cheap filters. I paid $300 for filters that I didn't need. The technician that came out to service these units showed me how to clean the outdoor filter and that was good. He was kind and thorough in his work and pleasant. I feel that I shouldn't have had to purchase the filter for the upstairs unit because it never was put on when the install happened. I think it was missed in all of the packagings. Perhaps checking everything prior to leaving would have resolved that issue. I also that I shouldn't have to purchase the filter for something that was never done correctly in the beginning. The manual for this system tells me to replace the filters once a year but Alpine Climate Control, Inc. says that cleaning them would be just fine. This company is at the top of the line for the service of HVAC systems in my area. After the holidays I will go back and have a conversation about the filter situation and what is the best way to care for those filters.