3 years ago, I had a complete HVAC cut-in on my house. They installed a
Lennox 12ACB air conditioner, a Lennox G40UH gas furnace, and an
Aprilaire 2400 air cleaner. The systems all run great, but I've never
changed any filters. Where are they is the question? I see that the
Aprilaire one is easy to change. Is there also one on the A/C or
furnace unit?