My house is heated & cooled by a packaged system situated right outside & attached to the air ducts that lead the conditioned air to vents in the ceiling. The plan is downright ancient. The two of us purchased this place a few years ago & immediately noticed the unlucky age, size & appearance of the unit. The two of us very much doubted this plan had the capacity to make it through a single winter. We’ve been pleasantly surprised by its reliable performance. In our locality, the Winter weather isn’t usually all that drastic, and now & then the temperature drops down into the upper thirties. At that point, my packaged device struggles a bit. It occasionally ices over. We’ve invested in a little electric space furnace to help out. In cooling mode, the plan has done a good job of handling the extreme heat & high humidity. Although it’s so noisy that it often startles myself and others when it kicks in, it provides a tremendous amount of cool air. We’ve never called for professional maintenance before. The two of us believe there is nothing but dust, debris & grime holding the components together. This past Springtime, we noticed that although the plan was still making its standard operational noises, there was virtually no air coming from the vents. I was upset about calling for some repairs. I prepared for the worst, figuring the Heating, Ventilation and A/C supplier would insist we invest in an entirely modern system. When the worker took the device apart, there was a significant build up of leaves, sticks & dirt within the cottageet. He found a small refrigerant leak. He said that replacing some of the parts was impossible because of the age of the system. He recommended adding refrigerant, charging it up & just seeing how long it would last. Since then, the plan has been providing plenty of cool air. I’m hoping it’s going to last us another few years.