Baltimore sits at the northern edge of the humid subtropical climate zone. Summer dew points regularly exceed 70 degrees. Your evaporator coil condenses gallons of water per day. That water drains into a pan and exits through a PVC line that runs to the exterior or a floor drain. When that line clogs with algae or sediment, water backs up into the pan. The float switch kills the system to prevent overflow. You feel warm air because the system shut down, not because anything broke. Coastal cities like Baltimore see this failure more often than inland cities. The moisture load is constant.
Baltimore's housing stock also amplifies cooling problems. Rowhomes in Hampden and Remington have shared walls that trap heat. The HVAC system fights not just the outdoor temperature but also the radiant heat from the neighbor's attic. Federal Hill homes have minimal insulation because they were built before modern energy codes. The cooling load exceeds the system capacity on the hottest days. Choosing a local technician who understands these variables means you get a solution that works for your building, not a generic fix that fails next summer.
