I arrived for a blue club member summer tune up. I first removed and pressure washed all filters. I then inspected both indoor evaporator coils and found them to be clean. I checked the systems temperature drop and amp draws on both systems. I did find a water stain on the floor of the 2nd story walk way. I traced the water stain and dated the mark. It looks like the flue had been sealed with silicone once it had started leaking. This is a 90% furnace. To properly fix this issue would be to cut the fitting that is over the water stain and replace a section of pipe. I then inspected the outdoor system we installed and found both condensers to be fairly clean with minimal debris on the coils. I clean the condenser ps and checked all readings in high and low speed and found no issues.