No heat/AC call, upon arrival customer stated they turned the AC on when it got a little hot outside, when customer tried turning heat back on they did not have any heat nothing was coming on, furnace was giving error code 24 fuse open, found popped fuse, checked ohms on contactor and contactor was reading 0.4 ohms, contactor was the reason for low voltage short, replaced contactor, tested system operation, checked capacitor, checked amp draw of inducer motor, and blower motor, temperature rise on furnace looks good, all units and electrical components working properly at this time. Recommended wet switch for emergency drain pan to prevent any water damage. Recommended homecare as well as better indoor air quality.