May 27, 2024 | Leave a comment | Home Indicators on How to troubleshoot common HVAC problems You Should Know blog here In the event you hear this seem, it is likely coming from your outside unit. The websites steel-on-metallic sound can often be because of the supporter motor bearings going out on your outside unit.Heat air coming from your vents is among the signs your AC needs repair. It could indicate an issue with the compressor or that your system is lower on refrigerant.