I just had a new Furnace installed (Goodman GCES960804CN) along with an evap coil (CE48D44210L004) and AC condenser (GSX140481) on Jan. 9th 2020 by professionals. Everything is new equipment and the air filter has been changed.
Now when i run the furnace it's making a vibration noise after it finishes its cycle, along with a burning oil smell. This happens randomly so its hard to make it happen when the HVAC person is here so that I can show him the vibrating noise and oil burning smell. Some days i can run the furnace for 6 hours without the noise and smell - other times it happens after it finishes its cycle.
Originally I figured it was overheating and the unit was shutting itself off to protect itself. But then it started happening early in the morning when the furnace was not in use through out the night. So it couldn't be from over-heating. Some small facts - the House is 1700sf two-story home. There are 9 vents. The old unit was a 3.5 ton unit and the new furnace is a 4 ton unit.
Can a few of you experts help me solve this issue?