I had a brand new Rheem Furnace/AC unit installed a few months ago and have been using the AC with no issues. Last night we turned on the heater for the first time and a really bad smell came out of the vents. It smelled like something was burning. We turned the heater off and opened the windows and the smell went out of the house.

Any ideas what may have caused this? A few people have told us that this is normal for new heaters. Is this true, and the installer just failed to mention this?

Please let me know what you think, Thanks.

Usually the first firing of a new furnace produces a burning smell, from the heat exchanger oils being burned off... as long as the installation techs set the gas pressures and proper air flow through the unit to factory specs... you should be OK, if you have ANY doubt, and / or the smell does not go away, re-contact the installing company to come back and recheck the unit!