Had a new Tempstar HVAC unit installed during construction. Have used AC for past 4 months without an issue. Switched to heat this morning for first time and within 3 minutes there was a smell of smoke throughout the house (which I thought was normal for first use) and the smoke detectors went off. Reluctant to try using the unit again until I confirm that this is normal - contractor out of town and can't get in touch with unit install company.

Thanks!

Call the installer back and have him check it. Unit is under warranty.