Phase rotation reversed

**HVACAMAR** · 03-13-2013, 12:25 PM

Phase rotation(sequense) of panel feeding HVAC unit got reversed. When unit started smoke came out of vents. Unit stared in heating mode. Any idea what happened and what to fix.

**toocoolforschool** · 03-13-2013, 12:58 PM

What type of unit is this three phase, single phase, Resi or commercial, what burned up, have you had anyone look at it yet?

**HVACAMAR** · 03-13-2013, 01:06 PM

three phase commecial unit. Unit seems to be working fine now after phase rotation was corrected. I saw smoke from vents. Something burned temporarily. What could it be. Where to look.

**nolaHVAC** · 03-13-2013, 01:11 PM

Is it a new unit? Also, what brand/type?

**toocoolforschool** · 03-13-2013, 01:17 PM

Originally Posted by HVACAMAR

three phase commecial unit. Unit seems to be working fine now after phase rotation was corrected. I saw smoke from vents. Something burned temporarily. What could it be. Where to look.

I would start with the motor if I was qualified to do so.
In other words it could bre hazordous.

**ADillon** · 03-13-2013, 01:34 PM

blower motor if anything

**bustedknuckles** · 03-13-2013, 08:18 PM

If not a fried motor I have had knuckle heads leave or put paper in the returns.

**billg** · 03-13-2013, 08:35 PM

Don't give us a clue what it is, just let us guess. If its electric heat the coils will smoke if you don't move air across them but they can still work if you catch it quickly enough.