I just learned I had a bad install on a Carrier 2-stage found by a factory authorized service tech. The installer wired it wrong so it could
never fire up on the high setting ever. Would this have caused combustion fumes to enter the house? Service tech said fumes could
enter the house this way, but it doesn't sound quite right to me. He said the furnace needed to fire up in the high setting to create a good seal.
Could the heat exchanger be faulty? I smelled odors coming from the vents and had trouble breathing. The installer blew me off.
Yes, I did my homework before having this unit installed and still got a bad install. I plan to call the installer's boss to complain.
Shouldn't cause fumes to come into house.
The simple answer is no - low fire vents the same way as high fire.
As for "smelling odors" - every new furnace we have installed (as well as new heat exchangers) upon its first firing burns off the oil which is on the HX. This makes smoke and often activates smoke alarms. Every new one.
From your description it doesn't sound like a bad installation. The installer just didn't set a DIP switch properly.
Sounds like the installer made a simple mistake, and there was never threat of injury or damage.
"factory authorized service tech" doesn't exactly mean anything. Just means that he went to a class.
Only reason I mention this, is he full of crap.
Every furnace has a bad smell when you start them up for the first time.
That's the stupidest thing I've heard in awhile lol. An oversized furnace may spend the majority of its life on low fire. Our trane xv95 calls for a jumper wire when used with a single stage stat, they Could have done something as minor as forgetting it.
they could have installed a unit that was toooooooooooo big for the house(got a good deal on it and made a profit on you) and running in high fire would short cycle.
or, as stated, they simply and honestly forgot to do something.