MLD wrote:

Have a new High Efficiency Trane Gas Furnace. Every time it fires up the
picture on a TV set (rabbit ears antenna) on the floor right above it goes
haywire. The picture becomes almost unwatchable because of all the noise
streaks and snow in it.

I have a brand new high efficiency AUY American Standard furnace, which is
exactly the same as the
Trane XV90, except for the exterior label. It has a variable speed fan motor
and a variable speed exhaust (aka draft inducer) motor. I've noticed the same
thing that you have, the draft inducer motor makes a lot of e-noise. The noise
starts as soon as the inducer motors starts (e.g. before the burner lights and
before the blower motor starts) and ends as soon as the inducer motor stops
(e.g. when the burner shuts down but the blower is still operating), so I've
determined the inducer motor is the source of the noise.

In my case, we have cable TV and I've only noticed the noise on AM radio. The
noise is quite on all stations except for a 50,000 W station 2 miles away, and
even on that station the furnace noise is audible in the background.

I haven't complained about this noise yet (trying to get a sizing error fixed)
but am interested in any resolution to this problem---you're not alone!