Have a new Trane Voyager 14 Ton unit which was recently started by another tech at my shop. Got a callback due to typical Trane burner whistling (high pressure symptom). Check gas pressure and reading 0.40" wc so I immediately think it's way off. I verified the rating plate and to my surprise it says manifold pressure = 0.30
I've never seen a positive manifold pressure on one of these. I throttled it down to 0.3 and still had minor intermittent whistling. I'm under-firing it slightly at 0.25 at the moment and whistling seems controlled.
Have any of you seen a new Voyager rated for positive gas pressure?