Speaking as a non-PRO, most references to 'auto-system' that I've seen refer to the thermostat to have the ability to switch between heating and cooling, where the climate has high daily temperature swings. Are we talking about system heat/blower auto?

Is the thermostat one that will control a heat pump? If it is a proper stat, with dual fuel kit installed, it should work. Did you try setting the stat to (plain) heat?

V

Yes, our auto-system does allow the system to switch from heating to cooling b/c of temp swings. Our system did that switching well during the early fall.

Not sure what you mean by 'system heat/blower auto'. The fan is on auto, and under the System heading we have Emer. heat, heat, off, cool, auto. We have put the system on "heat" instead of "auto" at this point, to see if that is the correct way to solve our problem. Thank you.

"We have put the system on "heat" instead of "auto" at this point." Yes, that is what I referred to.

On my stat, there are 2 blocks with options: One, (system) for heat, cool, auto; and (fan) for auto, on, program.

I guess you'll need some cold(er) weather.

V

i thought new HE furnaces had sealed combustion chambers? how is it that you can see the glow of the igniter? that seems odd. maybe i dont know how new high efficiency units work.

A typical HE furnace has two sections; one, the blower section; the other, the heating section. They are separated and sealed from each other, as well as the 'atmosphere'.

Access is gained by removing front panels on each section. In a (true) sealed combustion unit, the burners receive their combustion air from outside, if piped. The igniter is positioned so that the flow of gas can be lit.

Has your problem been solved?

V

Since we have changed the setting to "Heat", and it's not on "Auto" any more, things have been good. So maybe it's more of a system hiccup than anything else. We'll resume the "Auto" setting in the late spring/early summer, so it can do its flippy thing as it needs. Thank you for all comments. Talking about it has helped a great deal.

This is really strange. If you see a glow in the sight glass that means that the ignitor is glowing, waiting for pilot gas from the gas valve, and it is not coming. I had the same problem, and mine WAS a gas pressure problem. Mine would light off after about the third try, so I suspected low presure. Upping the pressure a bit solved the problem. I am not a pro, but I suspect that something is wired wrong between your furnace and your thermostat. Did you try killing the power and rebooting the system with it on auto?