Furnace Staging

[kb3ca]

My new Trane XV95 two stage furnace came set for staging after ten minutes.
Consequently, it runs in stage one almost all the time except for recovering from a set back. There are options of 30 seconds, 5 minutes, 10 minutes, and 15 minutes. How does one know what this setting should be? At first I thought that running in stage one most of the time would be the most economical but now I'm not so sure. Any suggestions from the Pro's?
Thanks

[beenthere]

So you got a 2 stage furnace, and crippled it by using a single stage thermostat(or your contractor did).

The thermostat should control staging. Have them install a 2 stage thermostat. Was a load calc done. Or did they just guess at size. An over sized 2 stage, is a waste of money. You don't get the comfort you paid for.

[kb3ca]

Thanks Been for the reply. The thermostat is the Honeywell Vision Pro IAQ but I'm not sure how it controls staging. The furnace has dip switches to set the staging time. For example, if stage one doesn't satisfy the demand then it goes to stage two after 10 minutes and this setting is adjustable. I assume that the thermostat would kick it to stage two if the droop of 2* occurred?? I'm sure the furnace is oversized somewhat but is it uneconomical to have it run in stage one most of the time?
It's a 100K BTU unit at 95% efficiency and puts out approx 65K BTU in stage one.

[beenthere]

The IAQ will bring on second stage when it determines that first stage is at 90% capacity of the homes heat loss. or coming out of recovery.

How big was your old furnace? And was it also a 90% plus furnace. You may be more over sized then you think.

There is a slight efficiency loss in first stage. With a proper sized furnace. You will never know it though. With an over sized one. I don't know if you will notice it on your gas bill or not.

[snupytcb]

your contractor should have gone over this stuff with you so you can better understand how it works.

[kb3ca]

The old furnace was a Trane XE90 100K BTU 90+ efficiency single stage unit.
I was just wondering if there are any economical negatives to running in first stage for 10 minutes versus changing the staging setting to 5 minutes or something else. The factory setting is 10. My initial impression was that if first stage is satisfying the demand then I am saving money over the old unit which ran at full capacity all the time. So, is it better to kick it to second stage earlier to heat up faster or let it satisfy the demand in first stage as long as it can?? This is what I was trying to get at in the original post.
Been-The thermostat isn't going to upstage the furnace as long as it meets the demand in first stage, right?
BTW, this is a dual fuel setup with HP and natural gas but I am running the gas furnace now because it's so cold outside.

[beenthere]

No harm in it running in first stage for long long long time periods.

Going to second stage after some arbitrary time period is not any better then running for 50 minutes in first stage. Going to second stage by time is a waste.

What thermostat do you have. Only a few can control both stages of your furnace in a dual fuel application.

[kb3ca]

Thermostat is Honeywell VisionPro IAQ set up for dual fuel.

[beenthere]

Ok. It can control both stages of your furnace. And it should be set up to.