Which Trane

[chrisva]

Hi,

Okay, we've decided to have our six-year old Janitrol gas furnace replaced with a new Trane high-efficiency heatpump system. Of all of the XLIs, which is the most cost effective in terms of upfront capital cost versus energy savings? And, since we have natural gas now, should we even consider using that as backup/auxiliary heat, given the volatility of the natural gas supply and cost, or just go with the electric backup? Or will we never recoup the cost of the gas back-up, given that it will be used very little? BTW, we're in Central Virginia, have had heatpumps before and don't have any issues with the "cool" heat, so the gas backup would only be installed if that, in conjunction with the heatpump, will yield a net energy savings greater than a straight heatpump.

Thanks all...

[BaldLoonie]

Unless you are taking gas service out of your house completely, I'd use gas as backup. From an economic payback standpoint, chances are the XL14i would be the best combo between first cost and energy savings. If money is no object, then the 16 or 19 would be the choice.

[dan sw fl]

Originally posted by BaldLoonie
From an economic payback standpoint, chances are the XL14i would be the best combo between first cost and energy savings.

I would definitely compare 1st cost of XL14i and XL16i to see how it fits your budget.

[heatpumpguru]

XL14i is nice but if your staying xl16i is nice for the long haul and humidity control.Fires 1/2 on most days,unless hot or cold.

[chrisva]

So it sounds like we should go with either the 14 XLi, with gas backup, or 16XLi without. And how does the gas backup work? Is it simply a gas burner in the air handler, or do we wnd up with a gas furnace with heatpump?

[wyounger]

You get a furnace instead of an air handler. So yes, it's a furnace with a heat pump instead of an AC.

I usually recommend a nice 80% efficient furnace for dual fuel applications. You don't need high efficiency because you won't use the gas burner much in the first place, so skip the 90+% units. The reason to get a nice one, though, is for the variable speed blower.

As for the decision as to whether or not to use electric or gas as your backup heat, a lot of that question will depend on how far away your breaker panel is, how hard it will be to pull a big wire over to the furnace/air handler location, and if your electrical service is big enough to handle electric backup. Usually the backup heat for an all-electric heat pump, on a single family home, is at least 10,000 watts- usually a 90 amp circuit. If it's going be a big pain and expense to switch to electric, then your question is pretty much answered for you.

[Edited by wyounger on 09-26-2005 at 02:37 PM]

[chrisva]

Thanks!