Help, someone please! I have a Carrier heat pump with a White Rodgers programmable thermostat that keeps tripping off the settings we use to program... next thing you know the a/c is off and the house begins to warm up to 85 degrees the White Rodgers thermostat defaults to because technically a/c is "off" when this occurs. Sometimes this happens in the middle of night and we wake up in a sweat. This occurs randomly and the only thing I can think of is the White Rodgers thermostat is on the fritz. We just had our biannual tech inspection and I told the tech about our little thermostat problem and he assured me the wires to the air handler were good... I thought I had a short-circuit issue from vibration, but when the thermostat works, the a/c system works!

So I've decided to replace the White Rodgers thermostat with a battery-backed up Hunter programmable thermostat I bought at Lowe's.

My problem is wiring. The White Rodger thermostat is currently wired to terminals R, C, E, Y, W2, E, O/B, and G. The new Hunter thermostat is designed for a multitude of systems and the manual lacks specificity. I need to know, for Carrier heat pump, do I hook the orange wire that went to O/B (on White Rodgers) to the Hunter's O connection or use the jumper wire to cross O and B on the Hunter terminals. Or, do I leave the jumper wire on the Hunter terminals connecting RC/R and RH (the way the thermostat terminal connection was wired in the box) and do I only connect the orange wire to the Hunter O terminal (and not B).

I did as much research on the internet as I could, and I suspect the Carrier heat pump uses the O terminal because it is a "cool mode powered reverse valve" system - yes? Is this the right connection to use then? Rc/R, C, Y1, W2, E, O, and G?

Wiring White Rodgers to Hunter for Carrier heat pump - my best guess:
R to Rc/R; C to C; Y to Y1, W2 to W2, E to E, O/B to O; and G to G is this correct??

Appreciate the tech support!!

Except from the standpoint of Hunter reliability, you appear to be set.

O/B sense should be changeable in software if it isn't right. You'll get heat when your supposed to get cool air if it's wrong.

Everything else looks OK.

Thanks, KISS. Do I leave the jumper wire the way Hunter has it installed? Or do I take it out?

Rc gets connected to Rh and this connection becomes R.

If you click on "Heating and Air Conditioning" link, top left, there is a "Sticky" that explains these terminals.

( quote) Except from the standpoint of Hunter reliability, you appear to be set.

KISS was sending a hint,, I`ll tell you straight up,you will be very lucky if the Hunter lasts 6 months,they all are junk,its not to late to take it back to Lowe's to trade it for a good honeywell,, Lowe's is used to it ,why they don`t quit selling them I`ll never understand,its probably because by the time people figure out they (hunter) are junk its to late to return for refund

Ladies and Gentlemen:
Take their advise! I took my Hunter Model 44860 back to Lowe's; got my refund and went straight to Ace Hardware and upgraded to the Honeywell RTH8500D!! Straight up, this was a wise decision! The Honeywell instructions for wiring and system setup are straight forward and took the guess work out of hooking up and I have a Carrier heat pump, which as I've learned, heat pumps in themselves confound the issue of simple thermostat swap out.
The only comment I'd have to say, is that for the Honeywell schedule setup, you have to touch the "schedule" button on the screen twice to enter the "edit" mode to start your programming. Other than that the setup was easy... just follow the steps in the manual!
I do want to thank KISS and all the others out there who've come across what should be so simple a handy-man job as a thermostat replacement.
One more note - if you're looking for a high-end Honeywell programmable, don't waste your time going to Sears... they don't sell thermostats in their store.. can you believe that? Lowe's and Home Depot usually don't have the high-end models either. The RTH8500D Honeywell at Ace ran me $120 and three AAA batteries, but if it gives us the years of trouble-free service that our old White-Rodgers failed to do... it will be money well spent.