Gas and Oil Home Heating Furnaces - thermostat will not hold program?

I have a White-Rodgers / 1F97-51 / 7 day Programable Electronic Digital Thermstat, approx. 4/5 years old. Recently when entering "run program" or "hold", the (actual) temp. reading goes down to (02 degrees F.), then gradualy raises to correct room temp. and system turns on!! Can anyone out there tell me what the problem is, if (I) or a repair person can fix this and how, and if if possibly, could this problem be under warrenty? Also, how could I change to a (manual) unit myself, thanks.

Go to home depot, buy a t'stat and follow the installation instructions. Make sure you get the right type of t'stat for your type of system.
If I understand your post, your saying that the t'stat temp goes down two degrees from the set point before the heat starts? If so, break out your t'stat programing instructions. That may be adjustable.

Thanks for your reply, let me try to make myself clearer, for example, say a themostat's "set point" is 68 degrees F, the (Actual) room temperature will read 68 degrees. If I change anything on the controls, the (actual room setting temp.) goes immediatly to the (02 degrees F, then 03, then 04, and so on, all the way back up to 68 degrees and furnace will turn on, it's not just 2 degrees off, ok, does this help?

Junk it, the electronics have gone bad. Warrenty on WR t'stats is one year, so no warrenty.

I WAS AFRAID YOU WERE GOING TO SAY THAT, UGH!!! IS A REGULAR THERMOSTAT LESS APT TO HAVE THIS PROBLEM THAN A DIGITAL? THANKS A LOT!

Mechanical t'stats are very dependable, but have no set back or temp monitoring. They are very easy to install and ususally cheaper.

One more question please, I have a Tempstar DC90 (high efficience) 4 year old furnace, can you give me your top mechanical choices, (ease of instalation/ dependability at best price) for a thermostat. Also is there a certain rule of thumb to know, as I am a novice at these things, thanks again. We have no Home Depo nearby.

Most mechanical t'stats use a mercury bulb type temperature sensing device, so must be installed as level as possible to sense correct temperature. Also they have a heat anticipator that must be set for heating cycle.
My personal choice is Honeywell's T-87f with heat/cool sub-base. There are alot cheaper one's on the market, but I've found the T-87f to be about the best.

Dear service tech, I went to Honeywell's website and couldn't pull up the T-871, does it have another name or numbers? Thanks again.

If you lood again. T87F..I used lower case T87f

Dave, listen to me. Your stat is 4-5 years old. Whitey makes some of the most reliable thermostats I have ever encountered. Does it have batteries? I assume you checked that. Then just replace it with the same model W/R stat. You wont find many thermostats that will cover the old foot print of that stat either. My company replaces about two hundred mercury bulb stats with W/R 1F80-24's a year and I have only had about three fail in four years. (I replaced them N/C.) You will be dissapointed if you expect to find a better stat. But we americans just love to shop dont we?

THANKS FOR YOUR REPLY,ARE YOU SAYING THAT IF THE BATTERY BACKUP DISPLAY IS "NOT" BLINKING IT COULD STILL NEED BATTERIES? THERE ARE BATTERIES IN THERE, COULD THAT BE THE PROBLEM? ALSO, I HAD THE FURNACE INSTALLERS PUT IN MY THERMOSTAT WHEN THEY INSTALLED THE FURNACE, WHAT DO YOU MEAN REPLACED AT (NO COST), PLEASE EXPLAIN FOR ME, THANKS.

Try changing the batteries first even if the low on battery warning light didn't come on. Cheap fix maybe. $1.50

I was thinking you may have had a battery powered stat. But I looked it up and yours is the 24VAC type. The batteries are strictly for back up. This of course would not cause your problem. By now you know you must replace this thing. I would recommend WR 1F80-24. For many reasons this is a great stat. It is also battery powered, not battery backup. If you know anything about electronics, 99 percent of failures is in the power supply section of anything electronic. This includes thermostats. My batteries in my stat are 4 years and still going. The same is true for my customers. When they need to be changed the stat displays "Battery". Battery power is smooth and reliable and therefor so is the stat. LUX is a division of Robertshaw corporation whom also makes stats. LUX is available at many hardware stores, and is a superior product to anything Honeywell makes. The company that installed your stat is not likely to replace it after 4-5 years. Good Luck.