Just replaced my digital therm, does the blue wire that was in C for the old therm go into "O", or "B" now? New therm is a Braeburn. Also do I have to reset something at the furnace?

rv repair place should be able to order one

What make and model of AC, as well as Make, model of thermostat ? Need that info for proper diagram.

You need to get a different thermostat.you can change an analog thermostat to digital, but you have to replace the motherboard with a digital compliant one. You can't just change the thermostat. Your best bet is to put back the old thermostat or upgrade to a different compatable thermostat

Hi smargyle,

Welcome to fixya!

I can provide you with diagrams for the old Carrier therm and for the new Filtrete therm. But, I would need to know what the model numbers are for each therm plus how many speeds AC you have.

Please reply back with that information and we will get your AC back in working order.

Thanks,

Handie Andie

I was replacing a DUO-Therm 3105058 Rev A. very old Thermostat in a Coachman RV with 3106995.032 from Amazon. After looking all the information on the directions it was clear I would have to play a hit or miss on some of the wiring. Instead of using the same coding, such as RC, RH, G, Yellow and such. they used the function and I had to guess at some.
Here is the wiring I found worked:
There are 6 wires. One set of two wires (white On the W & red on the RH) and the set of 4 (yellow On the Y, green on the G, red on the RC and blue on the H). So to keep it simple the red on the RH went to the +7.5. The White on the W went to the FUR. HS/HP not used. the Yellow from the Y went on the cool. The green on the G went to the fan. The red on RC went to GND. and the Blue on H went to Hi fan.
So red (RH) of the 2 wire goes to +7.5
White (W) of the 2 wire goes to FUR.
Yellow (Y) to cool
Green (G) to fan
Orange or red from the RC lug goes to GND
Blue (H) goes to Hi Fan

Y=yellow (a/c)
G=green (fan)
O=orange (reversing valve)
C=blue (common)
R=red (hot)
W=white, jumper to E (emergency heat)

Open following link to see clear drawing and instructions for wiring ST01C timer.
Page also has EZ programming steps:
http://waterheatertimer.org/ST01C-program.html#ST01C

Red wire is capped.
Blue wire goes to Load (wire to sconces)
Black wire connects to Line wire (wire from breaker)
Green wire goes to ground.
If you are uncertain about Load and Line wires, just connect them either way, turn power ON, push on-off button, it lights don't come on, then reverse wires.
I have tested this timer, and information here is correct.
Don't forget to install CR2 battery, otherwise display will not show.

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You will have to have schematics from the old wiring diagram. Then you will have to confirm its consistency with actual old wiring before you can be sure that the wires run to the proper places on the old heater and a/c system. This sounds like a gas furnace and is simpler than a heatpump. Once you know what distinguishes the wires with the same color, you should label them and then you may call them a different color if they were wired with wrong wire colors. You may be in luck if you go to the furnace control box an look at the terminals.. They are usually labeled with a R for Red and W for white and Bl for Blue and B or Black. If you have other colors on these then it sounds that it was wired with wire spare wire by someone who knew what they were doing but neglected to leave a path for someone else follow.
You may be able to use a continuity tester of circuit tester to id these wires that are in question...
ie, once indintified, you can match with the requirements of the new stat.

red and white are positive and neg 12v
green is low fan
grey is high fan
yellow is cooling
blue is neg 12v(marked B-)