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Discussion Starter · #1 · (Edited)
I decided to upgrade my old thermostat with the new wifi enabled Radio Thermostat but I ended up with three wires that I did not use.

OLD

https://customer.honeywell.com/en-U...C Catalog&pid=T8575B2007/U#LiteratureDownload


NEW

http://www.homewerksww.com/radiothermostat/CT-30-Installation-16apr10.pdf


This is how I connected the wires:


no /color /function /letter on new unit
----------------------------------------------------
(1) RED -> Power -> Rc/Rh
(2) BLACK -> Common -> C
(3) BLUE -> Heat -> B
(4) GREEN -> Cool -> O
(5) - - e m p t y - -
(6) ORANGE -> Fan Common -> [did not use]
(7) BROWN -> Fan low -> G
(8) YELLOW -> Fan Medium -> [did not use]
(9) WHITE -> Fan high -> [did not use]



I assume that the 'Fan Common' wire is no longer needed but I'd like to know how to connect the other two 'speed control' wires to the new unit? Any help would be much appreciated.
 

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Can't help on the speed control but heat on the Radiothermostat (and most others) is not the Blue, it is W for single stage (or first stage of 2 stage units) and W2 for 2nd stage. And cool likewise is Y and Y2.
 

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Here is a chart of standard thermostat wire colors. The pros will weigh in here before too long but it looks like you have house wires that are non-standard colors. It might also help folks if you specified what kind of heat (gas, elec, heat pump, boiler, forced air) and provide mfg and model.

http://www.dr-fix-it.com/ttt/10005.html
Yes that list is very accurate on what the different terminals do, and the type of heating system would make a difference. Unless you have a heat pump you shouldn't be using O or B. Plus some of the functions you list don't make much sense. "Fan Common" won't connect to the stat and all the fan speeds you have listed aren't controlled by the thermostat.

The easiest thing to do at this point is go to your furnace & find where the low voltage wires hook in. Hopefully they'll hook to a board with the terminal designations on it. Those letters on the board should match the letters in your stat. Just write down every terminal in the furnace that has a wire to it & what color the wire is. Then go to your stat & make it match.
 

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I took O and B out and used Y1 and W1 instead. Thanks everyone for helping me out.
I guess that worked? After seeing the pictures you posted I wouldn't have the slightest clue what those terminals all do. That is one funky stat. If I came across that in the field I'd have to track it back to the furnace to see where all those wires went. If you managed to make that work you did pretty well.:thumbsup:
 

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I guess that worked? After seeing the pictures you posted I wouldn't have the slightest clue what those terminals all do. That is one funky stat. If I came across that in the field I'd have to track it back to the furnace to see where all those wires went. If you managed to make that work you did pretty well.:thumbsup:
I came across that brand last summer...what a piece of junk....Yes it had the internet features for a smart home, but if you bumped the tstat it blanked out. The HO put it in and was bringing the electric heat on along with the heatpump.....for no reason...:whistling2:

As posted above....you have to have tiny fingers to check the wires
 

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Discussion Starter · #11 ·
I guess that worked? After seeing the pictures you posted I wouldn't have the slightest clue what those terminals all do. That is one funky stat. If I came across that in the field I'd have to track it back to the furnace to see where all those wires went. If you managed to make that work you did pretty well.:thumbsup:
It worked well after switching the wires. And the WiFi feature is great :)
 

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Now that we're at this subject, what WiFi thermostats would you recommend? Let's say under $200.
Don't have much experience with the WiFi stats so I can't say persobnally know these are good, but I've heard good things about Nest Thermostats. The first generation model looks to sell for right at $200, 2nd Gen is $250.

http://www.lowes.com/cd_nest+thermostat_1335274929_
 

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You get what you pay for. If you wanted a cheap WIFI stat You definately got it.:thumbsup:
Yo Tech lighten up it is what it is the guy bought a thermostat he's just looking for a little help not to get his ass chewed out for a purchase.
Hampton Bay is known for ceiling fans I have a bunch of their $20 dollar stats out there for emergency and not one has broken or gave me any trouble. I know I know if it ain't Honeywell forgetaboutit. Believe me I've had many problems with Honeywell quite a few times. Your paying for the name. Let me have it all you nay sayers.
 

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Nest isn't compatible with Variable speed fans

The Nest isn't usable in this case. It doesn't work with variable speed fans.

I have this specific model of thermostat as well. I can't use the Nest (or practically any other standard thermostat) because the system I'm connecting to has a variable speed fan.

Hint to anyone considering a nest, check you existing system first and make sure you see the "normal" labels (those one/two letters) and that the wires are NOT stranded. If you see either, do yourself a favour and contact Nest first (you can email them a picture at [email protected])
 

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Boy thats all I need, Bill Gates controlling the heat in my house. "reset thermostat to 70 degrees" "Are you sure you want to reset your thermostat to 70 degrees?" "No I just typed that in for the Hell of it, I really want the house at 28 degrees to store frozen meat" "Command accepted, will reset to 28 degrees" NO, NO I dont want that" Blue screen of death, blue lips and blue skin. :thumbsup::thumbsup::thumbsup:
 
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