Capt. Kaos Posted February 24, 2009 Share Posted February 24, 2009 Yesterday this seemed simple enough, tonight I'm ready to rip a huge hole in my damn wall. I got the bright idea in my bored to tears mind that this would be a good "take my mind off no job" project. We have (had) an old mercury tilt thermostat, I want to replace it with a programmable digital one. Anyone with knowledge of this process?!?! I have an 8 wire Trane Heating/Cooling System. What type of thermostat works with this system? So far I have tried 3 different ones and no luck finding one that works. I can give/get you any other info you may need. Thanks in advance. Link to comment Share on other sites More sharing options...
DButz65 Posted February 24, 2009 Share Posted February 24, 2009 Mostly any will work, but is it a heat pump system or furnace? Have good company come out and do it, just saves headaches in the long run. p.s there are all kinds of thermostats, someone that know what they are doing will know what kind you need for sure http://www.olympicaire.com/dLearn_More/dClimate_Control/Thermostats.php Link to comment Share on other sites More sharing options...
DButz65 Posted February 24, 2009 Share Posted February 24, 2009 Damn double post, forum hiccup Link to comment Share on other sites More sharing options...
DeanCollins Posted February 24, 2009 Share Posted February 24, 2009 Capt. K, I bought a realatively cheap programable thermostat from Homo depot, after my HVAC buddy told me to just let him bring over a $150 Honeywell. The one that I bought wouldn't work right and then I called him and told him I was a fool and he was right lol. the wiring is fairly complex for some reason. Try calling a Trane tech on the phone or better yet, there are some great HVAC message boards full of Techs that will help with a wiring diagram. the Trane is a bit different from most. I had Trane XL14 heat pump Link to comment Share on other sites More sharing options...
Capt. Kaos Posted February 24, 2009 Author Share Posted February 24, 2009 Mostly any will work, but is it a heat pump system or furnace? Have good company come out and do it, just saves headaches in the long run.p.s there are all kinds of thermostats, someone that know what they are doing will know what kind you need for sure http://www.olympicaire.com/dLearn_More/dClimate_Control/Thermostats.php Thats part of my problem. I think it's a heat pump w/ aux heat but I'm not 100% Link to comment Share on other sites More sharing options...
DButz65 Posted February 24, 2009 Share Posted February 24, 2009 Thats part of my problem. I think it's a heat pump w/ aux heat but I'm not 100% Aux heat just means it uses alot more electricity to run in aux mode. On the newer digital thermostats this means if you have it set to 2 degrees above the current indoor temperature, it kicks in the aux heat, if its only set to 1degree above its more efficient(electricly speaking) the old mercury thermostats threshold for aux heat was about 3-5 degress Link to comment Share on other sites More sharing options...
HOF44 Posted February 24, 2009 Share Posted February 24, 2009 I guess I was lucky, bought a Home Depot digital and wired it up and it worked fine. I have gas heat though. Link to comment Share on other sites More sharing options...
Capt. Kaos Posted February 24, 2009 Author Share Posted February 24, 2009 I guess I was lucky, bought a Home Depot digital and wired it up and it worked fine. I have gas heat though. Oh, good point..... it's electric Glad things went smooth for ya Bob! Link to comment Share on other sites More sharing options...
DButz65 Posted February 24, 2009 Share Posted February 24, 2009 CK the best thing to do is call a hvac company and tell them your situation, preferably a trane technician, and give them your system info, they'll have someone come out to check the system out and give you prices on what thermostats will work with your current system. I know you said you are jobless atm, but it shouldnt be all that much and should only take someone 30 mins to wire the new thermo up and test it, IF they know what they are doing. Link to comment Share on other sites More sharing options...
Capt. Kaos Posted February 24, 2009 Author Share Posted February 24, 2009 Capt. K,I bought a realatively cheap programable thermostat from Homo depot, after my HVAC buddy told me to just let him bring over a $150 Honeywell. The one that I bought wouldn't work right and then I called him and told him I was a fool and he was right lol. the wiring is fairly complex for some reason. Try calling a Trane tech on the phone or better yet, there are some great HVAC message boards full of Techs that will help with a wiring diagram. the Trane is a bit different from most. I had Trane XL14 heat pump Thanks! I was planning on hitting a few other websited tomorrow. I always give my ES brothers/sisters first chance to help me out. It always amazes me the amount of knowlwdge contained within this site. Link to comment Share on other sites More sharing options...
Cassow Posted February 24, 2009 Share Posted February 24, 2009 Thats part of my problem. I think it's a heat pump w/ aux heat but I'm not 100% When your heat comes on normally does it blow really warm air? If so, you have a furnace. If it blows air just slightly warmer than the air in your house, you have a heat pump. Take a good look at the old mercury unit...it should have heat pump/furnace written on it. They do sell units that work for both though. When you removed the cover plate and saw the 8 wires did you carefully mark which wires were which? Sometimes the lettering (O, Y..etc.) on the unit don't necessarily match up to the colors of the wiring. Hopefully you labeled each wire properly before un-wiring them. My guess is you have some cables crossed. Link to comment Share on other sites More sharing options...
Capt. Kaos Posted February 24, 2009 Author Share Posted February 24, 2009 When your heat comes on normally does it blow really warm air? If so, you have a furnace. If it blows air just slightly warmer than the air in your house, you have a heat pump. Take a good look at the old mercury unit...it should have heat pump/furnace written on it. They do sell units that work for both though.When you removed the cover plate and saw the 8 wires did you carefully mark which wires were which? Sometimes the lettering (O, Y..etc.) on the unit don't necessarily match up to the colors of the wiring. Hopefully you labeled each wire properly before un-wiring them. My guess is you have some cables crossed. Found the original paperwork, it is a heat pump and Yes, I labeled each wire as I unhooked it from the original thermostat even though all the wire colors matched up except for black which was marked X2. Not to say I dont have a wire or two crossed. At this point I have til tomorrow early morning to have this figured out or she wants me to make some phone calls. I'm starting to think I may be making some phone calls tomorrow. yet another blow to my already bruised male ego! :mad: Link to comment Share on other sites More sharing options...
Cassow Posted February 24, 2009 Share Posted February 24, 2009 Found the original paperwork, it is a heat pump and Yes, I labeled each wire as I unhooked it from the original thermostat even though all the wire colors matched up except for black which was marked X2. Not to say I dont have a wire or two crossed. At this point I have til tomorrow early morning to have this figured out or she wants me to make some phone calls. I'm starting to think I may be making some phone calls tomorrow. yet another blow to my already bruised male ego! :mad: Connect X2 to W2. If that doesn't do it, I would give someone a call. I can only imagine the crap your wife giving you for deciding to change the thermostat in the dead of winter and effing it up:D Good luck man! Link to comment Share on other sites More sharing options...
Capt. Kaos Posted February 24, 2009 Author Share Posted February 24, 2009 Connect X2 to W2.If that doesn't do it, I would give someone a call. I can only imagine the crap your wife giving you for deciding to change the thermostat in the dead of winter and effing it up:D Good luck man! Thanks man! I'll give that a try. Link to comment Share on other sites More sharing options...
Joe Sick Posted February 24, 2009 Share Posted February 24, 2009 My wife replaced ours with a $50 one from Lowe's in like an hour and a half... Link to comment Share on other sites More sharing options...
Cassow Posted February 24, 2009 Share Posted February 24, 2009 My wife replaced ours with a $50 one from Lowe's in like an hour and a half... CK...maybe you should give her a call. Link to comment Share on other sites More sharing options...
DButz65 Posted February 24, 2009 Share Posted February 24, 2009 I'm starting to think I may be making some phone calls tomorrow. yet another blow to my already bruised male ego! :mad: My wife replaced ours with a $50 one from Lowe's in like an hour and a half... Wow CK that just has to make your ego feel even better@! Link to comment Share on other sites More sharing options...
Rumrunner6900 Posted February 24, 2009 Share Posted February 24, 2009 I was looking to do the same thing, but for some reason if you have a heat pump with auxillary, you have to buy a certain thermostat and it sounds like it may be a bit more complicated. I was gonna do it myself as well, but after reading this, I may just have someone who know their **** do it. Don't let it bruise your ego either...better you get help before you **** something up even more and look like a total idiot! Link to comment Share on other sites More sharing options...
DButz65 Posted February 24, 2009 Share Posted February 24, 2009 Don't let it bruise your ego either...better you get help before you **** something up even more and look like a total idiot! Right because getting just one wire backwards could fry a capacitor or something, then it will cost a lot more to fix Link to comment Share on other sites More sharing options...
Capt. Kaos Posted February 24, 2009 Author Share Posted February 24, 2009 Wow CK that just has to make your ego feel even better@! heh, if someone hadnt already shared with me that my particular manufacturer was a little more difficult to work with then yes, that would have stung a little. Link to comment Share on other sites More sharing options...
Capt. Kaos Posted February 24, 2009 Author Share Posted February 24, 2009 I was looking to do the same thing, but for some reason if you have a heat pump with auxillary, you have to buy a certain thermostat and it sounds like it may be a bit more complicated.I was gonna do it myself as well, but after reading this, I may just have someone who know their **** do it. Don't let it bruise your ego either...better you get help before you **** something up even more and look like a total idiot! I'm running in to the problem of not being able to find that "certain" t-stat. Link to comment Share on other sites More sharing options...
Rumrunner6900 Posted February 24, 2009 Share Posted February 24, 2009 I'm running in to the problem of not being able to find that "certain" t-stat. It's a pain in the ass and everyone I have found is expensive as hell. I would like to have digital thermostats (yes I have 2 heat pumps :doh: )for the energy savings, but the start up costs can be a *****! Link to comment Share on other sites More sharing options...
DButz65 Posted February 24, 2009 Share Posted February 24, 2009 CK i've got this spare thermostat laying here that you could have if you want to give it a shot, it wouldnt work with the new system i had installed last spring, i could ship it 2nd day. I had it installed about 3 weeks before our old system died so it hardly got used http://www.pexsupply.com/product_dtl.asp?pID=4078&brand=&cID=396 See if you can find out if it will work with your system or not, if so its yours Link to comment Share on other sites More sharing options...
Capt. Kaos Posted February 24, 2009 Author Share Posted February 24, 2009 CK i've got this spare thermostat laying here that you could have if you want to give it a shot, it wouldnt work with the new system i had installed last spring, i could ship it 2nd day. I had it installed about 3 weeks before our old system died so it hardly got used http://www.pexsupply.com/product_dtl.asp?pID=4078&brand=&cID=396 See if you can find out if it will work with your system or not, if so its yours let me find out if I can use it and I'll let ya know. Good looking out! Link to comment Share on other sites More sharing options...
DeanCollins Posted February 24, 2009 Share Posted February 24, 2009 Capt. K I found this, hope it helps. Of course if we knew the brand of thermo and model of trane... " > Below is the result of your feedback form. It was submitted by > () on Friday, November 2, 2001 at 17:41:22 > --------------------------------------------------------------------------- > > Brand: Trane > type: heat-pump > fuel: electricity > location: basement > Problem: temperature > email address: m.d.mcaninch@juno.com > S1: I have a Trane heat pump with auxiliary electric heat controlled by > a Trane Weathertron thermostat. I am attempting to upgrade the > thermostat with a programmable Hunter model 44428. I am having trouble > verifying the correct wiring hookup for Hunter thermostat to the Trane > unit. So far, neither the local Trane rep. or the Hunter web site > contact has been much help. The current hookup for the Weathertron > controller is: > > > Terminal "F" (color-none) Purpose-Not used, > Terminal "B" (color-Blue) purpose-24 volt common > Terminal "X2" (color-Black) Purpose-Emergency heat? > Terminal "W" (color-White) purpose-First stage Aux. Heat, Terminal "T" > (color-Tan 0 purpose- Outdoor Thermistor, Terminal "G" (color-Green) purpose- > Fan, Terminal "O" (color-Orange) purpose-Reversing valve, Terminal "Y" > (color-yellow) purpose-First stage compressor, Terminal "R" (color-Red) > purpose-24 volt hot > > > The following are the referenced terminal connections in the Hunter 44428 > manual. > > > Terminal "R" Function-24 VOLT HOT > Terminal "Y" Function-FIRST STAGE COMPRESSOR > Terminal "W" function-FIRST STAGE AUX. HEAT > Terminal "W2" function-SECOND STAGE OF AUX. HEAT > Terminal "G" function-FAN > Terminal "E" funtion-EMERGENCY HEAT RELAY (ALWAYS ON IN THE > EMERGENCY MODE, OFF IN NORMAL MODE) > Terminal "A" funtion-NORMAL COMPRESSOR OPERATION > Terminal "0" funtion-REVERSING VALVE OPERATION > Terminal "B" function-24 VOLT COMMON. > > > ------------------------------------------------ > Based upon this I plan to make the following connections > > Trane "F" to no connection on the Hunter > Trane "B" to Hunter "B" Warning: SEE Note BELOW!!! > Trane "X2" to Hunter "E" SEE note below. > Trane "W" to Hunter "W" > Trane "T" to no connection on the Hunter > Trane "G" to Hunter "G" > Trane "O" to Hunter "O" > Trane "Y" to Hunter "Y" > Trane "R" to Hunter "R" > Trane ---no connection to the Hunter terminal "A" > > Can you verify that this is correct? I am unsure about hooking the > Hunter "E" terminal to the Weathertron "X2" terminal. Also, I am > assuming that the tan wire from the "T" terminal on the Weathertron will > not be used by the Hunter unit and that there will be no connection made > to the "A" terminal on the Hunter controller. > Thanks for the help in advance. > Mike (Weathertron is a Brand name of General Electric) GE/Trane thermostats use an outdoor anticipator similar to the one described here. The new electronic Hunter Stat will not need an out door stat ("T" lead) but some units do have them. The only purpose of the common lead on most stats is to operate the lamps unless it needs the 24 volt transformer to power the electronics. See Note below. The Hunter 44428 has the advantage of not using the electric heat unless necessary and when it does it will bring the room to the set point and shut the system off instead of running the heat pump forever. It has 2 W terminals that allows the electric heat to be broken into 2 stages. There is a reversing valve switch. It should be set to "RO" in most cases, "RB" if Rheem/Ruud. See Note below. The proceeding is an excellent question I wish every question I receive is like this. As I say in my other wiring page. It is more important to know what the colors and terminals do than to just match the colors with the letter of the terminal. In this case this person did just that (identify the function). Many manufacturers use the same terminal designation except for a few that change like "E" is emergency heat relay but it is not used on most units. "B" is energize to heat (Rheem/Ruud) the opposite of "O" but here it is "Common" what would be "C" or "X" on Carrier or Bryant. I checked a 3.5 ton Trane unit (General Electric is the same) and I found that "X2" is one set of auxiliary heat and "W" is the other. When the thermostat calls for auxiliary heat it energizes "W" when the outdoor unit calls for defrost it activates the "X2" line. If the unit has an outdoor thermostat (smaller units don't have one) it will connect "W" and "X2" together. I recommend for proper operation of the Hunter thermostat to disconnect the outdoor thermostat (pull one wire loose and tape it) and let the Hunter do it's job. When the thermostat is placed in the Emergency heat mode it also connects the two together. The "W" terminal is connected to the "AUX. HEAT" lamp, the "X2" is not. Smaller units under 3 tons may not have this extra heat circuit. I recommend using "W" as the 1st stage of heat (W1) and "X2" as the second stage (W2). If you are unsure leave it disconnected and if there are no problems leave it off while you decipher the wiring. It is better to have something not work than to fry the transformer or thermostat. Most GE/Trane units have a wiring diagram the inside cover of the outdoor unit control panel. Notes: the older Hunter 44428 does not have a common terminal ("C") the newer ones do! On GE/American Standard/Trane and York "B" is common, please do not confuse with Rheem/Ruud that use "B" to energize the reversing valve with the system switch set to heat. If you connect "Common" to the reversing valve "B" (or "O") you will blow out the transformer and possibly smoke the thermostat. "X" can be common on some systems, or the indicator lamp. On Trane/American Standard/GE "X2" is the second stage of electric heat connect it to "W2".If you have a Lennox system that uses terminals like: F, V, R , P, L and H ect. triple check the function of each wire before you connect a new thermostat!!! I have amended my wiring page and I will add it here too. I want to urge any one changing a thermostat, especially one this expensive in the strongest terms to check the function of each wire BEFORE you blow up your $80+ thermostat and the control transformer. Obtain a set of clip leads (available from Radio Shack) and a 1 amp fuse and test each function by connecting from "R" to each of the wires that needs to be connected to make the system work. If the fuse blows instantly then you most likely found the common wire or a defective component. An assistant is useful for verifying each function on the outdoor unit, the reversing valve and contactor. The electric heat functions should turn on the indoor blower.I also insist that you never replace a thermostat or any other components as a diagnostic or on a system that is not working correctly. Isolate the problem first. This part Written by Scott Meenen More to come... November 2006: Trane electric heat modification that will save you lots of $$$... If you have a larger Trane heat pump with 2 sets of circuit breakers for the electric heat then consider making this minor modification that could save you lots of money. On the indoor unit there are 2 electric heat channels (inputs) W1 and W2. W1 is on the first circuit breaker with the fan and controls and W2 is on the second one and stands alone. Move the black wires (X2) to W1 and the white wires (W1) to W2 and power down that circuit breaker, remove any jumpers that may connect both inputs. This simple modification will give you emergency heat and defrost heat but allow the heat pump alone to heat the house without the benefit (or cost) of auxiliary heat. If the weather gets too cold for the system to keep up then you can close the second circuit breaker. This mod works on other brands of equipment with a similar configuration. Link to comment Share on other sites More sharing options...
Recommended Posts
Archived
This topic is now archived and is closed to further replies.