Trane Baystat 239 to Honeywell RTH7400D

______________________________________________________________________ Wanting to go digital to save on electricity, but more importantly to control temp so it’s not to hot or to cold. This is turning into a nightmare. The first units I purchased do not work with a heat pump system or what ever I have. Fine I got a unit that is supposed to have heat pump support. However no matter what I do I get either fan, or fan and heat. In Florida, this time of year, heat blowing in my house is not funny. Hotter now inside than outside. After hours of trial and error my old one is back on the wall and my 85+ degree house is on it’s way back to the high 70′s. My Trane has in no particular order B Blue W White R Red T Brown Y Yellow G Green O Orange X2 Jumped white from W Now I get that the T is not used, but when I match up the rest to the wiring for a heat pump system. All I get is heat and no A/C. Seems Honeywell will not be open till Monday or so for support? Curious if anyone here has any ideas, or can suggest a digital unit that will install less headache and heat :) Oh and I have gone through a few fuses in the process, these wonderful 3 2/10 fuses. I am crutching it on 3 amp ones for now till I can locate more 3 2/10. For now using my old unit, and all I can think of if it ain’t broke don’t fix it. This is stupid, and I feel like getting in touch with some consumer agency. All this 99.9% crap advertise is total crap, and b.s. No way I am in the 0.01% as I have seen a ton of the Trane thermostats. Help please. Thanks. Replies: niko851 “Re(1):Trane Baystat 239 to Honeywell RTH7400D” , posted Sat 28 May 09:32 ______________________________________________________________________ First, you need to STOP this ‘trial & error” method for reasons you mentioned – you’re blowing fuses on the board and you are also risking frying the board and/or components. Now, you need to go to the units, both in and out, and record what colour wires are on what terminals. This is why you are having such an issue as you are mis-wiring the unit. There are jumpers that may need to be in place, the new stat has different terminals than the old, and without knowing what the old terminals/wires go to, it’s not going to be easy for us to help you without this info. The colours do not necessarily correspond with the letters; while I understand your situation of ‘it’s not funny’ as I, too, would be irritated as all hell if it was happening to me. The first step in the install manual is to LABEL the wires coming off of the stat and record what terminals they were attached to. Since you have the old stat back on, now’s the time to record that, go back to the inside & outside units, and see where the wires are on the terminal blocks. Bring that info here and we’ll be able to help. Niko Check your circuit breaker or fuses before calling for service – it could save you $$!! flheat “Re(2):Trane Baystat 239 to Honeywell RTH7400D” , posted Sat 28 May 10:25 ______________________________________________________________________ I have stopped the trial and error since I have exhausted all possibilities. As for labeling the wires, they are as they appear above. Just ignore the colors, but those are the exact letters and etc on the old Trane. Listed in my original post. Wires are labeled, and it just so happens the colors are similar to the letter. Neither thermostat has jumpers. I have already been to the actual unit an seen the wires on terminal block. No labels but it all looks good there? Most of my trial and error was on the O and B terminals, which are now O/B and C. Since it seems those ahve something to do with reversing a valve. Figured I might have had something reversed since I was getting heat with the A/C. Never any A/C? I have the wires labeled, but the differences in lettering on the units is driving me crazy. Like I had a W with a jumpe wire to X2. Now this unit has and AUX and L, where W now goes to L, and not sure if I should jumper it to Aux as well. Not to mention the whole O B thing? I mean I do not have that many wires, and I hooked it up exactly by letter, as I should, and nothing but heat. Starting to think more is required, and I can’t just replace the thermostat easily. At this point till I have a plan or information on what was wrong. I am not going to trial and error anything and leave my old one on and working in this heat. But I really would like a digital one and have been wasting allot of time. Thank for your help. niko851 “Re(3):Trane Baystat 239 to Honeywell RTH7400D” , posted Sat 28 May 13:23 ______________________________________________________________________ I also just sent an email to the email address you have listed; if that’s not one that you can get to (now), let me know what it is… Mine is: Niko Check your circuit breaker or fuses before calling for service – it could save you $$!! niko851 “Re(3):Trane Baystat 239 to Honeywell RTH7400D” , posted Sat 28 May 13:18 ______________________________________________________________________ You want to get a beer and have one w/me?? Just trying to make light of the nonsense situation…. First, what model is this equipment (both in & out)… This Stat, by itself, is a mini-computer for lack of better words. You have a (potential) slew of programming to do to set the thing up for the equipment you have. This is going to take some time to do – you’ll have to be patient, and I will too and do my best in helping you figure this out… In addition to wiring correctly, you have to setup the Stat for a HP application. By default, it is conventional, and there is a specific ‘area’ of the programming for “Installer Setup”. In this area, code # 0190 will specify what you want the O/B terminal to do – either changeover to heat, or changeover to cooling. If you leave this value at “0″, then the wire on “O” needs to go on the O/B terminal. Of course, this is again dependent upon whether you have a heating changeover or a cooling changeover. This ‘sounds’ like where the problem may be manifesting as you get heat all day long, but you’re not getting the cooling changeover. Also, this “T” (Brown) designation is another item in question; without a schematic on yoru equipment, I’m admitting I’m at a loss for that at the moment. Also, you need to let us know if this is a two-stage, one-stage (heat), etc. etc. as setup code 0170′s value will further determine how the stat is going to tell the equipment what to do. I’m going to speculate that you need to define this value as “7″, which is a Heat Pump w/aux heat. If this holds true for your equipment, change those values mentioned above and then the wiring. Moving on for now, here’s your existing: B Blue W White R Red T Brown Y Yellow G Green O Orange X2 Jumped white from W Referring to the HOneywell diagram, here’s what I’m coming up with: R = RED (24V) – also, leave the R to RC jumper; if not there, put it there :) G = GREEN (Indoor Fan) Y = YELLOW (Compressor Contactor) C = BLUE (Common) O = ORANGE (Cooling Changeover) AUX = WHITE (Heating, but possibly needs to be jumped to Y, but until we have the schematic on it, not really sure since the heating circuit was previouly jumped to X2, and the X2 designation on the NEW stat is for em. heat.) E = BROWN (Em. Heat, if you have it, i.e. electric resistance or gas) After you get the setup programming as a heat pump application, then wire it up this way and see if you get cooling. This really really depends on what your equipment is, so again, if you can provide the model #’s, I can get a schematic and attempt to decipher this. You’re not the first, and far from the last, who will have issues w/these stats. I do this for a living and i still have problems left & right. Hopefully, Xenos might just pop in and set the record straight once we get all the specs for the equipment. Don’t take my advice for gospel just yet since I really haven’t a clue as to what your equipment is designed to do. Having multiple stages can and will attribute to the problems you are having, in combination with the Stat itself not being setup for the EXACT heat pump combination. There are literally 10 different setup codes JUST for the Stat itself. I know I mentioned “7″, and I know i’m sounding like a skipping CD, so let’s get the models posted in order to figure out all of this. I’ll be around, so I’ll watch for ya.. This may or may not help, but I have the 7400 Installer Manual on my website at this link: Study it, figure out which is applicable to your system, and report back with the model #’s and everything you can possibly think of. I’m REALLY veering that the wiring aspect is not the culprit, but the programming of the computer- i mean Stat – is… If I am wrong on the assumption that code #7 for Install Setup “0170″, let me know. I wish I could just pop an answer out and make it all work for ya, but we’ve got some work to do… Like I said before, I do this for a living and this particular Stat is a thorn in my side. I’m not the only one who shares that opinion – there was a recent seminar in my area JUST for Honeywell’s new digital/touchscreen Stats… Even I had problems with MY OWN – and honestly, I got so irritate that while it DOES work as designed, i have yet to program the on/off/on/off times and all that!!! Go figure…. Niko Check your circuit breaker or fuses before calling for service – it could save you $$!! flheat “Re(4):Trane Baystat 239 to Honeywell RTH7400D” , posted Sat 28 May 13:49 ______________________________________________________________________ Ok first off I am an idiot. As a programmer and sys admin I should have known to RTFM. I am pretty sure all wiring is correct and etc. However I never programmed the digital box. After reading a reply I thought about it, and sure enough there is a entire section on it. So I wired the new one back up, programmed it, and voila. I got a digital thermostat, and my A/C is working. Thank god, I could not take my house being 85% again. Anyway still not exactly sure what I should do for X2? I have a aux spot still open on the new thermostat where X2 can be terminated. However X2 was jumpered off of W, and W is terminated at L now ? As for T it’s some outside temp thing I saw mentioned some where on the net. Guess Trane likes to use them. Thanks to all that helped, great site, resource, etc. Even for idiots like me. Guess when in doubt RTFM never fails ;) nchomeautomate “Re(5):Trane Baystat 239 to Honeywell RTH7400D” , posted Sat 9 Jun 16:20 ______________________________________________________________________ *sigh* I did exactly the same thing…suffered through heat when I was expecting cool with a Trane heat pump and a Honeywell RTH7400. …and I’m an electrical engineer and a programmer; who ever reads the manual? After a few hours, I even diagnosed my problem to the fact that the thermostat was energizing my “O” or “Orange” opposite of what I wanted. The thermostat was NOT energizing (applying 24 VAC) to my orange “O” wire when it wanted to cool, but that “told” my Trane to heat. It turns out, of course, that my thermostat was set not for heat pump operation at all. (Install setup code 0170 for my heat pump should have been “7″. It had defaulted to 1.) The question (for Honeywell) is this…If you force someone through an initial time and date setup, why would you NOT force them through the setting of the correct system type which is oh-so-critical? Ken at NC Home Automation Xenos Webmaster “Re(5):Trane Baystat 239 to Honeywell RTH7400D” , posted Sat 28 May 21:48 ______________________________________________________________________ T Brown is an out door anticipator not required on digital thermostats, so tape this off and X2 is emg heat. Xenos. The best way to escape a problem is to solve it. nchomeautomate “Re(6):Trane Baystat 239 to Honeywell RTH7400D” , posted Sat 9 Jun 16:27 ______________________________________________________________________ While trying to solve my other problem, I traced what “T” does. It appears that my old mechnical Trane thermostat takes the 24 VAC from “R”, runs it through the anticipator which adds just a little heat to the thermostat temperature-sensing coils, and then runs that signal outside through “T” for the outside unit to decide what further adjustments to make. Presumably, the outside unit allows more current (and therefore, turns off the heating sooner) when the outside temperature is warmer so you don’t overshoot as much. See for more details. Ken at NC Home Automation

Comments are closed.