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Hi I'm Brian and I'm here to help!
Can you please send me the model number of your old thermostat you are trying to get to work. Also what the make and type of ac and heat system you have? e.g. Carrier split system, Trane Heat pump split system etc...?
Great, thanks for that, and the model of the Honeywell thermostat model number?
Awesome, let me pull up the manual for your thermostat. It's possible the existing thermostat lost it's installer set up programming while it was uninstalled. Did you go back into installer set up and check the settings?
Ok thanks, ***** ***** saying the indoor blower operates when you set the thermostat fan mode from Auto to ON?
Also, if you made the request for a phone call from me, I currently don't have that option available. I apologize for the inconvenience.
Ok, let me bring up the manual. In the meantime, the default Honeywell installer setup password ***** ***** 4 digit date code that's on the back of the thermostat section when you pull it off the base.
If you can run the indoor blower with the fan mode switch on the thermostat, we should be ok. Give me a moment to review the installer set up settings. I'll be right back!
You're welcome! It took me a bit. It's been awhile since I worked on this thermostat. I believe I have the right manual for it. Do you have more than 2 wires or many wires connected at the thermostat?
Sorry I was reading the manual. This is a pretty complicated thermostat!
Oh, I wasn't to worried about whether you wired it right. I assumed that unless we figured out differently! I just wanted to know if the thermostat was communicating with another EIM module at the air handler or not and the amount of wires tells me! Ok scroll down to ISU 200 and tell me what it's set at in the installer set up?
Also, do you know if you have any Redlink devices in your system? like an outdoor sensor or remote control for the thermostat?
I'm sorry, I thought you were in the ISU already. Select installer setup.
Ok great! Scroll down to the ISU 200 first and that will tell us where we stand. Use Next or Back as you need to.
Yes, in the installer set up. You should see an ISU number on the screen and a selection value.
When you got into the installer set up it should have started at ISU 101 and pressing next should scroll to the next one.
Ah, select residential! Sorry.
Now use the up and down arrows next to the 101 to go to 200 and tell me what it says for 200
Awesome! what's it set at?
Perfect now go to 201 and what is that?
Perfect! now 206...
Perfect again! It didn't lose it's setup so now you can press Home or Done
Now you should go through the process of setting the date and time
You're very welcome! We'll figure it out! At the very worst there could be a blown fuse in your air handler but it doesn't seem like it! So now hit home and set the thermostat on cool and low enough to run. That's good that you changed the time a bit, it forces a restart!
Ok that is normal but only for 5 minutes. Can you change the fan mode switch to on and tell me if the indoor blower runs and you get airflow through your vents please?
Ok so the possibility is that since you saw that little spark, you may have blown a low voltage fuse on your air handler control board. Are you comfortable taking the blower panel off your air handler and looking on the control board for a 3 or 5 amp automotive style blade fuse?
That will probably take care of it. It appears your thermostat is fine! Trane is awful at posting their literature online so I don't have access to the service manual but if you give me the model number of the air handler, I'll see if by slight chance I can find it. Sometimes on certain models I get lucky and find one.
Turn the power off and look carefully at the fuse! Sometimes they don't look blown but they are!
Pull it out to look at it after you turn the power off!
I'm not sure what's up with that. That is odd indeed.
Ok, are there any led's lit on the board when the power is on?
Put the fuse back in if you haven't already. It's probably going to be easier to do the next test at the thermostat so button up the air handler, find a paperclip or little piece of wire you can bend into a U shape, go back to the thermostat, remove the face, and let's jumper between some of the terminals and see what happens.....
These jumper tests are going to be done with the air handler powered up. It's good if you have a helper to go look outside at the unit. First jumper R to G and tell me if the air handler blower runs. Don't worry about getting shocked, it's low voltage!
It may spark just a hair when you jumper them. Whatever you do, DON'T jump R to C at any time though!!!
And you're sure the fuse is ok and the power is on to the air handler? Do you by chance have a little multimeter?
Is there anything in the system I'm not aware of? Like a zoning panel or control panel next to the air handler?
Sorry, I should have asked that way early on!
Well, since the thermostat settings are ok and it keeps saying wait, that tells me there is no 24 volts coming into the thermostat. The 24 volts comes from the air handler and that's why we checked that fuse. If there is power to the air handler and the fuse is fine then the only thing left is either the 24 volt low voltage transformer or the control board in the air handler itself (which is very rare that shorting a wire would do that!) It's most likely the transformer. It will require taking some voltage readings in the air handler to confirm. If the transformer is blown on the low voltage side, it will still hum so that's not surprising you hear that.
I would certainly try replacing the fuse first though. I'm tellin ya they can fool ya! They've even fooled me on occasion! If you can get your hands on a meter we can check what's going on in the air handler but unfortunately short of changing the fuse, we've done everything we can do without a meter. FYI they are only about $20 at Wal Mart. Just sayin....
Yep, it's an ATC5 which you can find at wal mart or any auto parts store. I'll be online tomorrow so give me a shout on this same question and I'll get an email that you left a reply and I'll get back to you as soon as I can! I'm sorry we couldn't get it up and running tonight! At least you know more than you did and got a short lesson in ac low voltage wiring and thermostat setup! :P
Try to have a good night!
Good morning! I'm checking to see if you got your fuse replaced and if by chance you got your hands on a meter to see what's going on with your system?
Let me know how I can help,