How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site.
    Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask airheatman Your Own Question
airheatman
airheatman, HVAC Technician
Category: HVAC
Satisfied Customers: 7776
Experience:  Furnace, A/C and heat pump specialist.
16514686
Type Your HVAC Question Here...
airheatman is online now
A new question is answered every 9 seconds

Just replaced the motor and capacitor in my trane xr80. But

Customer Question

Hello...just replaced the motor and capacitor in my trane xr80. But the fan will not come on, whether i set it to cool or just fan. I bypassed connected the motor black wire to the door switch wire just to see if it works, and it spins up fine. I am assuming i have a bad board...would you agree?
JA: I'll do all I can to help. How long have you been dealing with this?
Customer: my motor siezed up on Saturday...just got the new motor today
JA: Do you plan on doing the work yourself?
Customer: already am....the new motor and capcitor is installed
JA: Anything else we should know to help you best?
Customer: it has been 100 degrees out every day...i need to get the fan running, if only temporarily, to cool the house down
Submitted: 4 months ago.
Category: HVAC
Expert:  airheatman replied 4 months ago.

1.Do you have a meter for troubleshooting?

2. Give me complete model on furnace from label inside (Something like TUD08E

3.Tell me where you have fan wires connected on board

Customer: replied 4 months ago.
tud1b080a9481aa......I took pictures of the wires before I took the old motor out and replaced them exactly the same....Black=cool, blue =heat, red and yellow are park....white I could not read the text...but is on the same terminal
Customer: replied 4 months ago.
I can send pictures if it helps...
I do have a meter if I need it...
Expert:  airheatman replied 4 months ago.

Let's do this. Turn thermostat to COOL. Take the meter and check between the Black COOL terminal and WHite NEUTRAL and verify we are sending 120v to motor. (Door switch will have to be held in of course)

Customer: replied 4 months ago.
with the fan on auto and the thermostat on cool I measured no power
Expert:  airheatman replied 4 months ago.

Door switch IN?

Customer: replied 4 months ago.
I had the door switch depressed...
Customer: replied 4 months ago.
yup
Expert:  airheatman replied 4 months ago.

OK does outdoor unit come on?

Customer: replied 4 months ago.
it is not on....wait...let me try again
Customer: replied 4 months ago.
no, it did not come on
Customer: replied 4 months ago.
it confused me because it was coming on this past saturday when I discovered the bad motor
Expert:  airheatman replied 4 months ago.

Check the little fuse on the furnace board and make sure it is not blown

http://i.imgur.com/kYe4Epz.png

Customer: replied 4 months ago.
the fuse is good
Expert:  airheatman replied 4 months ago.

Next check for 120v into transformer from XFMR terminals and then 24v out of transformer

Customer: replied 4 months ago.
ok...be right back
Expert:  airheatman replied 4 months ago.

Take your time

Customer: replied 4 months ago.
transformer is good
Expert:  airheatman replied 4 months ago.

OK lets do this next. On furnace board, connect the R to G where thermostat wires hook up and see if blower comes on

Customer: replied 4 months ago.
you want me to disconnect both and connect the red wire to the green terminal and let the green wire hang? Just clarifying...
Expert:  airheatman replied 4 months ago.

You can leave wires connected. Use a jumper or a pair of needle nose pliers to touch R terminal to G terminal (Door switch IN)

Customer: replied 4 months ago.
nothing changed
Expert:  airheatman replied 4 months ago.

OK if we have 120v into transformer, 24v out of transformer but no blower with R and G connected an no outdoor unit on call for cool with fuse intact you have a bad board.

Customer: replied 4 months ago.
I was afraid of that....is there any way to force the ac to turn on or even just the fan until I can get a new board in?
Customer: replied 4 months ago.
do you have the pn of the board?
Expert:  airheatman replied 4 months ago.

You can connect the black fan wire to the XMFR to pick up power but it will run nonstop.

Expert:  airheatman replied 4 months ago.

Part #CNT05165

If you have further questions, please let me know.

Thanks for letting me work with you.If my answer has been polite, professional,and thorough, please click one of the ratings before you go. If you still need help let me know!.Expert is not paid for assisting you until you rate answer.Feel free to follow up for 30 days at no additional cost. Bonus always appreciated if you feel justified.

To rate answer, please select one of the stars on the page.

Related HVAC Questions