Thermostat/fan troubleshooting

Reply

  #1  
Old 12-02-18, 09:43 PM
Member
Thread Starter
Join Date: Dec 2002
Location: Houston, TX
Posts: 149
Upvotes: 0
Received 0 Votes on 0 Posts
Thermostat/fan troubleshooting

I have Honeywell T8000C thermostat. Not sure if I have fan problem or thermostat problem.

When I set thermostat to heat/auto-fan mode, I can hear the furnace turning on, thermostat shows the flame symbol, but no hot air is coming from the registers (even after waiting for 10 minutes).

When I set the the AC/auto-fan mode, I see the snowflake symbol, but no cold air coming from the registers. Outside unit does not turn on.

When I set Cool/Heat switch to OFF, and fan switch to ON, fan does not start (no air from registers).

The circulating fan does not turn on in either case. Do I have fan problem or is thermostat fan control/switch is bad?

How do I troubleshoot where/what the problem is?
 
Sponsored Links
  #2  
Old 12-02-18, 10:47 PM
PJmax's Avatar
Group Moderator
Join Date: Oct 2012
Location: Northern NJ - USA
Posts: 51,919
Received 260 Votes on 245 Posts
It's hard to say what the problem is because you not only don't have the blower coming on...... you don't have the outside unit coming on in A/C either. That indicates a problem a little more serious than just the blower.

Did you wait for 5 minutes when going to A/C mode ? The condenser has a 5 minute turn on delay.
If you check it again.... wait at least the 5 minutes for it to start. If it does.... you have just a blower problem.

If your blower is out..... that will take a meter to do some checking for power to the motor.
 
  #3  
Old 12-08-18, 10:06 AM
Member
Thread Starter
Join Date: Dec 2002
Location: Houston, TX
Posts: 149
Upvotes: 0
Received 0 Votes on 0 Posts
Thanks Pjmax. Here is what I did to troubleshoot....

I shorted G and R wires => fan did not start
I shorted W and R wires => furnace started
I shorted Y and G wires => outside compressor unit started.

I think the fan is busted. Any tips on troubleshooting the fan? Do I need to replace the fan or can it be repaired?
 
  #4  
Old 12-08-18, 10:32 AM
PJmax's Avatar
Group Moderator
Join Date: Oct 2012
Location: Northern NJ - USA
Posts: 51,919
Received 260 Votes on 245 Posts
It could be just a capacitor on the blower motor or the motor is bad or there is a problem with the control board. There's no guessing. You will need a meter to do testing.
 
Reply

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Thread Tools
Search this Thread
Display Modes
 
Ask a Question
Question Title:
Description:
Your question will be posted in: