Heating & Cooling Logo

Related Topics:

Posted on May 29, 2008
Answered by a Fixya Expert

Trustworthy Expert Solutions

At Fixya.com, our trusted experts are meticulously vetted and possess extensive experience in their respective fields. Backed by a community of knowledgeable professionals, our platform ensures that the solutions provided are thoroughly researched and validated.

View Our Top Experts

I have a Honeywell T8131C programmable thermostat. Our power went out yesterday, and now the "Bat Lo" won't go away. We replaced the batteries, but the "Bat Lo" indicator stayed on even after changing to new batteries. As per the troubleshooting guide, we took them out, waited an hour, and then reinstalled new batteries. Still, the "Bat Lo" indicator is still on. How do I get it to go away because I can't adjust the thermostat with it that way?

  • Anonymous Mar 29, 2009

    I tried sticking the batterries in reverse polarity, but it did not work.

  • cz8729 Apr 12, 2009

    I have the same problem and tried the reverse battery trik, it did not work.



    There is catch though, when I switched the palarity and put the batteries in, the power was always on, even I put the second switch on the right on off position. Did I do any thing wrong?



    I had never had the unit cycling through any checking. Maybe there is a problem right there. How to turn it off completely? The thing is installed on the wall and even you un-plug the battery, it operates on the AC power of its own. Maybe I should shut down the power of whole house, huh?



    Thanks.

×

5 Answers

Anonymous

Level 1:

An expert who has achieved level 1.

Corporal:

An expert that has over 10 points.

Mayor:

An expert whose answer got voted for 2 times.

  • Contributor 1 Answer
  • Posted on Apr 22, 2009
Anonymous
Contributor
Level 1:

An expert who has achieved level 1.

Corporal:

An expert that has over 10 points.

Mayor:

An expert whose answer got voted for 2 times.

Joined: Apr 22, 2009
Answers
1
Questions
0
Helped
3191
Points
11

I tried all the tricks mentioned previously to no avail.

These are the steps I performed to get it to work:

1. Remove batteries and make sure the battery contacts inside the unit are clean.

2. Disconnect all the wires from the back of the unit. Be careful not let any of the bare wire ends to come in contact with each other. Make sure you mark the wires or verify that the color code matches the markings on the rear cover:
W=White wire;
Y=Yellow wire;
G=Green wire;
R=Red wire (low voltage DC); and
C=Common (wire color varies)

3. Leave the unit disconnected with batteries removed for about an hour to make sure all the memory drains. I waited an hour, but it may not require that much time.

4. Install the batteries in the correct positions per the instructions. The unit should perform a power up display test, then the display will flash the time and temperature.

5. Set the clock and the display will stop flashing.

6. Slide the switch to cool and/or heat and program the desired weekday/weekend settings.

7. Slide the switch back to off once all weekday/weekend settings are made.

8. Reconnect the wires that were removed in step 2.

9. System should be operational at this time.

  • TexFix Nov 30, 2010

    This took about 30 minutes for the memory to clear. This process also works if you re-wire the unit back in first, then re-insert the batteries in their normal orientation. After that, you can then set the clock and the display will stop flashing. Finally, you can re-program all the settings you may need. Enjoy....

  • LuckySuperMommy
    LuckySuperMommy Mar 26, 2014

    I had the same problem after a power outage. I essentially did the same thing to fix it, but instead of re-wiring, I just cut the power to the thermostat by removing the batteries and turning off the power at the breaker box to the unit. I waited about 30 minutes then put the batteries back in, set the day and time, and then restored power. That fixed the problem.

×

Anonymous

Level 1:

An expert who has achieved level 1.

Mayor:

An expert whose answer got voted for 2 times.

  • Contributor 1 Answer
  • Posted on Dec 10, 2008
Anonymous
Contributor
Level 1:

An expert who has achieved level 1.

Mayor:

An expert whose answer got voted for 2 times.

Joined: Dec 10, 2008
Answers
1
Questions
0
Helped
3191
Points
3

I spoke to Honeywell...the fix is really quite simple! They asked me to clean the metal battery posts (in case there was corrsion). That didn't fix my problem b/c I had cleaned the corrosion previously. Next, the guy had me insert new batteries in REVERSE polarity and leave the unit in the off position for 10 seconds. He then had me take the batteries out and insert them in the correct polarity.

The unit cycled through its checks and worked perfectly!

Easy fix. Hope this helps someone else!

Skeetman

  • Anonymous Jul 06, 2012

    Thanks for the advice! I had the same problem with my Honeywell thermostat! Thank God I did not need to go through all the trouble of rewiring it. All I need to do was to clean the corroded battery posts then put in new batteries and voila! It's working good now!

×

Ad

Anonymous

Level 1:

An expert who has achieved level 1.

  • Contributor 1 Answer
  • Posted on Sep 20, 2009
Anonymous
Contributor
Level 1:

An expert who has achieved level 1.

Joined: Sep 20, 2009
Answers
1
Questions
0
Helped
3191
Points
2

I tryed the timdmurphy advice of unhooking the cables and I waited 20 mins and it was gone.
Do not buy a new thermostat before trying this one

Anonymous

Level 3:

An expert who has achieved level 3 by getting 1000 points

All-Star:

An expert that got 10 achievements.

MVP:

An expert that got 5 achievements.

Vice President:

An expert whose answer got voted for 100 times.

  • Master 828 Answers
  • Posted on May 29, 2008
Anonymous
Master
Level 3:

An expert who has achieved level 3 by getting 1000 points

All-Star:

An expert that got 10 achievements.

MVP:

An expert that got 5 achievements.

Vice President:

An expert whose answer got voted for 100 times.

Joined: Apr 28, 2008
Answers
828
Questions
0
Helped
454881
Points
1944

Replace the thermostat.

Anonymous

Level 1:

An expert who has achieved level 1.

  • Contributor 1 Answer
  • Posted on Jan 10, 2013
Anonymous
Contributor
Level 1:

An expert who has achieved level 1.

Joined: Jan 10, 2013
Answers
1
Questions
0
Helped
3191
Points
0

I have a Honeywell T8131C thermostat and I set it to come on at 6;00 in the morning to come on but it does not come on what is my problem

Add Your Answer

×

Uploading: 0%

my-video-file.mp4

Complete. Click "Add" to insert your video. Add

×

Loading...
Loading...

Related Questions:

1helpful
1answer

Honeywell non-programmable thermostat. LO appears in window

Are there buttons on the unit? If so depress the 2 outer buttons and hold for 5 seconds...should go away and run now.
5helpful
2answers

My beutler 800 said lo bat we replaced them and still reads bat lo

The other "solution" posted here is not a solution. According to this web site: http://www.espenergy.com/faq_honeywell_thermostat.htm


First, replace the batteries with a new set of AA alkaline batteries. If you insert the new batteries within 20 to 30 seconds of removing the old ones, you will not have to reprogram the thermostat. If the bAt Lo indication does not clear itself once new batteries are placed in the device install the batteries backward for 5 seconds, take them out, and reinstall correctly.

So I tried it... put the batteries in backwards. It completely reset the thermostat so I had to reprogram it (which was easy enough). One thing I did that the instructions did not specify. After I removed the batteries, I let it go completely blank before installing them backwards. Then I waited 5 seconds, pulled em out and put them back in correctly and eventually it started flashing indicating it needed to be programmed. HINT: Don't forget to set the current time!
10helpful
2answers

Even after replacing the battery, the programmable Honeywell thermostat still shows "Low Batt."

Turn control to off. Remove the batteries for at least one hour. If the display message still reads "bat lo", leave control off, batteries out, and disconnect the red wire on back and wait another hour. Reconnect red wire, put new batteries in and turn system on. It's like a reboot.
5helpful
1answer

Bat lo flashing periodically

You need to change batteries. The bat lo light flashes when you have about 10% battery life left. Rus
0helpful
1answer

The bat lo message will not go away even after replacing batteries.. No functions either

One thing you might want to try is to remove the batteries and wait for a few minutes until everything clears. It could take around 10 minutes or so. This will reset the thermostat. Also look on the back and/or on the board of the thermostat to see if there is a reset button.

I hope this helps! :)
9helpful
1answer

6AE Lo

6AE Lo is probably 'bAt Lo'. Batteries are low and need to be replaced.  It looks like 6AE Lo because of the digital readout (b looks like 6).

http://www.espenergy.com/faq_honeywell_thermostat.htm

Model number shouldn't change what the readout means.
14helpful
4answers

I replaced the batteries in my Honeywell CT3300 and the "Bat Lo" message won't go away even with fresh batteries. Is there a reset button or something?

Per manual do this: System set to Off Remove batterie Replace IN REVERSE POLARITY POSITION or 5-10 seconds Put back in with CORRECT POLARITY Reprogram per sticker on back of thermostat. Done. Just did this myself and it's simple and effective! PaulHaven
0helpful
1answer

My honeywell theromstat keeps displaying repl bat

Have you checked to make sure the batteries are, in fact, good and that they are facing the right way? If so, it's time for a new thermostat.
0helpful
1answer

Programmable A/C thermostat has power but shows no temp.

Check power totast. Float switch sometomes kills power to stat. Check drain.
Not finding what you are looking for?

3,201 views

Ask a Question

Usually answered in minutes!

Top Heating & Cooling Experts

Paul Carew

Level 3 Expert

3808 Answers

john h

Level 3 Expert

29494 Answers

Brad Brown

Level 3 Expert

19187 Answers

Are you a Heating and Cooling Expert? Answer questions, earn points and help others

Answer questions

Manuals & User Guides

Loading...