furnace blower starts on its own?

[nunya]

Did this twice, turned off furnace, did reset on thermostat, reads EE, did the phone cord plugged into wall jack check for DC for communication, have DC there and everywhere......no flashing red light on the furnace board, DC power. How bout if the relay shorted on the board???? Replaced thermostat already.....still EE. Just checkin to see if this happened to anyone else??? Thanks.

[ckwizard]

Check for moisture or a water leak around the furnace, that would cause it to turn on.

[rohrmann]

EE is lack of communication to the first A/C, which can be a bad cable or a bad connection at the box in the A/C which is zone #1, if you have two A/C's. The heater control is run to the main A/C control box, which is why the heater is shown as zone #1. I had to replace our control box on #2 A/C due to severe corrosion to not only the circuit board, but also to the phone jacks on the board. You can access the box above the return filter on the A/C. On line, the box only cost $100, delivered, and was fairly simple to replace, assuming it is the culprit.

[nunya]

I have cleaned and checked connections in the A/C and have power to the thermostat, did checks I could find on websites??? Asking the experts now. Thanks for response, will look more.

[wjwheeler]

My furnace would start on its own. I found a water leak dripping on the furnace control board (mounted on the furnace). I dried it off, fixed the leak and solved the problem.

[Ozz]

nunya, sounds like a bad board, you probably nailed it with a stuck relay on the board. I have smacked them with a screwdriver handle before and un-stuck them, but you might as well order another board. With the integrated circuit board on the A/C and the funky thermostat inter-action, it is just a WAG on the troubleshooting. Them little 1's and 0's give us troubleshooters a fit.
Good luck on it.
I have you on my short list on people I want to visit, we will be on the road one day... 367 days... 3 hrs and 15 minutes, but who's counting...

[nunya]

Ozz, thanks for the response, I was hopin you would see this post. I think I will just get the board and change it like you suggested. I have no reason to not believe that its something else from testing I have done and researched. Would love to meet you for sure! We will be headin to Yuma for winter next month. Thanks again Ozz.

[nunya]

Problem solved, with the help of RV tech Jason Wiggers from Accurate RV, based in Yuma and Bend Oregon!! Great guy to deal with, highly recommend. Replaced board in #1 AC and had to replace phone cord for communications, pulling new thru the roof was fun! All works great and ready for the increasing heat here in Yuma. Learned a lot from this journey!!

[DQDick]

Accurate RV did a great job for a friend of ours also. Great knowledgeable folks and reasonable pricing.

[nunya]

I fully agree!! would recommend to all