# E2 code on Carrier OMTSTAT_3 thermostat



## Doc Holliday

Depends on the brand (and model) of thermostat.


----------



## hvactech126

if you have a owners manual it should explain E2 in the manual. This is what I found.....Brownout condition or too low of voltage to thermostat. Double check wiring and check for 24 vac between R and C. E2 will clear 15 sec after proper voltage is restored.

check you manual or post model number stat.


----------



## Doc Holliday

Can I ask if the reversing valve needing be energized during cooling mode could equate to not enough power as you suggested, tech?


----------



## hvactech126

it could be the reversing valve is bad and has a lot of resistance when power is applied causing the overall voltage to drop and cause the code. Yes that is possible. It could be many things such as the reversing valve sticking and causing a pressure switch to open. 

Here is a link to your homeowners guide...OMTSTAT 3


----------



## beenthere

tech126 is probably more familiar with your stat then I am. But I would check for loose or corroded wire connections at it and at the air handler and outdoor unit.

tehn if none were found, ohm out the contactor coil and RV coil(turn off line voltage first).


----------



## Doc Holliday

'Preciate it. Here's one on Totaline stats saying the stat is bad and to replace it on an E1 or E2 fault code. 

7. Replace your thermostat if you see an "E1" or "E2" error code on your screen. These codes appear when the sensor circuit is opened or shorted.


http://www.ehow.com/how_8062461_troubleshoot-totaline-programmable-thermostat.html​


----------



## hvactech126

Doc, the stat is a OMTSTAT 3 per the op subject line. The code refers to a low voltage situation.


----------



## Doc Holliday

I'm always learning, thanks.


----------



## hvactech126

Eagle, do as beenthere suggested and check all the wiring connections in stat, furnace, and HP first. Then check the resistance of the contactor and RV coil.

Also, add more info in a new post instead of updating your old post. It is hard to tell there is new info present unless watching closely.


----------



## strikeeagle

*First time user*

Sorry, I will start a new window the next time I add info. 

Mike


----------



## beenthere

Best to keep it all in one thread.


----------



## hvactech126

beenthere said:


> Best to keep it all in one thread.


Correct all the same thread just a new post.


----------



## strikeeagle

Got it. Same thread, new post.


----------

