Error Code 126 signifies inadequate communication between the thermostat and the furnace or AC unit. Consider turning off both the furnace and the AC, then powering them back on to …

Error 126 on the ComfortLink II thermostat indicates a communication fault between the thermostat and XL20i heat pump. Check the thermostat wiring connections for looseness or …

Hi! I have over 10 years of experience in HVAC, air conditioning, and refrigeration. Please read this entire post. I have worked on everything from 1200-ton chillers to residential ACs and …

I have a Trane AC System and am getting Error Code 126, followed by SOP 004.01 and CFG 001.04. I am quite handy and

An HVAC technician can assist with your Trane Comfortlink II thermostat displaying error code 126. How would you prefer to connect with the technician - via phone call or online chat?

Error code 126 on Trane Comfort Link ii. It is a 2009. The model is XL20i (not sure if that is the model) Started today.

The HVAC Technician can assist with your Trane thermostat error code 126 issue. How would you prefer to connect with the Technician - via phone call or online chat?

Error codes 126 and 89 on the Trane 4TEE3C0AA1000AA indicate communication failures between the thermostat and control board. Check the thermostat wiring for loose connections …

Nov 1, 2010 · New Trane XL20i with XC80 (installed about 6 months ago). Error code 126 appeared on the t-stat while cooling to 72 on a 95 degree day. I turned the...

New Trane XL20i with XC80 (installed about 6 months ago). Error code 126 appeared on the t-stat while cooling to 72 on a 95 degree day. I turned the breakers to the ...