TRANE ComfortLink II XL1050 , TZON1050AC52ZA
THE XL950 IS OBSOLETE AND DISCONTINUED.REPLACED BY THE XL1050. This is not just a thermostat. It’s an energy command center. If you are unsure how to fix it.call a Professional! Replaces / Supersedes: CNT06390, CNT-6390, TZON1050AC52Z, TZONE950AC522, TZONE950AC52Z and others.