Typically, most manufacturers will suggest you put in new batteries for your thermostat every year. It would be best to do this before each Winter.
Many thermostats have indicators that display when your batteries are low. For those who don't, try changing batteries no less than once every 2 years. Often times batteries that are left inside of your thermostat for too long can leak and destroy it. It is much easier and more cost-effective to maintain fresh batteries than to replace a broken thermostat.
If you're in need of repairs or maintenance for your home air conditioning and heating system, call AC Express right away! Our certified technicians can respond same-day. Call now! (512) 866-5520