A year ago, I had a brand new smart thermostat that caused the A/C fuse to keep blowing. I replaced the thermostat with a duplicate, swapped the fuse out and everything has been fine. Now a year later, my AC fuse again blew. I checked the thermostat on another ac in the house and it blew that fuse too. I replaced both fuses. Now the AC with the problem will not supply any power out of the 24v side of the transformer, as tested with a multimeter. I've ordered a new transformer and a replacement thermostat for the third time.
Is it coincidence it's the same unit and I've now had 2 bad thermostats? It is possible the transformer has been bad this whole time and finally gave out, taking the thermostat with it? This AC is not even 2 years old but the company that installed it is pretty poor and won't stand behind their install.