Upon arrival tech was thermostat was not working. Tech found VP8000 showing double dash on screen and error code indicating a faulty sensor. Tech pulled faceplate off wall and reinstalled which cleared error. Tech checked thermostat reading and is reading accurately. Gave system a cooling call and temperatures are within a good range. Tech made estimate to replace thermostat and customer wanted to wait for now. Informed customer that it could happen again and could not guarantee how long it would stay operational. Emailed estimate for new thermostat to customer. System is back operational for now.