Old panels gave 2.4v but this one gave 3.4v but so far it worked fine and sucked The fan seems to run faster. It was a tight fit as the original panels were about 49mm in area. I'm not sure if the extra volt will affect the temperature reading enough until warm weather sets in, but even in 40-degree weather the temperature jumps a few degrees when the weather station is in direct sunlight, and it doesn't matter. There seems to be a problem with these panels.