Never heard of a dish washer that takes 2 1/2 hours. I do NOT use the heat dry element. I just open the door a tad.
My old one did. The new one we purchased this summer is much quieter and takes about half the time.
I have a brand new one. Just set it for heavy duty, hot wash, steam and dry. 3 hours and 25 minutes for that cycle. Stupid thing won’t even dry them all the way. But it meets all the energy standards. Stupid!!!