GLD to get rid of it

We are returning the GE GLD4400NWW after running it 6 times for 2 loads of unclean dishes. We installed it ran it 3 times to try and get 1 load of dishes clean. We called the GE service center who came out 2 weeks later to tell me I needed to increase the temperature of my hot water heater to activate the dishwasher detergent since the newer ones use less water. So we have to waste energy on the hot water heater 24/7 instead using more water. Which is worse? It seems like a bigger waste to have to keep the water heater at 140 degrees all the time than to use a few more gallons of water 2 times a week. So we increased the temp on the water heater even though we do not like our hot water that hot (140 degrees) when we had it set at 120 for 10 years with no problems with the old builder model (GE). Then we ran it 3 more times on the another load and still no clean dishes. I have ordered a Whirlpool so we'll see if it works any better.