water heater?

Looking for some help. Installed a 50 gal. power vented water heater in 08. Worked great for about a year and then the relief valve started going off. Thought it might be the relief valve so I replaced. Didn’t help. Talked to place that I purchased it from and they said that I needed to installed a tank. So I did and everything was fine for about a year. Then the relief valve started going off again. Called the company, American Water Heaters, and they said the tank was probably not pressurized correctly. So I checked, 60 lbs and 60 lbs of H2O pressure in the house. Called them back and the person I talked to this time said that since the temp was 145 degrees and I had the thermostat set one notch above the vacation mode that it was probably the thermostat. So I replace yesterday and went down stairs today and it still discharged something overnight or this a.m. I checked the temp and it is at 125 degress. I am going to call the company tomorrow since the warranty part they sent did not fix the problem. I am getting tired of drying my basement out. Anyone have any ideas as to what it could be or what I need to ask the company. Thanks in advance for your help. in SD. Todd

Have you Googled it? I had a American Water Heater professionally installed about the same time by O’connor plumbing and heating. It failed in 13 months. One month after the warrenty! Simply amazing.

I have seen the same thing. Changed out a gas control and burner for a customer with a American heater that was doing the same thing. New parts did the same thing. If its under warranty try to get some money out of them and put it towards a different water heater.