I have a question I am hoping someone can help me with. I had a 50 gallon (40K BTU) AO Smith water heater for about 10 years. In the past few months it was not producing enough how water for more than one person, but, before that we had no issues with my wife and I taking back to back showers. So, I decided to replace the tank with a new one that I bought from Home Depot. It is a GE 50 gallon tank (made by Rheem - GG50T06AVH00 - 38K BTH 50). However, I am finding that the tank is acting in a very similar way in the sense that it cannot produce enough hot water for back to back showers.
I called GE and they told me my expectations are too high? According to them a hot water tank is only partially hot water (which I get) and I forget the amount quoted, but I think the hot water content was something like 35 gallons (so, say 70% of the total). So, by their calc with my showhead putting out about 3 gpm. I could only count on 10 to 12 minutes of hot water. Of course this has to be wrong give the 35 gallons are heated well beyond what anyone would shower at (we set the dial between A and B - I forget the exact temp range but the water at the highest temp is very hot).
One other thing I had heard from GE is that our groundwater is cold here (just outside of Chicago). But we have the issue regardless of outside temp.
GE has offered to send someone out (at a cost if they find no issue) but they assure me that nothing is wrong.
I am wondering if anyone can help me with the following questions:
1. Could anything outside of the hot water heater be at play? We did a bathroom remodel and replaced the shower hardware (including a new value etc). There was no immediate issue after the remodel, but, I thought I would throw that out there as we had seen something similar with both water heaters. We did check both the kitchen and shower and temps are the same.
2. Is there a real calculation that I can use to figure out how many minutes of hot water I can expect? If not, does anyone have any real world experience with this water heater or any 50 gallon water heater that they can share? Given my experience with the AO Smith this water heater is not working correctly.