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Why am I not getting hot water consistently from my new Marathon hot water heater?

Vonnie44 | Posted in Energy Efficiency and Durability on

I have a closed loop geothermal system with two 40 gallon hot water heaters. They were old and rusting so I replaced them both with just one 40 gallon Marathon hot water heater. I have not been able to get hot water when I need it all the time. Can someone please help me figure out why?

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  1. davidmeiland | | #1

    You mean the hot water runs out, or it's not always hot to begin with?

  2. kevin_in_denver | | #2

    The best place for water heater troubleshooting is definitely Water Heater Rescue:

  3. GBA Editor
    Martin Holladay | | #3

    Troubleshooting starts with the basics: have you verified that the electrical elements on the unit have power? Have you checked the aquastat (water temperature) setting on the water heater?

  4. Vonnie44 | | #4

    It is really puzzling as to when I have hot water. You would think it would be hot first thing in the morning but that is not always the case. Another example is last night I went to takeaway shower and it was tepid. One hour later, it was hot. It doesn't make any sense to me. I live alone and am very conscientious about water use because I am on a well. Before I changed out the two water heaters for the one Marathon, I had no trouble. It seems as if the cold is mixing with the hot and it comes out tepid. At other times, it is fine. Could it have something to do with how it is hooked to the geothermal unit? I don't know, I am just trying to run possibilities.

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