Check the Water Heater Bypass Valve. It's located in the opening above your Propane tank, where the water pump resides. It's in one of your outside compartments. If you don't know where your Propane tank is located it's in the only outside compartment without a lock on the door's handle.
This is all covered in your Operator's Manual, in the Plumbing section #7, section 7-18.
Here's a screenshot of what to look for and what it should be set at: