This water heater was probably not the OEM water heater that came with that unit. It probably replaced the original. Do you have manuals or receipts from the original owner? The Precisiontemp website has some good manuals available for download, and there is a troubleshooting guide for you to follow. The control circuit board has a red and green LED lights that will blink for certain trouble codes. I briefly glanced thru the manuals and did not see the location of the circuit board, so it must be inside the sheet metal box, possibly accessible thru the access panel on the side. (2nd pic)
I also found several YouTube videos about the unit. You should watch the installation video - very few things to hook up. I am not familiar with your unit but it is likely accessed by removing the bulkhead wall in your basement storage area - that is how I get to my Dometic IW60.
Here is a screen shot of the website and manuals available. There is a 2 year warranty to the original owner, but if you are within that 2 years they might help you with parts anyway.
MikenDebbie Aggie ‘77 in the sticks near Austin TX
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