There's actually no plumbing code (checks) for my house. I could drop my poop right out the back of the house and pull my water through lead pipes from a mosquito swamp into my sink. As long as it is immediately heated it is fine. It is literally the only requirement.

My permit explicitly says they will check absolutely nothing but how far the house is from the property line and that I have immediate hot water.

Haha that’s crazy, there has to be someone with a financial interest in instant hot water heaters making bank from that. If it was conservation they’d mandate ultra low flow toilets and other water saving measures. Is this a township or similar level of government?