why can’t you get hot water from a faucet when the freshwater supply is turned off, even though there’s a water heater full of water being heated and at the ready?

Question

why can’t you get hot water from a faucet when the freshwater supply is turned off, even though there’s a water heater full of water being heated and at the ready?

In: 1

Answer 1

I imagine the boiler has an automatic shutoff to prevent draining the boiler without fresh water coming in.

Or the heater doesn’t have a tank, and heats source water directly in real time.

Or is what you’re saying even correct?

Seriously, this isn’t an ELI5 question. This isn’t a complex problem to be answered simply. This is a simple question with a simple answer, but with a lot of missing information that you need to ask whoever services your water heater.