No water in house yet water main to house okay

usually there is also a main water valve where the water enters the house. often times just below an outside faucet on the front of your house. or if you live in a part of the world that freezes during winter, the valve may be in a laundry room or where the water heater is located. good luck.

Have you checked the main water line at the water meter? If your on a well have you checked the breaker to the well pump?

Shut off unit then turn off water to house at water main out side. Drain water heater remove old valve install new

1. Are you on mains pressure2. Is the problem new. ( was it working once)If Yes could be a stuck HW washer.

Why did it fail? How did it fail? Was it the plumbing that failed? Replace it with a Pentair filter housing, 10" housing, 20" housing or Big Blue housing and make sure it is plumbed in properly. It is very unusual for a filter housing to fail unless it freezes up.
RJ

These heaters are an instaneous heater. Check the power supply at the switchboard. If okay the most obvious problem will be a blown/faulty element.

On my NPE-210S you need to switch dipswitch #4 to the "on" position, or up on mine. Dip switches are found behind the main panel on the control board. you'll have to also open up the plastic case housing the control board. 4 screws for the main panel and 4 screws for the control board housing.

Centre tap of the rinnai will turn off hot water supply only.
Easiest way is to turn off your mains water supply. This will isolate both hot and cold, no need to turn off anything else

Brian,

I would try to tighten it up without putting tape on it. The ring will compress into pipe when you tighten it to form a seal.
If then it try's to leak you may apply tape or a paste type sealant to stop drip.

that is a coupler that is inside the propeller housing easy to replace.are you replacing motor only or complete pump and what brands