supply line

I'm trying to find out if I need a check valve on my cold water supply line to my water heater. I have a tankless water heater, 2 gal expansion tank, and a separate recirculating pump. I had to replace part of my stack that cracked and noticed a check valve on the cold water supply that feeds...

We have these shut off valves (shown in pic). I need to change my faucet. How do I remove the supply line from the shut off valve?

I have a pinhole leak in the cold water supply line to my hot water heater. Not my area of expertise. Apparently it's soldered to the wall connection. Quote from plumber to replace both the cold water supply line as well as the hot water out line, and doing so with the standard threaded...

I am making a heat exchanger for my shower trap arm. I have a 2" section of copper drain pipe that I want to coil the incoming water supply line around, before the supply feeds into the 3/4" inlet of my on-demand water heater. I already tried and failed at coiling 3/4" soft copper tubing around...

Hi everyone. I’m hoping someone can help me identify what the following connector is called. It goes to a bath sink and connects from the widespread handle stem to the center faucet stem. This connector connects to the handle stem. Hoping to find a replacement.

I was reading a plumbing article earlier today and it had this photo in it. It looks as if it’s a pex supply line with a push fitting at the end. Are these type of supply lines allowed? I’m curious because I can no longer purchase the hand tight only sink supply lines at my local hardware store...