Water Heaters - Turn off hot water

Hi everyone,

I would like to get a confirmation for this.

I want to take an existing hot water line which goes to my washing machine and split it in two so that I can connect a hot water faucet in my garage on the other side of the wall. I've looked on this site and some other sites and found the way to do it (I've got no experience in plumbing...), my pipe is in PEX so no soldering will be necessary and it seems pretty easy.

The problem is that to cut the existing pipe, I need the hot water to be turned off, of course. I thought there would be a valve I could shut off on the pipe right after it leaves the water heater, there isn't.

What I'd like to know: can I just turn off the cold water (in) valve, which would kill the water pressure after a little while while keeping the tank mostly full? Should I turn off the water heater completely (gas)? Will I have to purge the water tank?

I know there might be some pressure issues so I just want to hear something from someone who knows that!

Thanks!

Water heaters rarely have valves on their outlets so it is just as you thought, turn off the cold water supply and then relieve the pressure by opening a hot water faucet.

Turning the combination gas valve from ON to PILOT should be just fine for the time necessary to accomplish the work. I assume that you have the proper tools for working with PEX or are planning on using Shark-Bite fittings. You might want to work from the new faucet in the garage back to the connection point next to your laundry, that way you will only need to have the water off for a short time while you cut and fit the tee section.

After you finish the piping turn the cold water supply to the water heater back on, bleed all the air from the new piping and check for leaks. If there are no leaks then turn the combination gas valve from pilot back to on.

Thanks for the reply.


My gas heater only has an on/off switch, no pilot (well I cannot set it to pilot). I'll follow the instructions that came with it and turn it off, but it should only take me a few minutes to do the fittings.

Thanks again!

Update:

I rented a professional tool for $12 (the cheap tool at the hardware store was $54...) and it was the easiest job I've ever done. Long live Pex pipes!