washing machine hookup to cold water - where?

Question

I had a plumber run plumbing for a washing machine.  He hooked up the supply lines about 7 inches above the water heater in the basement - hot water ties in 7" above water heater output, and cold water supply ties in about 7" above the intake to the water heater.

Now, when I turn on my kitchen faucet directly above the water heater, the cold water runs hot for a few seconds before it turns cold.  The plumber says that's because I'm getting the 7 inches of heated water  between the water heater and the cold water line.    Which I guess makes sense ... but if that's the case, why didn't the cold water run hot for a few seconds before that?  Why have I never in my life noticed this issue from any faucet in my house, a public bathroom, etc?

Is it ok for him to have tied in the water there?  Or should he have tied in somewhere else?

Thank you.

Laura Turner · Answer

Thanks for the answers.  It just seems weird that a washer hookup downstairs would affect a sink upstairs.  But if there's no need to worry, I won't.

Mike Baker · Answer

I'm curious if he hooked it up there because it was the easiest spot?

It's not a big deal to hook it there, and everything will operate just fine. The reason you haven't come across the problem is that it's not a common problem. It happens sometimes and it's nothing to be alarmed about.

Your faucet also has to evacuate the standing water in the pipe before it gets to the water from the "hot point" of the pipe. That's why it's cool for a second and then hot and then cool again.

You could have him move it, but it won't affect anything negatively if you leave it there either.

Laura Turner · Answer

Yes of course, that's what's happening.

My question is, is this placement of the washing machine cold water tap ok?  And why did he do it that way?  As I've never had an issue with the cold water running hot for a bit in any of my houses or any other place, it just seems a bit strange.

Larry P. · Answer

Is it possible that the cold water in the line coming off of the intake to the water heater is being heated by the heat of the water heater rising up?  If so maybe the cold water line can be repositioned where the heat from the water heater dos not rise up and heat it up.