About three weeks ago, I had a brand new Whirlpool 40 gal electric water heater installed. About a week later, I noticed brown rust colored water coming out of the hot water faucets when I turned on the water first thing in the morning after the heater had sat unused overnight about 8 hours. If I went out of town for a few days and the heater was sitting unused for a longer time, then the rust colored hot water would be a darker brown color.
The rust colored hot water flows for less than five seconds when the hot water first makes it to the faucet. The water then becomes clear after a few seconds. I first noticed this about a week after installation and this has continued happening for the last couple of weeks.
This happens in all the hot water faucets in the house. I had new expansion tank installed at same time. Any ideas?

Antb,
Is it possible that the water heater was installed with iron body fittings / connectors, or, was the wrong expansion tank installed? There are many types of expansion tanks, some are not rated for use with potable water systems.

Agree with Mike... probably the expansion tank! Read the label on the expansion tank. The label will clearly indicate if it is intended for potable water (clean water) or hydronic (heat) system. Obviously, your water heater should have the expansion tank for potable water! Post back with result, OK ?

Mark

The expansion tank says it is for potable water on the label. None of the new fittings appear to be iron body fittings. They are a chrome/stainless color. Any other ideas?

Any system left unused for a time will tend to have rust colored water at first use. If it turns clear after a flushing you are probably all right.

So my question would be is it your habit to leave the system shut down for days at a time? Also, have you had your water tested? I think Culligan does it for free.

Whole Home & Office Water Test | Water Quality Testing | Culligan

If nothing else eliminating the quality of the water as an issue is an important step in the resolution of your problem.

Antb,
We are assuming you have no issues with the cold water, and, that you have drained some water from the bottom of the water heater to check for discoloration. Any signs of iron in your toilet tanks?
The thermal expansion tanks have a stainless steel connector, and, the tank is coated with a corrosion proof epoxy. I would remove the tank, and operate with out it for a few days at lower temperatures - it is possible to have a defective tank.

Nothing but clear coming out of cold water line. And no signs in toilet.I ran it in a white bowl this morning,and what settles to the bottom is a copper color residue. I have a call into installer. Guess I will try to get them check it out. Thanks

I would suggest to call the installer or the Whirlpool water heater technical support at 877-817-6750 explain your problem they will advise you what to do, Thanks.

John