Home>Discussions>PLUMBING>Hot water turns cold in kitchen after bathroom toilet is flushed
6 posts / 0 new
Last post
hotcold07
Hot water turns cold in kitchen after bathroom toilet is flushed

When warm water is being used in the kitchen sink, and someone flushes the toilet in the bathroom all of the warm water coming out of the kitchen sink becomes cold water, in our house.

We have replaced the water heater 3 times and it failed to correct the problem. We have consulted with two different plumbers one from Quality Plumbing located in Sioux City, Iowa and another one from Morningside Plumbing also from Sioux City, Iowa and none of them have any idea as to how to correct the issue or why the water turns ice cold after the toilet is flushed.

The problem started 5 to 10 years ago. The original water heater did not produce this problem.
The water heater is a 40 gallon natural gas fired water heater made by A. O. Smith.

Do you have any ideas that might correct the problem once and for all?

The home owners are the 1st and only owners of this house since it was built in 1966.

Thank you

goldhiller
Re: Hot water turns cold in kitchen after bathroom toilet is flushed

A 'first" question........

Has anyone checked if this toilet's tank is refilling with hot water rather than cold water?

hotcold07
Re: Hot water turns cold in kitchen after bathroom toilet is flushed

Yes,

The toilet is filling with cold water.

All of the hot and most of the cold water in the house also comes from a salt fed soft water system including the bathroom toilet, kitchen and bath sinks, tub shower combo, dishwasher, sink hot water is soft and the cold water is hard.

goldhiller
Re: Hot water turns cold in kitchen after bathroom toilet is flushed

Okay.

I have theory in mind, but before I devote the time to discussing it, could you tell me this.....

When the problem occurs at the kitchen sink, what happens if you turn the faucet to the "hot only" position.........(whether a two-handled faucet or a single-handled faucet.) Does any water flow in "hot only" or is there no water?

And.....did this problem occur immediately after the orginal WH was replaced with a new one?

hotcold07
Re: Hot water turns cold in kitchen after bathroom toilet is flushed

The kitchen faucet is a single lever American Standard that was installed in August 2007.

Even with the lever placed in the far left position for hot water only cold water flows from the kitchen faucet regardlesss of where the faucet handle's position after either the toilet is flushed or if someone washes their hands in the bathroom sink with warm water. All of the hot water in the house is soft and most of the cold except for the kitchen sink and out side water spots which have hard water only.

After the toilet refils with cold soft water then hot water comes out of the kitchen faucet again.

The problem first occurred after the original water heater was replaced 20 years ago.

Thank you

hotcold07
Re: Hot water turns cold in kitchen after bathroom toilet is flushed

To answer some of your questions:

I could be off on the number of years the problem has occurred, my dad passed away unexpectedly before my post, may have affected my recollection of when the problem began.

The hot water heater's tanks rust and leak they are fed by natural gas. The last one rusted through last year it was replaced under the manufacturers warranty it is an A. O. Smith water heater.

Both the kitchen and bathroom sink faucets are single lever. The faucets were originally had seperate valves for hot and cold water and were replaced with single lever models in the mid 1976 by my parents.

The bath tub has seperate hot and cold valves.

The original water softener was replaced in the late 1990's because the metal tank cylinder that the controls are attach too rusted out and leaked water all over the basement. The current tank is a sprial wound fiberglass, the salt reservior tank and controller were also replaced at the same time.

Hot water from the bath tub or shower which is soft water also turns ice cold if the toilet is flushed.

Reason for the cold water in the kitchen not being software is to provide better tasteing drinking water. When the house was built in 1966 the contractor believed no one should drink soft water.
Our refrigerator uses hard water

No back flow preventers have been installed in any of the homes built by the contractor Ken Burris in the 1960's through the mid 1970's. I have not found any pressure reducing valves installed in the plumbing system. The house has water shut off valves installed below the kitchen sink on the supply lines, about the water heater, and a cheap pin shut off valve installed on the cold water supply to the refrigerator cold water line. My dad installed another water shut off valve below the toilet in the bathroom in 1996 when he replaced the toilet. Old fashioned shut off valves installed above the clothes washer supply lines.

Thank you for your assistance.

Sponsored Stories

TV Listings

Find TV listings for This Old House and Ask This Old House in your area.