Dishwasher won't stop filling up

[louie]

Hi There. I have a whirlpool under counter dishwasher. Noticed this morning it was filled insidefull of water. It did not flood the floors however we had to jig the cycle to go to the draining cycle to get rid of the water. All the water was drained.
After about 2 hours, I went to put some dishes in there and it was full of water again. The dishwasher was not even turned on. After some looking around I noticed that on the left hand side of the dishwasher there was a hole with warm water leaking from it. I doublechecked to make sure the d/w was not in the middle of any cycle....only when I turned off the hot water valve under my sink did the leaking water inside the d/w stop. I turn the valve back on, and the water starts to leak again.

Does anyone know how to fix this?

I live in a condo, so I guess it is a standard set up. There is no "airgap" on my sink. Not sure if this helps. There is also a red handle on the pipe that leads fro m the hot water pipe to the dishwasher. I tried to move it but it doesn't budge but a couple of centimeters, and this didn;t stop the leak either (but I am sure I am not moving it enough - wonder if there is a trick to it??)

Help!!!

[HayZee518]

sounds like the water solenoid is faulty. the valve is staying open. in back of the lower front panel near the front you'll see a copper tubing going into a blue or green plastic solenoid with two wires going to it. this is the water solenoid. inside is a steel slug that moves to open the water feed. your's it seems is stuck open. time for a new valve. go to this site and find your dishwasher and its parts list. www dot repairclinic dot com - valve is probably held in place with two hex shaped screws underneath or on the left hand panel.

[LazyPup]

Dishwashers use an inverted cup float to measure the water level in the tub.

The tub has a tube extending up from the bottom that serves as a standpipe. The inverted cup has a rod that goes down through that tube and rests on a cam from the water level micro-switch. As water enters the tub air is trapped inside the inverted cup and the cup floats upwards as the water rises. In turn the rod rises and allows the cam on the microswitch to rise also. When the tub reaches its preset limit the float has risen high enough to allow the microswitch to open, which in turn closes the solenoid water valve turning the water off.

Often the shaft of the float switch or the inside of the standpipe tub gets coated with soap scum or cooking oil and making it gummy. This then sticks the float down so it cannot rise to signal when the tub is full.

The solution:

Lift the float upwards, it is loose and will lift right out. Clean the inside of the cup, the rod which extends downward and the inside of the standpipe tube.Replace the cup and check the function. The cleaning should resolve your problem. If not the problem is either a defective microswitch or solenoid valve.

[Dan O.]

Dishwashers use an inverted cup float to measure the water level in the tub.

That is not correct. The float and float switch only act as a safety device, shutting off power to the water fill valve if the water level got too high. Dometsic (North American) dishwashers fill on a time basis controlled by the timer. Under normal operation, the float never comes into play. JFYI

After about 2 hours, I went to put some dishes in there and it was full of water again. The dishwasher was not even turned on.

If the dishwasher is filling even when not turned on and there is no power at the valve, the water valve is leaking. That could be caused by too little water pressure at the valve (like could possibly be caused by a partially plugged sediment screen at the water valve - if installed) or a defect in the water valve itself.

If the dishwasher's fill valve IS being powered even when the dishwasher is off, there could be a problem in the control system.

My guess is HayZee518 is probably right, the water valve is most likely defective and needs to be replaced.

You can read about how to get replacement parts for your appliances in the 'Repair Parts' section of my web site linked below.

Dan O.
www.Appliance411.com
The Appliance Information Site
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[LazyPup]

Sorry Dan O but i am correct...the float is in series with the timer....

[Dan O.]

Sorry Dan O but i am correct...the float is in series with the timer....

The float switch is in series with the water valve. When the float switch is activated, power to the water valve is discontinued. But the timer should have stopped powering the water valve before that switch is activated. If for some reason it didn't, the float would open the circuit before the water level got to the point of flooding, as a safety precaution. Here is a quote from the Whirlpool dishwasher service manual:

If the timer fails to advance past the fill position, the overfill switch monitors the water level so the dishwasher doesn't fill too full.

Under normal operation, the float switch is always closed.

Some European and Asian dishwasher models do use a float switch to monitor fill water height. But on such models they usually also have a second float to act as over-fill protection.

JFYI

Dan O.
www.Appliance411.com
The Appliance Information Site
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[LazyPup]

By necesity the timer must allow sufficient time for the water valve to fill the tub at the lowest code permitted water pressure (2.75gpm @ 8psi).

When the water pressure is significantly higher the rate of fill increases proportionally. In order to insure the tub does not overfill under these conditions the float switch is placed in series between the timer and the water solenoid thus if the float switch senses the tub is filled before the timer has completed the fill cycle the float switch opens, which in turn closes the water solenoid while the timer continues through the fill cycle and advances to the run cycle.

[Dan O.]

From a dishwasher's installation instructions:

IMPORTANT: Incoming hot water temperature should be at least 120°F (49°C). Water pressure should be between 20–120 psi.

The "flow washer" in an appliance water fill valve will regulate a constant water flow through the water valve at those pressures. So strictly a timing method can be (and is) used to accurately measure the amount of water entering the machine.

LINK > Appliance Water Fill Valve Operation Details

Under low water pressure conditions (less than 20 psi), the flow washer or the whole fill valve with a special flow washer in it can be installed to make up for the lack of water pressure to the valve.

BTW. These quote are from some service bulletins from actual dishwasher manufacturers:

"At the completion of the fill cycle the water level in the tub will be just to the bottom of the mounting clips that hold the heater into the tub. The float and the float switch on the dishwasher are for overfill protection and not to control operating water level."

"As a reminder, the water level is handled by the control board with timing. The float is a safety measure and not a water level setting."

Take my word for it, your assertion that the float is the means by which proper water level is achieved in a dishwasher is incorrect... at least in regard to modern (ie. less than 30 year old) dishwasher models.

Dan O.
www.Appliance411.com
The Appliance Information Site
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[LazyPup]

Take my word for it,,if you were to actually work on an appliance instead of maintain a library of links you would understand their function.

[Dan O.]

Oh well, I tried. You just can't teach some people.

BTW. I've been in the appliance service industry since 1976 and completed a one year college course to get my certification. I've been involved with factory authorized service for Amana, Caloric, Dacor, Danby, Frigidaire, Gibson, Hardwick, Hitachi, ISE, Inglis, Jenn-Air, Kelvinator, Leonard, Magic Chef, Modern Maid, Norge, Sanyo, Sub Zero, Tappan, Thermador, Toshiba, White-Westinghouse, Woods and York white goods. How about you?

Dan O.
www.Appliance411.com
The Appliance Information Site
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