Dishwasher Rinse Agents

[doityrselfguy]

Mechanically, how do dishwashers dispense liquid rinse agents, like Jet Dry, into the machines? I wash one full load a week, and one bottle of Jet-Dry seems to last forever. I have a middle of the line 2-year old GE. I envision a very simple tube running from the dispenser to the base of the door, with a slow internal drip. I can't imagine this function is complicated. Does anyone know?

Thanks,
Pete

 

[brisnat81]

Rinse Aid

Hi Pete,

On the Dishwashers we have in AU, there is a tank in the door, that holds the rinse aid.

When you lower the door to load, a preset amount of rinse aid runs out of the top of the holding tank into a much smaller tank above it.

Then when the water reaches the correct temperature in the final rinse a solenoid activates opening a small hole in the small tank, and the rinse aid runs out a small hole near the detergent dispenser.

I drew a picture to try and explain better. The red line indicates the path the rinse aid takes to get into the smaller tank.

 

[doityrselfguy]

Ask and ye shall receive...that makes sense. Looking at my GE, I think the small discharge hole you refer to is located somewhere near the base of the inside of the door, because it isn't visible anywhere else. Thanks brisnat81!

Pete

 

[appnut]

Pete, on U.S. machines the amount is released by a solenoid during the final rinse, all controlled by the timer, not anything to do with temp inside the machine.

 

[brisnat81]

Dispensing Time

Hi Appnut,

What I meant was that the timer activates the solenoid to dispense the fluid once the temperature inside the dishwasher is correct.

Nathan

 

[appnut]

No Nathan, there is no temp-related activation of the dispenser in an U.S. produced machine as far as I know. It's only time-related, both mechanical and electronic timers. Bob

 

[brisnat81]

Gravity Measurement

Hi Bob,

Does the solenoid work in the manner I've suggested, or does it control the amount of rinse aid dispensed?

I guess what I mean is, does the rise and fall of liquid measure the rinse aid or is the measurement done electromechanically?

Nathan

 

[kenmore1978]

rinse aid dispensing

Not all machines used a solenoid. The later D& M built machines used a bi-metallic strip that opened a plunger to release the rinse aid. detergent cup also was released this way. And they were in series with the heater, so if heater was bad dispensers wouldn't work.

 

[tolivac]

Dishwasher Detergent tray door release

In my vintage KA18 dishwasher-there was an arcing and sparking one time when I started it-came from behind the door panel.-opened it and found one of the detergent tray opener devices burned.The other was getting the front of the machine hot-Are these Bimetal devices?I ask because of seeing Kenmore1978 entry on Bimetal valve openers for rinse aids.(in my machine its a soleniod)I am going to check the appliance parts place here to see if they have any replacements.