New dishwashers and hot water

[rolls_rapide]

Launderess

I'd be ecstatic to have ten minutes slashed off the wash time!

I put a moderate load of clothes into the Panasonic - certainly not jam-packed and definitely not filthy. Machine decided to wash... and wash... and wash... for precisely 1hr 45mins. Rinsing and spinning took a further 45 minutes.

Two and a half hours to wash clothes - its no wonder clothes disintegrate.

 

[rolls_rapide]

"Cold water taps are giving out water at... 100F"

Do you find that, on occasion, your cold water is full of minute air bubbles, like champagne?

 

[lakewebsterkid]

Dishwasher temperature

The owners manual for our Whirlpool does not specify the temperatures for our specific GU2300 model, but other manuals state 120*F for the normal cycle. This is fine for loads that are already washed out quite well and just need a deeper cleaning. For the loads that I wash, I always specify high temp which boosts to 140*F. I find that this is necessary for plastics to remove coffee stains from Tervis cups and Spaghetti sauce from containers. Generally, I wash my hands before starting the dishwasher to pull some hot water to the dishwasher which is about 15 feet away from the heater. However, it may not have a big benefit since these new detergents rely heavily on Enzymes. Cooler water to start would in theory give the enzymes more time in lower temps to fully work at maximum potential. If it were my choice as well, it would be heating the water to 180*F! I am sure that some of these low fill dishwashers could achieve that during their long wash time.

 

[real1]

A true three pipe hot water recirculation loop will not affect the cold water. Aftermarket units like the Grundfos work/rely on pushing small amounts of hot water into the cold side...the reason for the undersink mixing valve that hot & cold supplies plug into....at your furthest fixture from the WH.

 

When plumbing a new house, I always asked the owners if they wanted a instant hot water feature on their fixtures. So much easier at that point than relying on an aftermarket system that's not 100% perfect.  

 

Back in the day those old B&G recirculating pumps we installed were not energy efficient, not to mention every shop that installed them had to have a service tool box dedicated to them with brushes, mounts, oil and couplings. I can't even tell you how many of those pumps I serviced. All to be basically replaced by little inline pumps like Taco....which now rule the trades.

 

Kevin

 

[launderess]

Enzymes in dishwasher detergents will help with protein based soils, but have nearly nil effect on the other large component of such soils; fats/greases/oils. For that you need alkaline pH .

In commercial settings dishes are pretty much pre-rinsed or even washed before going into the machine. Very hot water and alkaline pH detergents take care of the soiling. There are enzyme based products for institutional ware washing, but these IIRC are limited to soaking products meant for flatware.

More on circulating pumps:
https://en.wikipedia.org/wiki/Circulator_pump

System in ours does not have a timer or any such feature; it runs 24/7 constantly circulating water though the boilers to hot water lines. Am guessing for certain times of day and or overnight when there is low demand, that hot water just sits in pipes heating up surrounding area.

 

[tomturbomatic]

Thank you all for the great information

My hot water pipes, except for a short run to the upstairs bath are insulated. I think it would not be too hard to follow the path of the pipe that serves the kitchen to install a return for circulation and that would put hot water a short run from the bath. I think that the amount of water I will save by not bleeding cold water to get hot will be substantial, saving on water and water heating bills.

The only thing is that a timer control would be a PITA because my weekday and weekend schedules are so different. I have my Instant Hot on a timer with two different operating periods and would probably do the same for a recirculating system. It would be great to have full temperature water for every fill of the dishwasher.

 

[DADoES]

 
Some recirculation pump system have remote controls that can be placed at strategic locations to run them on-demand.

 

[tomturbomatic]

Thank you,Glenn.

 

[mattl]

If you have any Smart devices you can easily have a smart outlet turn on and off at various times during the day and week.  Works if your scheduled is consistent.  You can pick up a Google assistant or an echo dot for $29 through the end of the year, and there are bargains out that on outlets that will work with either.

 

[mattl]

Just as an update, as I've been using the dishwasher more getting ready for the holidays I find the unit heats the water most of the time.  I run the tap to get hot water initially, but with the long cycles if I come back 30-40 minutes later the tap water is cool to warm, yet if Open the DW it's hot.  This leads me to think as suggested earlier in the thread that cycle times could be reduced if the need to heat the water was eliminated with recirculation.

 

[tomturbomatic]

Thank you, Matt. I can also plug the pump into one of my timers to turn it on and off at various times.  On weekends, it would not be that hard to run downstairs while the tea is steeping and just turn the thing on. Nothing in my house is smart, beginning with the owner.

 

[launderess]

Using digital instant read thermometer

Temperature of "cold" water coming out of tap was 101.4F. Took leaving water run for >8mins to get cold water (83F), and even longer still to reach the nice frigid water coming from outside building.

This does vary by time of day. During peak usage times (mornings through early evening) *frigid* cold water arrives almost at once after opening tap.

 

[kindalazy]

I’ve got a closed loop hot water system and is 200 foot run, with a new Grundfos Alpha pump. The old Grundfos had a remote, but inevitably I forgot to shut it off. The Alpha has the same technology as the Nest products in that it eventually figures out your usage patterns and adapts. I LOVE this product. I use the normal/hi-temp scrub, and sand rinse cycle on the dishwasher, and the pump comes really close to anticipating fill times. It took 2 weeks of “learning “but it works. Glad I have a smart home, cuz I’m not smart. I travel a fair bit and it’s nice to look inside/outside the house, control the lights, temperature etc from my tablet.