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daviddeemarin

Clothes Washer Internal Heater

daviddeemarin
10 years ago

I am installing local tankless water heat in our house. I thought I would have to install a separate heater for the washing machine but now I see that it heats its own water although the installation manual calls for both a hot and cold water inlet.

Is there any reason I cannot just hook both hot and cold inlets to the cold water?

Comments (10)

  • dadoes
    10 years ago

    Two reasons:

    1) Assuming your machine is a 120v unit sold on the U.S. market (i.e. Maytag, Whirlpool, LG, Samsung, GE, etc.) ... the water heater is not intended to heat a cold fill to anything more than moderately warm. The exception may be a designated Sanitary cycle but that cycle begins with a hot (or warm) fill as a starting point.

    2) Pretty much all washers nowadays have ATC, which is Automatic Temperature Control. ATC involves a temp sensor that monitors the incoming mixed water flow and controls the hot and cold valves to maintain an average target temperature per the cycle selection. If the machine senses that it's not getting either hot water or cold when it tries to moderate the valves, it'll probably trigger an error code.

  • dave1812
    10 years ago

    U need to hook the hot water line of the washer to your hot water system. You can't rely on the internal heater to do much heating of the water.

  • enduring
    10 years ago

    I have a question about hot water too. It takes forever to get the hot water to get to the location of machine, in my set up. And the machine doesn't use much water anyway so I think it is actually filling with cold water from the hot tap. With my Miele it seems that it is getting hot by the feel of the glass front. I have not measured the water temp though.

    I am wondering what others with a Miele can tell me about the hot tap filling the machine with cold H2O.

  • dave1812
    10 years ago

    i have an extra hose going to the hot water inlet of my washer. I installed a TEE fitting at the inlet and then ran a stainless covered hose to a shutoff valve. from the valve, I have an adapter down to 3/8" which sends water through 3/8" ID tubing, into the drain. When I run a hot wash load, I simply turn on that valve to purge the lines of cold water. It takes less than 7 or 8 seconds, if I turn it on FULL, to purge the cold water from the lines. It's easy to tell when you have run enough water through, as the valve will get hot. (I have one of those valves that you turn the handle 90 degrees from OFF to ON.) works like a champ.

  • lee676
    10 years ago

    If you want to run a washing machine attached only to a cold water feed, you can do that by buying one of the handful of 240 volt washers sold in the US, mainly from Bosch or Asko. I have a Bosch 240v washer and the owner's manual specifically states it can be attached to cold water only, although you'll need a Y-adapter for the water line to physically send cold water to both the hot and cold inlets on the washer. I don't know without looking if the Asko 240v units are designed this way; I know Miele allowed cold-only water use before they switched most of their US-market washers to 120v. All of the currently available 240v washers are the more compact 24" width rather than the more common 27", so they don't hold as much as the monster-sized washers that have become popular in recent years. They do hold as much as a typical '80s or '90s top-load washer though; the recently introduced Bosch 240v washers claim to be able to handle a 17-1/2 lb. load, which is about what old top-loaders could fit.

    The water heaters in 240v washers are typically 2000 to 2500 watts compared to 1000 watts in a 120v machine, which is inadequate for heating cold water without taking an inordinate amount of time. Even the 240v washers will have somewhat longer wash cycles when running on cold water. A side benefit is that filling with cold water will help prevent some types of stains from becoming permanent.

  • dadoes
    10 years ago

    I used a 2006 Whirlpool Duet with on-board water heater for a couple months. I had it connected to a single-tap utility faucet (with splitter). I tried several times running a cold fill on the Heavy duty cycle set at hot and the longest-available wash time to insure the heater would run long as possible. The water at end of the wash was lukewarm at best.

    The Sanitary cycle did better, reaching a strong warm or moderate hot after around 80 to 90 minutes (that's JUST for the wash period) ... but it got MUCH hotter (target temp 145ðF to 150ðF) on a hot fill.

  • enduring
    10 years ago

    Well, with my non scientific measurement, the back of my hand, I can pretty much tell that my Miele is heating my water to the prescribed temp. The hot and cold are both hooked up, and the machine is doing its thing to get the water up to temp. Right now my water is to be at 104 degrees, and through the window, it feels "warm".

  • lee676
    10 years ago

    I recall reading that the Bosch Nexxt and later Vision large front-loaders that were offered in the US for about a decade before recently being discontinued were the only 120v washers whose heaters were guatanteed to stay on until they reached the target tempereature; even if they started with cold water and a high temperature was selected (and they went as high as 175F on some models). It would take hours to reach this temperature, but it would do what the user set it for. True?

    This post was edited by lee676 on Mon, Nov 18, 13 at 4:21

  • msgenie516
    10 years ago

    I had a Maytag Epic washer with an internal heater. I read that none of the American companies produced a washer with a heater that got the water so hot that it ruined the elastic in the clothing. So I washed all of my husband's underwear on the sanitary cycle thinking it was a good thing. In the matter of a few months all of the elastic turned gray and stretched out, so I had to buy him new underwear. I never used the sanitary cycle again for anything with elastic and all is well. It did get the water so hot that I could feel the heat through the glass door.

    I know this doesn't have anything to do with the washers you are discussing, but I thought I would mention it.

    I just purchased a Maytag Maxima XL (the Epic didn't last as long as I would have liked) and am using the water with the heat setting just one step less than the hottest. However, I may have to reduce that as I think I see the elastic on his newer underwear also turning gray. And I can also feel the heat when touching the glass door.

    So, not all machines don't heat the water enough!

  • lee676
    10 years ago

    I intentionally use hot water for that very reason! The elastic bands at the top of most men's boxers or briefs is just way too tight, to the point of being uncomfortable - it makes me feel like I have a stomach ache, except I don't. It should only be tight enough to stay up, and only then are they comfortable to wear without the feeling of my waist being constantly squeezed. And they don't get that way until they've been washed and dried for about a year. The last batch of new underwear I bought was one size larger than I really needed, just so they wouldn't be so tight when they were new.