Hot/Cold filling

[vivalalavatrice]

Let's start by the beginning...

Here the most of the washing machine are with COLD fill only, maybe the old Hotpoint (UK) were "termograduali" (as they're known in Italy), that's they had got the COLD and the HOT fill valve. Those type of machines were very common here either in the 60s but they've disappeared from the Italian market (although the same Italian producers make them for foregin market, as Merloni for example!)

There in US, every standard washer has got the HOT and COLD fill valve.

The reason of that, and what are the conseguence of this differnce I think have been very largely discussed here... thus we already know that story, but none will stop you if you want to say what do you think about )

The dishwashers instead have got ONE fill valve only...EVERYWHERE! This is because you may connect the same one to the COLD water (12-13°C, I think is the main line temp), OR to the HOT water line, as it has contemplated by the User's Manuals of the most appliances producers (here i.e. the max temp is recommended not higher thatn 60°C)

If your machine's built-in heater work well your water will be raised up to the right temperature...obviously if the entering water is already hot the work of the heater will be less (no heater work if ther's notLOL!)

My doubt is that (and it's the same of the technician who suggested me to maintain the COLD filling on the DW when I asked to him whether it were better to swap it onto the HOT one): if many type of dirt exist, and there are some type of it as "amid" (bread, potatos, pasta, corn...), which shoul be removed with the cold water BETTER... HOW DOES A DW DO A GOOD JOB STARTING WITH HOT WATER ONE?!?!?

The technician said the same speaking of the dirt onto the clothes concerning the connection of the COLD water valve ot the Washer onto the HOT one ONLY!

I suppose it's cause to the detergent, as a friend of mine said me that the same TIDE used there in US to his brother's house didn't do a good job here (Yes! He took a bos of TIDE, from there to here!)

At the end...FOR THE WASHER there will be no problem... having the HOT/COLD fill you should to do a COLD prewash, the HOT main wash, and again COLD the rinses (Warm rinses I thing should to be done on Synthetics fabric ONLY, wrinkles risks onto the other ones...I suppose).Like that for US folks who have got the doble inlet system, for the COLD fill only, you cand do it using the temp selectors and with a good internal heater job.

BUT WHAT ABOUT THE DISHWASHER! I haven't ever know about a double (HOT&COLD) fill about a DW before! So... why here we use COLD and there you use HOT...Dishes shouldn't be the same?!?!?

Any suggests?!?!?

GoodBye
Diomede

PS: I wrote an Article on my blog about that...speaking about the technical trouble of this situation...it's in Italian though... if you want me to translate for you...I'll do!

http://vivalalavatrice.blog.tiscali.it/xw2899355/

 

[toggleswitch]

I am not sure that a cold-water DW fill provides any benefit.
Then again, as a product of my zip code(postal code) and the prevailing 110v here, chances are we'd never be ABLE to use a cold water fill. So it is a moot point for us, really.

In terms of the washer, a cool pre-wash followed by a warm or hot fill seems like it would work just as well to me as a cold fill that is heated gradually (VERY gradually!) Am I wrong here?

Besides why use electricity to heat water, when a gas-fired or oil-fired central hot water heater is frequently available?

But here is the best bit of sarcasm (*SNICKER*) that I can muster up: WHAT ELSE could mannies (manufacturers) POSSIBLY do to make a cycle/programme take longer?

 

[whirlcool]

I would be very worried about a DW that would start with a cold fill cycle. The glasses would then be chilled and then to have a hot water wash come along...I think you would have glass breakage.
I think the hotter, the better for sanitizing reasons.

 

[brisnat81]

Cold fill is touted in Australia for the following reasons

Since the early 90's all DW's have had cold fill reccomended, and if you choose to use hot, then it is limited to 60degC.

It is claimed that starting out cold and gradually heating stops protein (Such as egg or cheese) getting cooked onto plates etc. As the water warms and the enzymes go to work, they gently remove the protein.

Thermal shock has never been a problem with any dw I've owned, the prewash is usually cold, or heated to warm, so when it fills for the main wash, the dishes arent much warmer than the water temp. When the main wash finishes and the fill for the first rinse occurs, the cabinet is hot Usually 65degC, the 3-4L that fills into the sump is usually heated to warm by the residual heat in the cabinet, before the recirculation of water occurs again.

The other reason for having cold, or hot and cold fills as some machines did, is that you are then only heating the water that you need to, and are not wasting hot water by having to purge the lines. EG, if a machine, goes Prewash, Wash, Rinse, Rinse, Dry, on a hot only connection, all fills are hot, when they dont necessarily need to be. If you have a hot and cold or cold only connection, then you're only heating the main wash and the final rinse which saves 50% of the energy required to run the cycle.

The Cold only connection is reccomended for the delicate or crystal cycles, as it ensures that the water in the machine is never hotter than 40degC or so. With a hot fill you cant control the inlet temp.

The Cold only fills werent really practical until the low water usage dishwashers happened, even on 240V. Most houses in Australia have Storage Tanks for hotwater which is heated off peak. When each fill in the dishwasher was around 10L, filling with cold on a full cycle would take almost 3 hours. These days a full normal cycle is about 1:45 on cold, and that gets a cold prewash, 65degC main wash, 1 cold rinse, a 65deg hot rinse and a 30 minute condesor drying period.

 

[lavamat_jon]

Well I totally believe on the cold fill principle... in most circumstances (unless your water heaster is directly next to the washer), the amount of water thats drawn in by a front loader would just the cold water that has been standing in the pipe, and by the time the fill has finished will the hot water have reached the machine. So it is more efficient in the way that it prevents any water being heated unnecessarily, plus it helps with stains such as blood that can be set by introducing hot water striaght away, without having to run a cold prewash first which will waste water and time.

In time issues, it isn't really an issue at all. The standard wash time on my Miele is 25-30 minutes, from starting the cycle to the wash drain. In that 25 minutes, it is able to heat water from quite cold this time of year to temperatures of 60*C, and also maintain that temperature for 10 minutes. So, giving that the sensing portion of the wash is about 5 minutes, on average it will only take 10-15 minutes to heat from cold to 60*C. You can extend the wash by pressing Intensive, which will then heat up in stages (0-40, maintain at 40, then proceed to higher temperatures), if one wishes. On the quickwash cycle, the wash portion is only 10 minutes yet it can quickly heat up to 40*C, and I have also used "Australian" cycles (which are quicker) that manage to do a 60*C wash with 3 rinses in 51 minutes - so cold water doesn't necessarily mean that any time is wasted.

In fact, just thinking about it, the Delicates cycle is 59 minutes if you select 60*C, and it drains for the rinses at 28 minutes. 10 minutes at the end of the wash is a stepped cooling phase (partial filling/draining of water at regular intervals), so bearing that in mind the machine can heat a drum almost half full of water, from tap cold to 60*C, and maintain the temperature after that for a few minutes, in 15 or 20 minutes. So again, cold water fill only doesn't necessarily mean more time.

In terms of dishwashers filling cold, I've had a dishwasher all my life and we've washed all glassware in it from pyrex to your average glasses to more delicate wine glasses, and have had no problems with glass breakage at all. Only time I've had glasses break in the dishwasher is when my dad, who can't load the dishwasher at all, has loaded them in the most stupid places and they have either been "wedged" in or have been stacked so that they would easily fall over, particularly in the Zanussi dishwasher we had which couldn't support glasses at all.

So all in all, cold fill isn't such a bad idea in my book and "myths" such as longer cycle times or damages to glassware is compltely untrue.

Jon

 

[toggleswitch]

Who you calling *myth* (miss) LOL ?

~So all in all, cold fill isn't such a bad idea in my book and "myths" such as longer cycle times.....

Sorry Jon, I have to disagree, on 110v (figure 1,500w heater, max.) I really believe, IMHO that there is no room for argument; A cold water-line (mains) fill WILL take longer

 

[toggleswitch]

... and the first fill in a DW WILL be cool water that has been sitting in the lines.

But I think these issues [hot vs. cold] fill are cultural /electrical system repercussions / and LEARNED ways of thinking. I'm not sure that either perspective is right or wrong.... it's just different.

Nathan:
~Even on 240V. Most houses in Australia have storage tanks for hotwater which is heated off-peak.

Little tid-bits like this that are nothing to you, are precious to those of us who just would have no way of knowing such facts. THANK YOU for the info.

 

[DADoES]

I effectively use cold water fills with my DishDrawer. Haven't had any glass breakage. 110v manages to heat to 163°F in reasonable time (but only 0.8 gals per fill). Occasionally on loads that are more soiled than usual I'll run the kitchen sink faucet until the flow gets warmed so the first fill has some heat to better deal with grease.

I think manufs that specify 120°F minimum water supply are aware that the incoming flow won't be at that temp, but it will at least be warmer/hotter than full-on cold water.

 

[maytagbear]

When I do a load of dishes,

I purge my hot water line, and every portable dishwasher manual I have seen says to do just that.

In the three apartments I had with built-in dishwashers, I purged the hot water line as well.

For me, the results make a difference when I purge the line.

Just my experience.

Lawrence/Maytagbear

 

[lavamat_jon]

Toggle,

The Miele and AEG washers I have now, can complete the heated wash cycle just as fast, & heat up in a similar amount of time that my old hot and cold fill machines (Hoover, Hotpoint, and Creda) used to take, if not quicker. The power of the heater doesn't really matter - if there is little to no difference in a 220V machine when heating from hot&cold and from cold only, then there wouldn't be a difference for 110V machines. Hot and cold fills, especially on a frontloader, are a waste of hot water IMO. It is different when it comes to toploaders however, as the greater mass of water will keep the heat in and will use enough water so as to purge the water line enough so that plenty of hot water is delivered, but cold fill frontloaders are definitely the more efficient way to go.

Jon

 

[sudsman]

Toggle

You are correct a cold or warm start is best . We can save water and time when we use it that way, for heavy soil loads that have stains the hot water sets .. we start with cold water and let i t run 2 min then heat to 140 or so for main wash. we manage to save quite a lot of time and water and supplies this way , I have found this VERY efective espeically on Surgery Work ..

 

[2-drumsallergy]

Specific heat capacity

Lets not forget the specific heat capacity of water which is around 4.187 kJ/kgK, this means to raise the temperature of one litre of water by one degree kelvin requires 4187 joules of energy.

In my house at this time of year there is an abundance of hot water because the Aga range is running, this water is stored in an insulated tank however it does loose some heat overnight when the Aga is off so I tend to do laundry at night to use this water rather than waste energy heating cold water. Thankfully my Dyson washers have hot and cold fill and yes the first 500ml of water is cold but there is still plenty of hot water enters the machine, Dyson have engineered thier machines to add cold water during fill if the temperature of the water in the tub exceeds 40ºC this prevents the setting of protein stains. I also tend to use my Whirlpool DD top loader more in the winter as it makes good use of household hot water. The argument of hot water not reaching the machine is nonsense unless you get your hot water from a very distant source. I am an appliance engineer and over the years I have never encountered a plumbing setup where the hot water does not reach the machine because it uses so little water; even the latest front loaders require around 8-10 litres of water minimum on the first fill to fully saturate the load.

Just try a simple experiment by weighing a bath towel dry then saturate it with water and weigh it again, you will soon realise just how much water it takes to saturate a load of cottons. One litre of water weighs 1000g or 1Kg.

David

 

[launderess]

Read on a UK washing machine repair site, that cold filling does make sense if one has a tankless hot water system, that is hot water is not being heated anyway. However as with the previous poster, if one has a tank hot water system the water is being heated regardless, so using that hot water does not consume that much if any energy.

When doing a warm water wash, used to let my Miele fill with cold and heat to 100F, but when Kw rates started to hit 24 cents, cut that out and fill with warm water from the taps. The washer clicks off the theromstate almost at once telling me the water is 100F.

L.

 

[toggleswitch]

So how's this for a pointless tangent?

I am with you Launderess, I do believe that cold vs. hot fill is a function of the hot water heating system type avaialble and generally found in one's area.

BTW:
regarding- One litre of water weighs 1000g or 1Kg.

A gallon of water weighs about 8.345404 pounds.
There are four quarts to a gallon.
There are four cups to a quart
Therefore there are 16 cups of water in a gallon.

So, 8.345404 pounds divided by 64 cups means water weighs 0.52159 (nearly 0.50) pounds per cup.

With 16 ounces per pound, a cup of water, then is circa half a pound, being 8 ounces. Interesting to see where fluid ounces probably comes from, eh? Cool, huh?

What I find interesting is the need to FERVENTLY believe that a cold fill is better, period. Well maybe it is in some theoretical way, but as we say here "Time is money" and "Lost time can never be found" so since a hot water fill is faster... YAY!

 

[launderess]

No Combos

Far as one knows. Miele USA rep only knew about the washer and dryer.

Miele really only brings a limied part of their laundry line across the pond. Still wonder why they will not bring over gas dryers considering it is how many American homes dry laundry.

L.

 

[launderess]

Whoops

Reply posted to wrong thread. Sorry.

L.

 

[brisnat81]

Size of Storage Tanks

Hi Steve,

I was amazed in the US at how prevelent 40Gal Hotwater tanks are. That is tiny by Australian Standards.

In Australia most Gas storage tanks are around 35 - 45 gals.
The Electric Off Peak storage tanks are 65 - 105Gals. Water heats for a maximum of 8 hours per day. Usually during offpeak periods.

That is why cold washer and dishwasher fills became prevelant over here, in that the water in the tank has to last 16 odd hours, and bleeding off for washing, or dishwashing unnecessarily means you could run out.

Its the same reason most people I know have always done cold washes. If you were to do 5 loads of laundry averaging approx 50L of hot water per load, you then run the risk of exhausting a 65Gal Tank.

My Grandparents had a bypass switch on their 1960's 80Gal Electric Tank, that let you switch it over to day rate when you ran short. When the whole family was there it practically lived on day rate, otherwise with 2 people the 8 hour a day heating period was fine.

My new Miele washer is hot and cold fill. It mixes the fill temp to 40degs and then heats from there. It isnt less efficient electricity wise as we dont have off peak hotwater and it usually shaves 5-6 minutes off the wash time. Having said that, there are now times that my machine finishes the wash to quickly.

If you're smart when you build a new house, there are actually 3 tarriffs of domestic electricity.
Peak - Available 24x7
Ecconomy - Available for a minimum of 18 hours per day, designed to be used with Washers, Dryers, Pool Pumps, Freezers, Dishwashers and costs about 1/3 less than Peak. These appliances must be hard wired.
Super Ecconomy - Avaialble for 8 hours a day, designed for water heaters and costs about 1/4 of the cost of peak.

It all boils down to what you're used to and how the variables are stacked.

In Australia clothes washing is done in cold water, but the detergents are formulated for it, as are the washers, and the cold water is rarely much colder that 20degC.

Diswashers cold fill, doing away for inlet pipe purges which waste water that our country doesnt have. With the 3-4 odd liters per fill, it doesnt take much more time to heat than boiling the electric jug.

Just some info if you're interested.

 

[toggleswitch]

I am thank you very much!

In the south of this country (nearer the hot equator) I believe hot water haters of the storage-type get smaller!

In my father's 5-2-2 apt (5 rooms, 2 bedrooms, 2 bathrooms) in Florida (WAY south) there is a 20 gallon (80L) electric hot water heater. TINY! But then again, he does not have a washer or a dishwasher! I suppose the incoming water is much hotter to start with due to a hot climate, so it is of sufficient size for those conditions.

Here in New York City, a MUCH colder climate, the "recovery" (speed of heating) and the temperature rise needed (to get the water to 120 F (50C +/-) would make an electric heater [much slower recovery than fossil-fueled one] of that size a mere toy.

Thank you so very much for the insight!
Much appreciated.

Regards,
Steve

 

[toggleswitch]

sticky *e* key

"heaters" not "haters" *BLUSH*