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Can anyone explain to me why (as far as I can tell) all machines are now cold fill, we are all electric in the house and the hot water is heated at economy rate providing a constant supply of cheap hot water, so what is the point in having a cold fill only machine that heats the water at full tarriff?
Doesn’t seem either economical or eco friendly to me?Colin
no it wouldnt, and never does
the simple facts are that most peoples machines are some distance from the boiler/water tank
the machine takes the COLD water from the pipes, replacing it with hot… so the hot water doesnt even enter the machine anyway… waste of money?
u getting it now?
Re: Hot and cold fill
I take your point but if the machine attempts to take water from the hot supply at least any cold water will at least be at room temperature before it draws any hot and that is bound to be much warmer than the cold from the rising main, particularly in the winter months when outside temperature could be as low as -20 C
whichever way you look at it… the manufacturers stats prove its better
and anyway, wash performance is enhanced because it washes whilst its heating. ppl want AAA grade appliances, and thats the way they do it!
helo_75 wrote:no it wouldnt, and never does
the simple facts are that most peoples machines are some distance from the boiler/water tank
the machine takes the COLD water from the pipes, replacing it with hot… so the hot water doesnt even enter the machine anyway… waste of money?
u getting it now?
On older machines which used more water it wasn’t such a problem. On my old Hotpoint in particular the door glass would be hot at soon as the machine had filled up, dramatically cutting the heating up time. Modern machines use such little water anyway that the energy used to heat it up from cold should be much less than on an older machine.
That said my 1986 Zanussi Washcraft only takes in hot water on the 95c cycle and my 1989 Zanussi Jetsystem is cold fill only, matching many continental machines of the time.
The other point is that modern detergents work best when water is heated up gradually from cold. If you immediately introduce washing powder to hot water the enzymes are killed off.
Re: Hot and cold fill
Re: Hot and cold fill
As I wrote in that article, unless you have a true mixed fill then it is a total and utter waste of time, energy and money trying to make it work. It saves nothing basically the way that most every single front loading washing machine on the planet is set up.
That’s pretty much it really.
The only caveat is if there is a machine with a proper hot and cold mixed fill that is intelligent to a degree and, to date, there isn’t nor has there ever been, one for sale on the UK market. In fact, there isn’t one available in most of the world.
They do exist, you just can’t buy one here.
Then, if you do manage to get this mythical washing machine you have to understand that in order to make it work and use a hot supply from solar or geo-thermal especially but, any tank fed hot water supply, that there are installation requirements that have to be met to make it work and offer the savings you want on time and energy.
To make that effort worth it you have to have a machine that is ultra-durable and will last a lot of cycles otherwise, it’s pointless. You’d throw the machine away as junk before you got payback on the cost of the installation requirements.
I understand the point about ambient temperature and water held in the system being warmer than water drawn from the mains but, for most installations, in energy terms, it doesn’t make a whole heap of difference. You’re talking about the difference of a few degrees really, -20ËšC is way beyond the point at which water is frozen and generally speaking the coldest that mains will get is about 2ËšC but more often 6-10ËšC at worst. The best you can hope for internally is about 15ËšC in reality and even that’s on a really warm day with direct sunlight on the supply. I’d suspect your looking at a variance, in most cases, of about 5ËšC or so at best.
To heat 1l water 1ËšC takes approximately 0,001164 kWh which really isn’t very much in terms of actual cost. Average washer takes about 3-7l of water on wash so, multiply by the water load (which is variable dependent on load) then multiply by degree temperature rise required.
The point is, you’ll never get the same result twice using different loads, never get to the point where the energy savings are really substantial and never really be able to justify the effort. So, most washing machine manufacturers have totally dropped the notion.
Added to which you have the issue with detergents and enzymes as has been pointed out.
You also have the possibility of thermal shock on some modern mix fabrics, particularly on a lot of odd designer stuff.
In short, to fill with hot only is not really a very good idea and unless you employ a very intelligent solution it is, as I have said many times, a total waste of time and effort.
Sorry to be the bearer of bad news (again).
HTH
K.
Re: Hot and cold fill
juicehills wrote:Can anyone explain to me why (as far as I can tell) all machines are now cold fill
In addition to all the excellent technical, energy saving reasons and advice you’ve been given so far I suspect the real reason is far more basic and fundamental. In that we don’t make washing machines in the UK any more but instead import machines from Europe and beyond where they don’t have a need for hot water anyway.
Just to add another point…which is prob in Iadoms link….but any water drawn from the boiler will have been heated once….and if at a later point it goes into the washing machine , it would be heated again after cooling down sitting in the pipes. Another uneconomical action
Re: Hot and cold fill
I remember my parents used to say something like fill on 1 then wash on 4 on their hotpoint toploader. What I mean is they put it on the hottest to force the machine to take in hot only, then washed on a medium temp. If you put it on medium temp to start with it took in hot and cold together and electrically heated it a bit.
I think the same happens (or rather happened!) on the more recent machines – they err on the cold side when filling, then heat it up. The designers assume your water is an evil 80 degC and seem to allow as little of the nasty hot water in as possible!
I thought of connecting my trusty Servis M9303 Washer dryer (with hot and cold fill) to the hot only (via the cold inlet) as our water is only 40 – 50 degC, but then I realised its gonna end up doing hot rinses as well!!Tim
Re: Hot and cold fill
Modern detergents work best using cold water and heating up the exact amount you need. 😉
Re: Hot and cold fill
I just happened across this thread again when sorting things in the forums.
Have a look at this page on the ISE site
Now, apart from the fact it’s not been decided 100{e5d1b7155a01ef1f3b9c9968eaba33524ee81600d00d4be2b4d93ac2e58cec2d} whether to bring the machine is or not there are certain installation requirements, the main ones being that you have tanked hot water or a constant source (geo-thermal?) and that you have the pipework lagged to the point of dispensing. To get the benefit from using such a machine fully, the pipework has to be lagged right up to the point at which the machine connects to it otherwise you get nowhere even close to the energy and time savings as all you do is fill the machine with the cold water lying in the pipework.
HTH
K.
Re: Hot and cold fill
Hi,
I was also surprised to see that new machines are cold fill only for Siemens.
I have always preferred the hot cold fill as the gas prices were cheaper.
I understand that sometimes the hot water does not reach the machine. However if the nearby sink etc is using hot water then some hot water would get to the machine.
We have a combination boiler. So it takes a while before the hot water starts coming through.
Thanks
JM2
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