Washing m/c and cold fill ... A++

It's been that way for some years now.

I have Economy 7 and the timer is always set for night time use.

But you're right, I would have thought it would be cheaper to heat the water by gas. Maybe it's something to do with many houses now having combi boilers and no hot water tank, that means it is easier for the WM to sort it out itself.

It is probably that in many locations the hot water would not have run through by the time the machine is full. This is possibly made more likely with reduced water consumption.

Chris

I agree but you do not find any with both any more. I suspect its far too complicated to monitor both and do cool washes so they cop out and start with just cold. Brian

Reputedly because the time taken to heat the water is part of the soak time the washing cycle needs.

There's also an issue with dumping very hot water into delicates and into powders/tablets, etc. designed for a low termperature wash.

Our machine does have a hot inlet but it only uses it when you select a "boil wash" (80C IIRC) all other times it draws from the cold only.

Gordon

Been like that for *ages*.

Even assuming your water is heated by gas, how much do you have to run off before HW reaches your washing machine? In many houses this could mean quite a lot of wasted hot water. Machines now only heat exactly as much water as needed. This greatly reduces wasted energy for most people. There's also the factor that modern detergents work better when started off cold and the heated to the required temperature.

Tim

On Monday 04 November 2013 13:18 Brian Gaff wrote in uk.d-i-y:

Some Meile dishwashers accept hot fill, but cold is the norm.

Also, re: washing machines, detergents work better with some types of staining if the water is cold initially - eg protein based (egg, blood etc) as hot water can cook and set the stain.

ISE makes one that has hot fill

There are a couple of drivers for this now common configuration. The first is the lower water usage, that quite often means a hot fill machine will simply end up drawing all the cold water dead leg out of the pipe and then stopping before it gets the benefit of the hot - thus wasting the hot water. The other is the increased use of low temperature bio detergents that need to have adequate contact time at a cool temperature before being heated during the cycle to be at their most effective.

Indeed. And even machines which *do* have hot and cold feeds tend to use cold, and heat it internally, for all but the hottest cycles - otherwise the incoming water may be *too* hot for delicate fabrics, etc.

absolutely ZERO

I have a pumped HW loop off my Thermal store - so never have to run a tap to get it hot.

Not relevant for me ... as previously mentioned I have pumped HW loop ... no dead leg of water anywhere.

That's very probably it. We normally usually use powder or liquid in a ball inside the machine, but on the odd occassions that we use powder or tablets in the soap drawer, we are left with sludge in the drawer, unless we run the hot tap to get hot water down to the kitchen before starting. That sludge, of course, ends up in the next rinse fill.

SteveW

You aren't typical!

So you're wasting heat & power all the time anyway? ;-)

Tim

I went out of my way to get a H&C machine, but it uses such a tiny amount of water compared to its predecessors that unless I draw off the dead leg of cold water via the hot tap beforehand, it never gets any hot from the tank. And even if I do that, it fills from mains cold and hot tank concurrently, so guess which it gets most volume of?

In short, I think that better energy/water efficient machines, combined with 30 degree detergents have made hot fill a bit redundant ...

You rarely need to wash anything above 15C these days.

By the time the cold water in the pipework is drained into the machine, very little hot water gets there anyway. In any event a cleaner wash results from starting off cold, hot water seals many stains in.

Also the machine is cheaper to make.

So H+C fill has no advantages at all.

That's fairly unusual (to say the least) in a house, isn't it?