Solar Heated Water for Washing Machines with a Cold Feed only.

[Paulh_Boats]

I can feel a Dyson moment approaching........ 

[northern installer]

what,you mean you are made of lots of bits of plastic,and they are about to fall off and be lost under the sofa

[Phil]

Ivan/List,
 Can I go down a different route,How about a washing machine with only 1 input No sensors (sensors always seem to fail and are expensive to replace) You could have a heating element but with that rare thing an ON/OFF switch and manual thermostat this gives the operator full control over the washing temp by use of a dedicated conveniently situated mixing valve.  Basic washing programs that tell you what temp is needed and if that temp isn't forth coming will wash it anyway.
High quality bearings and seals, low wattage motor.   Well constructed casing giving easy access to the inside  and a good supply of spare parts. and what about a top loader with less stress on the bearings (but not sure on the energy useage between the two)
 For me washing machine heaven  
 

[Paulh_Boats]

Ivan,

How about a bolt on device with hot and cold solenoids, mixer set to 30C and a drain solenoid that feeds the water recovery system/water butt.

Drains hot for 30 seconds then tells user to start machine that fills efficiently at 30C.
Then after 5 minutes the device closes the hot and opens the cold valve, so that rinses are done with cold water.

Should work with existing cold fill machines, as long as they don't complain about 30C incoming water.

Could be bodged together with bits from an old machine and a microprocessor. Ivan, you really must persuade me to blow the dust off the eco-controller design 

 

[djh]

My thoughts are thus (for solar-ready washing machine):

I like this idea, and I also like Phil's KISS idea too.

3. Prior to filling, the washing machine drains hot water to waste until hot water at washing machine is within 5C of hot water measured at wireless sensor, unless say 120seconds has passed, in which case, the bypass-to-waste is aborted (avoids draining unnecessarily large volumes of water in the event of a failure)

If the hot water is hotter than it needs (which I guess it normally will be), it doesn't need to drain to waste, it can just start to fill with what's in the pipe and cut down on how much cold it adds later.

As regards getting hold of these, it might be worth noting that in Singapore and presumably other hot places they've always washed with 'cold' water anyway. It's always over 30 there. So machines designed for such places are cold fill only and won't object to being filled with warm water. The ones I've seen are top loaders.

Cheers, Dave

[Mickey]

I could not have imagined that my simple initial thread would have generated such lot of inspired responses.   

Ivan is right we need a proper designed washing machine that will accept solar preheated water - at whatever input temperature.  It's sensors and software will have to decided to heat or cool the supply flow,depending on the type of wash required.  Not much to ask for?

I'm off on holiday for a few weeks but will be checking the forum from internet cafes or on my laptop if I can find a WiFi hotspot in the Australian outback.

Mickey

[Ivan]

Some great ideas there. I especially like the idea of incorporating a mixer valve. I reckon the machine should fill with warmer water than needed, due to the heat loss to the drum etc (as mentioned earlier in this thread). With a bit of experimentation in development, it should be able to fairly reliably predict the temperature drop, and compensate for it. We'd still need a cold option, as well as the hot/mixed connection, as we don't want to use hot water for the rinses.

Paul, are you serious? Would you contemplate this as a serious project? I reckon I could get some R&D money, if we could be sure of seeing the project through. I think the idea of taking the simplest machine on the market and replacing the controller, plus a few other bits and pieces might be a great way to do it.

Mickey, I think the thread has generated a lot of interest, because you've hit upon something that's been niggling in the back of a lot of minds (mine for sure)


Ivan

[heatherw]

My washing machine is cold fill, and puts up with water temps of 25 to 30ºC in the summer.  when I used to develop films I had to change the developing times in summer, because the water was over 25ºC, that's how I know.  (Wouldn't normally take a thermometer to the washing machine water.)

I don't think it's a special kind, just a normal LG, no tropical setting like you get on fridges here.

[Paulh_Boats]

Ivan, list,

I think retro-fitting a machine is a bit ambitious - better to start with something simple outside the machine then existing machines could benifit and the concept could be tested.

A device that drained the cold water in the hot pipe at the push of a button and automatically stopped when it got to 30C or 40C would be simple to use. All it needs is an optional mixer, a solenoid valve to drain the pipe, a push button and a green LED to tell you the water is warm enough to start the machine. If the water cools the LED goes out and you press the button again etc.



The second phase would be for the device to wait for 5 minutes for the filling to finish, which would be well before the rinse cycle has started. The device could shut its hot valve and open its cold valve so that now only cold water could flow into the cold feed for rinsing. After 3 hours the device switches off all valves automatically which should be long enough for any cycle to have finished


However if manufacturers simply fitted a hot feed that was intended to be plumbed to a 30C mixer this second step is not required, and the machine could simply pump off the cold water until the water warmed up to 30C. It seems simple to me and could be developed by any manufacturer right now with just a change to their software...have I missed something?

[wookey]

Paul. I think our machine can take longer than 3 hours sometimes (mostly because it can stop and have 'soak' stages. Not sure if it is supposed to do this - it's a bit cranky.

LIke lots of others here I've been thinking about all this too. Previous machine was a hotpoint with hot+cold fill which lasted over 20 yrs (we only had it for about 12). Must have been one of the first with 'computer control' - and a  lot of red LEDs :-) That appeared to do a proper hot+cold proportional fill, although I never measured it. New one (whirlpool AWM328) has hot and cold but mostly only seems to take cold, presumably it's one of the 'take hot for 60C washes' variety. It also leaks a lot and is generally tiresome. We'd be customers for a solar-adapted machine.

I could help with pic-controller hacking if we tried that. The problem with modifying an existing model is model churn. You will probably only be able to get a particular flavour for a year or so before having to re-do the excercise.

We're intending to plumbboth dishwasher (Bosch Classixx) and W/M onto hot water input once the solar is working. I'll put some moitoring in to see how it works here.

Funny how enormous effort has gone into reducing water use in machines, but almost none into reduced hot water energy use (I suppose less water needs less energy to heat up, so there has been some). This is odd as energy use is a much bigger problem than water use (in the UK at least).

[Bob]

Maybe someone has already suggested this but the really simple solution is to use one of the Whirlpool/Maytag/GEC top loaders that will accept whatever water you throw at them.

There's one in my kitchen and providing I don't let my daughter know her white school shirts have been through it there's never a problem.

Another big advantage is that they have a bigger capacity than your normal front loader.

[room101]

We have a Indesit WIXXL 146 cold fill only but it has temp control knob on front (range from no heat to 90) I tend to set it on no heat and just use a bit of vanish on the worst bits coupled with some eco balls, have been using them for a year now and the results are fine....

[Capcave]

I have a maytag top loader without any heater in it which is great for using the solar as long as you give the tank time to heat up in the morning before you put the washing on. It's built like a tank and seems to work well and uses a lot less energy than the front loader it replaced.

[renewablejohn]

Mickey

washer is an indesit 1300 . We also had problems with water pressure with this model. cold water tank was only 6 mtrs above washer. Have now included washer on pressurized water loop  to solve the problem using a shower pump.

[jude]

I bought a reconditioned hot and cold fill washer on Fleabay. Works a treat.

I'd quite like one of these http://www.comet.co.uk/cometbrowse/product.do?sku=389447