No hot water supply to Washing Machine

Walker34

Hi,
I replaced my washing machine last year and was disappointed to find that it has no "hot water in" connection. My last machine had both hot and cold inlet connections. Now with this Zanussi model there is only a cold inlet. The problem is that I am using electricity to heat the water when I already have an indirect cylinder full of hot water nearby. Electricity costs 4 times the price of gas per kilowatt. I avoid using electricity for any heating where possible.

Seeing as I already have a hot water supply at the washing machine, is there a major problem with connecting the hot to the only inlet rather than the cold as specified in the installation manual.....if so please explain why if you know.

coylemj

The biggest issue you'll have connecting the hot water to the washing machine is that every wash will be at maximum temperature so you won't be able to wash woolens or delicates and the colours in some cottons will run because you won't have a low temperature cotton cycle.

You will be removing the machine's ability to regulate the water temperature, the only thing you'll be able to wash is white cottons.

And that's before looking at the manual which will probably tell you not to do it. It's possible that some of the inlet connectors are not designed to handle hot water so it's very possible that the machine starts to leak on the very first wash or some of the internal pipes designed to handle only cold water may perish over the course of a year and then start to leak.

Don't do it.

Merch

Thought about this myself, all new machines seem to be that way, with only cold supply.
I was thinking of hooking a thermostatic valve up to the hot supply and tee in the cold supply, if I can set it to a specific temp it will either take unheated water from the tank (still warmer than the cold supply) or cool the hot water to a desired level (whatever the machine instructions say).

If I take the cost of the thermostatic valve off, I'm still sure it would cost less than heating water up each time the machine operates, I'd have to work out the usage of the machine, maybe put an energy monitor on it (more cost) over the life of the washing machine I still think it would save, actually the longer the usage the better the saving.

coylemj

I understand that some forms of energy are more expensive than others so maybe it's cheaper to heat water with gas than with electricity but surely with a washing machine you're only heating the exact amount of water you need and it's being used immediately whereas with stored hot water there is heat loss no matter how well the tank is insulated and with a gas boiler some of the heat is blown out the exhaust.

All things considered, I can't see how there would be a significant cost difference using the water heater in a washing machine, especially if you use the low temperature cycles.

coylemj

Merch wrote: »

Thought about this myself, all new machines seem to be that way, with only cold supply.
I was thinking of hooking a thermostatic valve up to the hot supply and tee in the cold supply, if I can set it to a specific temp it will either take unheated water from the tank (still warmer than the cold supply) or cool the hot water to a desired level (whatever the machine instructions say).

That assumes that all of the water intake for a given cycle would be fed into the machine at the same temperature - surely some machines use colder water for some of the rinse cycles than the water used for the main wash?

Maybe you'd be using more energy doing it that way than if you let the machine heat the water only for the parts of the cycle that needed hot water?

I still say let the machine operate the way it was designed, feed it cold water.

Cedrus

Walker34 wrote: »

Hi,
Seeing as I already have a hot water supply at the washing machine, is there a major problem with connecting the hot to the only inlet rather than the cold as specified in the installation manual.....if so please explain why if you know.

I was at an energy seminar recently and this issue of no hot water inlet on washing machines came up, even on commercial machines. One attendee postulated that the machine manufacturers have tried to remove the risk of being sued for clothes being damaged by thermostat failure but the general consensus was that it was more likely that the cost saving of omitting a thermostatic mixing valve and a couple of temperature probes were the reason.

So dumbing down the washing machine keeps the cost down and the price looks better in the shop but you pay through the nose for the electricity over the life of the machine.

There most likely isn't any temperature probe on the inlet so the dumbed down machine will probably try to heat the water even further thus shortening the machine life. I'd follow the installation instructions.

Cedrus

coylemj wrote: »

I understand that some forms of energy are more expensive than others so maybe it's cheaper to heat water with gas than with electricity but surely with a washing machine you're only heating the exact amount of water you need and it's being used immediately whereas with stored hot water there is heat loss no matter how well the tank is insulated and with a gas boiler some of the heat is blown out the exhaust.

All things considered, I can't see how there would be a significant cost difference using the water heater in a washing machine, especially if you use the low temperature cycles.

This kind of assumes that the washing machine is the only reason to heat water, in most houses there is going to be hot water available. The savings would of course depend on the laundry load, with three loads a week in a single guys apartment you wouldn't see the difference, but a busy family could do that morning and evening every day at which point the more efficient central heating would win out.

Low temperature cycles are recommended for energy efficiency (and easier on the fabrics) but you can get mould problems without regular hot washes.

Walker34

Hi Folks,
thanks for all the great replies, which are well thought out and raise some valid points. I have a dish washer as well and wondered about the same question. Dishes,unlike clothes should be less sensitive.

I have an energy monitor and regularly I look at it and see my usage is over 4Kw which is expensive. Invariably its down to the Oven (3kw),Microwave(2Kw),Dish washer(2Kw) or Washing machine(2Kw). Anything which will reduce my astronomical bills would be welcome. At the same time I don't want to damage my appliances. Great forum b.t.w.

coylemj

Walker34 wrote: »

I have an energy monitor and regularly I look at it and see my usage is over 4Kw which is expensive. Invariably its down to the Oven (3kw),Microwave(2Kw),Dish washer(2Kw) or Washing machine(2Kw). Anything which will reduce my astronomical bills would be welcome. At the same time I don't want to damage my appliances. Great forum b.t.w.

You describe your 'usage' as 4 kW but a kilowatt is a rate of consumption, what you actually consume in a given period is measured in kilowatt hours (kWh), also known as domestic 'units' of electricity.

With the probably exception of the microwave, none of those appliances you listed will actually use electricity at a constant rate like a bulb or heater so for example, your dishwasher rated at 2 kW will not use up one unit of electricity in half an hour as would a 2kW electric heater.

coylemj

Cedrus wrote: »

I was at an energy seminar recently and this issue of no hot water inlet on washing machines came up, even on commercial machines. One attendee postulated that the machine manufacturers have tried to remove the risk of being sued for clothes being damaged by thermostat failure but the general consensus was that it was more likely that the cost saving of omitting a thermostatic mixing valve and a couple of temperature probes were the reason.

So dumbing down the washing machine keeps the cost down and the price looks better in the shop but you pay through the nose for the electricity over the life of the machine.

I'd have a different explanation: In continental Europe most domestic houses do not store hot water in large tanks like we do so washing machines sold for that market do not have hot water inlets.

The success of German makes of washing machine like Miele, Siemens and Bosch (which accept only cold water) in Britain and Ireland obviously lead other manufacturers to figure that they could save money by shipping the continental models to GB & Irl rather than make special models for us so they all dropped the hot water inlets.

You may say that its more expensive to fit a water heater but when you can manufacture the same model for the whole of Europe, the additional cost for the GB & Irl maket is offset by the manufacturing efficiency in being able to make the same model for everyone.

Cedrus

coylemj wrote: »

I'd have a different explanation: In continental Europe most domestic houses do not store hot water in large tanks like we do so washing machines sold for that market do not have hot water inlets.

The success of German makes of washing machine like Miele, Siemens and Bosch (which accept only cold water) in Britain and Ireland obviously lead other manufacturers to figure that they could save money by shipping the continental models to GB & Irl rather than make special models for us so they all dropped the hot water inlets.

You may say that its more expensive to fit a water heater but when you can manufacture the same model for the whole of Europe, the additional cost for the GB & Irl maket is offset by the manufacturing efficiency in being able to make the same model for everyone.

That's a very valid point too, although H&C inlet machines are available on the continent too, not everyone lives in the city with city water pressures that they can use combi boilers and in the south they might not even have boilers but may have solar hot water.

Even without the economies of scale, the water heater would cost less than a thermostatic mixing valve because it's a much cruder bit of kit, and of course some machines come with both. My DHW supply is never at 95 deg but that's the nominal hottest wash on my Hotpoint.

Walker34

coylemj wrote: »

You describe your 'usage' as 4 kW but a kilowatt is a rate of consumption, what you actually consume in a given period is measured in kilowatt hours (kWh), also known as domestic 'units' of electricity.

With the probably exception of the microwave, none of those appliances you listed will actually use electricity at a constant rate like a bulb or heater so for example, your dishwasher rated at 2 kW will not use up one unit of electricity in half an hour as would a 2kW electric heater.

Hi Coylemj,
I appreciate yer point, I am very familiar with SI units as a Mech-eng myself, so I understand the usage/time element but without knowing how the machines actually cycle through wash/rinse/reload and heat operations I just use a momentary measure of their usage as an indicator.

I presume that a washing machine must heat and change its water at least twice in a given wash cycle.....so total Kwh used in a single wash must be somewhere around .5 Kwh i.e. (2X.25Kwh), assuming 15mins for each heat cycle. Now factor in a family of 5 and each device running at least every other day, then the Kwh`s reallyt add up.

Merch

coylemj wrote: »

That assumes that all of the water intake for a given cycle would be fed into the machine at the same temperature - surely some machines use colder water for some of the rinse cycles than the water used for the main wash?

Maybe you'd be using more energy doing it that way than if you let the machine heat the water only for the parts of the cycle that needed hot water?

I still say let the machine operate the way it was designed, feed it cold water.

I dont know about that highlighted, but I assumed if you set a thermostatic valve for say 15 or 20 degrees it wont have that much of an impact on a wash cycle, the thing is I would say the water in the tank is probably warmer than that coming from the mains/tank in the attic (I think mine is fed from a tee from the mains).
If you have hot water you will only be using a bit of it and as its cheaper to heat by say gas than elec its a saving, if you have not got hot water then that water would be warmer than a mains supply or from the tank in the attic even.

coylemj

Merch wrote: »

I dont know about that highlighted, but I assumed if you set a thermostatic valve for say 15 or 20 degrees it wont have that much of an impact on a wash cycle, the thing is I would say the water in the tank is probably warmer than that coming from the mains/tank in the attic (I think mine is fed from a tee from the mains).
If you have hot water you will only be using a bit of it and as its cheaper to heat by say gas than elec its a saving, if you have not got hot water then that water would be warmer than a mains supply or from the tank in the attic even.

If you feed the washing machine with water that is even partially heated, you are potentially going to consume more energy overall than if you feed it cold water. I say this because whereas some rinses in the cycle will use unheated cold water, you will be feeding the machine warm water which you have paid to heat external to the washing machine, thereby offsetting some of the savings you've made by reducing the energy consumed by the water heater in the machine.

Swings and roundabouts.

coylemj

coylemj wrote: »

If you feed the washing machine with water that is even partially heated, you are potentially going to consume more energy overall than if you feed it cold water. I say this because whereas some rinses in the cycle will use unheated cold water, you will be feeding the machine warm water which you have paid to heat external to the washing machine, thereby offsetting some of the savings you've made by reducing the energy consumed by the water heater in the machine.

Swings and roundabouts.

I suppose it really depends on the source of the hot water, it may be from a solar hot water system, for example, which has minimal heating costs (ignoring capital outlay) but in most other cases I would imagine that it is more economical to have the machine heat the water as there will be no losses in the plumbing etc.

cahergowan

hi everyone , i use a whirlpool 6th sense 11kg machine . the only cycle i use is a 90 degree wash for cloths from a busy commercial kitchen . the cycle is 210 minutes long . i have a buffer tank of hot water standing close by at 70 degrees . Should i be feeding this water to my machine ? The water is produced by a wood gasifying boiler at very low cost , any advice out there
:eek:

coylemj

You're obviously not concerned about the energy equation (the cost of externally heated v. internally heated water) which means that it comes down to the physical issue of whether the machine is able to accept hot water or not. If the machine only has a cold water inlet then it's possible that the internal pipes which send the water to the internal heater are not of a specification that can handle hot water so they may perish prematurely and your warranty would be worthless.

Essentially if your machine is designed to take cold water then you can feed it hot water but it's at your own risk. Read the instruction manual and see if there is a limit to the temperature of water the machine will accept.

Edit: The instruction manual for the 6th Sense 9Kg model says: For models with hot fill: the hot water inlet temperature must not exceed 60°C. So even if your machine does have a hot inlet, the water you'd be feeding it is too hot and if you only have one inlet, you can forget it or you'll probably wreck the machine in no time.

The Red Ace

cahergowan even though you have a large capacity washer it is still basically a machine for domestic use costing little in comparison to the price of an industrial washer . the main problem with water entering at 70c is that it will swell the rubber tip internally in the solenoid valve causing it to stick open and creating a flood situation in the washroom. in older washers with two fill hoses originally they filled hot and cold together and on latter ones operated valves via a stat to gain a temp as near as possible to the one selected. to save a bit on energy consumption you could fill up your washer in the evening let it wash for a few minutes and then switch it off to let clothes soak overnight and do a 60 wash in the morning

anuprising

The Red Ace wrote: »

in older washers with two fill hoses originally they filled hot and cold together and on latter ones operated valves via a stat to gain a temp as near as possible to the one selected.

what make or model washer operated valves via a stat ?

The Red Ace

Maytag top loader or the hoover pe235 front loader

anuprising

maytag is not temperature controlled via a stat , to my knowledge no washer operates on a stat to control inlet water mixes by temp


http://www.the-appliance-clinic.com/mytgtemp.html

The Red Ace

without wanting to hog the op thread that info relates to the machines of the 70/80s etc with electro mechanical switching , they are now micro processor controlled.