washing machines Noisy pumps even on Brand new washing machines

[andyr12345]

I wonder why in this day and age manufacturers are still using noisy pumps on their washing machines (especially noisy/growl'y at the end when there is no more water to pump out) - I have a 10 year old Dishwasher that pumps out the water into the drain lovely and quiet and smoothly. 

I understand that dishwashers have a different type of pump (a recirculating pump) but why could they not fit the same kind of pump to washing machines too? or even at least on high end / mid range washing machines at least (have the likes of Miele etc got quieter pumps?) - would there really be a huge difference in manufacturing costs of fitting a dishwasher type pump to a washing machine? 

You are in a scenario of having a nice quiet brushless induction motor .. and then you have this noisy growly vibrating pump noise as its pumping out the water. 

what does make a dishwasher recirculating pump a lot quieter than a Washing machine pump? - is it the impeller?  - both pumps are brushless are nt they?

[Whitegoodshelp (Andy)]

Hello Andy. I agree, washing machine pumps are ridiculously noisy. They didn't used to be anywhere near as noisy. When I first started repairing them a washing machine pump was a small induction motor with a fairly large impeller. It had roughly a dozen separate parts, and every single one of them right down to the smallest little clip was available as a spare part. If they leaked I would strip them completely down, get a wire brush out and clean and buff them up inside. Then I would replace both the seals. I remember one was a small round seal in the centre protecting the bearings called the Angus seal. The bearings on each side of the rotor had small brass parts inside and the pump was very quiet indeed. They were always repairable no matter what went wrong with them. But then of course came the years where fierce competition in the market forced everyone into the tragic spiral of cost-cutting that has left us with relatively very poor quality appliances.

The pumps they have used for decades now are very cheap. They are also of course totally unrepairable. Sadly even Miele washing machine pumps are relatively noisy. It's perfectly possible to make a nice quiet pump - but at greater cost. Presumably people never complain about it. So nothing changes. They can make a very annoying noise, especially as you say when pumping air. Presumably people just accept that that's the noise a washing machine makes.

 

 

 

 

[andyr12345]

yep, - do you know how these so called 'Self-cleaning' pumps work? . I am supposed to have one on my Hotpoint WMUD843P . but I still have had to take the 'filter' out though from time to time and empty out stuff like coins, plastic, buttons etc. And how do they self clean themselves then?, and could this also be the reason why they are noisier that the old type pumps? 

I wonder what the chances of an old type Hotpoint pump fitting my machine. I know the grey outlet pipe would fit , but I wonder if the diameter of the big black sump hose would? ... or even if I got a sump hose with the old type pump , would that fit to the outer housing/tub of the drum? - would both pumps be 240v because these newer pumps have very thin solid wires with a mini plug on them - whereas the old type hotpoints had thicker brown and blue wires with large spade terminals. If there is too much involved i wouldnt go down that road . But I am just curious at this moment in time. 

Also you know the ping pong balls (oko ball its called isnt it) whats your view on them? - I remember years ago washing machine engineers used to take them out and leave them out saying they caused more trouble than they were worth and that they used to make the pump noisier or something? - have you ever heard of that? - did you used to take them out when you were repairing Hotpoint washing machines? - Its supposed to be there so it fills up with sump with water isnt it so to save washing powder or is it to cover element with water so it can start heating water in the sump quicker?

[Whitegoodshelp (Andy)]

I think self cleaning is a misleading name for them Andy. They don't clean themselves, they just are supposed to not jam so easily if something gets stuck in the impeller (which it shouldn't anyway because of the pump filter). The old induction pumps ran in one direction and if something got stuck inside it would jam up. The cheaper type are supposed to reverse direction if they jam to try and free up the obstruction. If something gets stuck inside the pump it can make a right racket as it gets tossed around inside.

I think the new pumps are still 230 v but not 100% sure. They take so little power to run they probably don;t need thick wires. The timer motors on the old Hoover timers have extremely thin wires but were mains voltage.

The balls can get sticky from gunge and stick inside the sump hose causing not pumping water away faults. The old Hoover New Wave and Soft Wave washing machines were bad for that. However, it would depend on the design of the sump and fitting for the ball as to whether one could suffer from that problem or not. I sometimes took them out if they were in a very gungy dirty machine. They are supposed to prevent detergent wastage but washing machines didn't have them for many decades and we didn't have any problems.

[andyr12345]

Thanks for the info and reply Andy. - just another observation, if you dont mind. On my older hotpoints the drain pump ran all the time when spinning (and in pump out/emptying) but these new hotpoints (well in the last 5 years or so) the pumps go on and off through the spin or pump out cycles - it only seems to pump out when it detects water in the sump and I reckon when the sump is empty the pump motor stops. Do you reckon they have designed these to run like this these days to either stop the pump from burning out/prolong life of pump? , save power? or  stop the pump unnecessarily pumping air a combination of all three, or just some other reason? - also where would they get a 'signal' from to start and stop pumping ? - I am predicting from the linear digital water level / pressure switch at top right of the machine? - or is there some other sensor I have missed? - or does the pump itself have a sensor in it that detects water and cuts out when there is no water in the pump area? - just curious Thanks.

[Whitegoodshelp (Andy)]

Hi Andy. I can't imagine Hotpoint going to the trouble and expense of any of those possibilities. There's no advantage I can think of to switching the pump on and off during spin. At a stretch I could imagine it might help pump a little more water out at the end if they let it build up a little. Pumps can't pump little dregs up. But that wouldn't help get more water out of laundry, the water left unable to be pumped out at the end of spin is only a mug or 2 and inside the sump hose. It always has been and it's not a "problem" any manufacturer would be likely to consider trying to fix because there's zero impact to customers or laundry.  I can't imagine them fitting sensors, nor caring even slightly about the longevity of the pump. If they are turning off the pump I would expect they would just do it using timed intervals. Anything more sophisticated would be unnecessary and I'd be gobsmacked if a manufacturer like Hotpoint would have gone hi-tech on something as pointless as switching the pump on and off

[andyr12345]

Thanks, yes its a strange one this one. I couldnt imagine it being on some kind of timed interval solution. Somewhere it is getting detected that there is no more water to be pumped out, so I reckon it must be getting a signal from the electronic linear water level switch at the top of the machine then - if its not for saving wear and tear on the pump solution it must be to cut down on noise , as the machine already has a silent washing machine motor (silent wash) maybe they thought it would make sense not to have pump working away when there is nothing to pump away (plus making the pump more noisier than usual when not pumping any water out .. ie when its pumping air)  - maybe on the cheaper hotpoints without Brushless Induction wash motors maybe they are on constantly throughout the spin cycle or drain cycle ?

[Whitegoodshelp (Andy)]

Hello Andy. I'd still be amazed if they use a more complicated and expensive way of turning the pump on and off. I'm not saying they don't, just that I'd be amazed They know how long it takes to drain the bulk of the water, (probably about 30 seconds or so - roughly). So once the bulk of the water has gone they can just switch the pump off for x seconds then switch it back on and so on. There would be no need to need to know water levels. No more water is being introduced so it's just small amounts running into the pump which they can easily let build up. If it goes into a short spin they know it will create a small surge of water but that will be pumped away in 10 seconds or so and be back to a small trickle. Doing it that way would cost absolutely nothing, just an adjustment in the wash cycle software. 

[Whitegoodshelp (Andy)]

On 11/06/2017 at 00:31, andyr12345 said:

Thanks for the info and reply Andy. - just another observation, if you dont mind. On my older hotpoints the drain pump ran all the time when spinning (and in pump out/emptying) but these new hotpoints (well in the last 5 years or so) the pumps go on and off through the spin or pump out cycles - it only seems to pump out when it detects water in the sump and I reckon when the sump is empty the pump motor stops.

Hello Andy. I just came across this old topic. I'd just like to say that yes you were correct. Many of the Hotpoint washing machines do turn the pump off once they have detected that the water has gone. Historically this has never happened before and I still don't really see the sense of it. It just makes it difficult to test the pump if it only runs when water is inside. The last thing you want to do when investigating a faulty pump is to put water in the drum that might not get pumped out. I suppose an argument is that it saves wear and tear on the pump but I'm struggling to think why the manufacturer would be bothered about that when they make so much money selling replacement pumps. :-)

[andyr12345]

12 hours ago, Whitegoodshelp (Andy) said:

Hello Andy. I just came across this old topic. I'd just like to say that yes you were correct. Many of the Hotpoint washing machines do turn the pump off once they have detected that the water has gone. Historically this has never happened before and I still don't really see the sense of it. It just makes it difficult to test the pump if it only runs when water is inside. The last thing you want to do when investigating a faulty pump is to put water in the drum that might not get pumped out. I suppose an argument is that it saves wear and tear on the pump but I'm struggling to think why the manufacturer would be bothered about that when they make so much money selling replacement pumps. :-)

indeed - and it cannot surely be for eco / saving electricity by turning the pump motor off ? - what does a drain pump consume?, maybe 25w at most if anywhere near that?  

I personally think they should have left it the old original way with the pump on throughout the spin , because with centrifugal spin anyway its going the 'squeeze' all that water out anyway and it has to drain off at some time anyway so why not keep it on constantly with it spinning away anyway - i dont personally like the way it stops and start and waits until a fair amount has built up in the sump before engaging  and pumping out the water.

[Nicnac]

Hi Andy, very old topic I know but did you ever source a quiet pump for your hotpoint?

I only ask because I baffled as to why any manufacturer would go to the expense of fitting a lovely quite brushless motor and leave the pump component as was. 

It would be nice to track one down and fit without to much bother, my machine is so quiet up to the point when it sends any current to the pump then it's eardefender time. 

[Whitegoodshelp (Andy)]

I agree, a brushless motor just makes the pump sound even noisier. Some washing machines pumps are ridiculously noisy. It's totally unnecessary apart from the fact that they often want to just fit the cheapest parts possible. Throughout my time in the trade I have seen many washing machine pumps that are very quiet. 

[andyr12345]

yep, its not even the actual pump motor itself is it? , because that's brushless too and if you took that off and wired it up it would be as quiet as anything without any water running through it. - its seems to be the combination of propeller in the pump and air in the water its emptying out  that makes it sound noisy when emptying and when they are empty of water, they just start growling then . sure they can make them quieter or they should just use the pumps they used to put on the old hotpoints think they were much quieter by memory

[Peter H]

Well things have not changed - just got a brand new Miele WTD163 washer dryer - absolute rubbish. Pump keeps going at the end of its cycle - sounds like a steam train - functions poor with little control over drying - no cooling mode - horrible beeping noise on control wheel - leaves clothes creased, will not do a 1600 rpm in express mode - I could go on. Anyone finding this - avoid buying it - BUT it sounds like many other makes are the same - they even use similar control/program functions and pictures in manual - what a world we live in. Wish I had my old WT2780 repaired now!🤬