Yesterday the dishwasher took 4 hours on a normal cycle. Usually I take no
notice of the time it takes, but lately sometimes I have sort of wondered
why it wasn't finished.
How long does the average cycle last?
Is this a fault, and if so what is likely to sort it?
That is very long and it sounds as though it may have a fault.
Modern dishwasher technology (machine and detergent) works on the
basis of filling with cold water, heating the water and then having
adequate contact time with the detergent in the water to clean the
Older technology, and that still in use in the U.S. uses a detergent
with gritty bits and a lot of water pressure from a powerful pump to
blast the soiling from the contents. It uses a lot of energy and
gradually dulls surfaces. Its only saving grace is that it is
Our machine, a Miele, has a whole range of cycles, and the length of
time depends on the temperature selected and whether a whole machine
or top only one is selected. At our most typical selection of whole
machine and 75 degrees it takes two hours to run.
I would say that at 4 hrs, something is wrong and it needs a service
call. Don't be tempted to make it fill from hot water, because a) it
will make little or no difference if the machine is a low water volume
one, b) it's not designed for this normally and c) spraying the
contents initially with hot water will set any proteins and make them
hard to remove.
The OP's dishwasher taking 4 hours does sound a long time.
Our Bosch dishwasher only takes 2 hours on the maximum setting. 80
minutes on the next setting down and about 40 minutes on the standard
It might be worth the OP checking to see that the machine is not
constantly filling and pumping out during the wash part of the cycle.
This type of fault can apparently cost a fortune if you are on a water
Dishwashers use so little water these days that, for most domestic
installations, the hot water from the instant hot water heater or from
a storage tank will never properly reach the dishwasher. By the time
the hot water travels through the pipework and reaches the unit, it
has filled up.
A cold fill only machine can also be confused by using a hot fill. It
can reduce the length of the cycle.
If the Inlet valve coil breaks down the machine may fill in sporadic
bursts as the circuit is made and broken. This may occur at any time
through the cycle so the machine will sit and wait for water before it
commences washing/rinsing and hence the time taken. At the start of the
cycle it should fill in 30 seconds to a minute and the motor should
start running. If it hasn't open the door and look. No water is a good
bet the valve is faulty as suggested by a previous post.
It seems to start ok - you know there is always a cup or knife you forgot to
put in and the water is always spraying when I open it up - cold water mind.
There just seems to be long periods when it sits doing nothing although the
water is hot when you peep in, so I don't think it is heating up. What
exactly it is doing is hard to figure as there are no noises at all during
I think you mean it is heating up.
Is the power draw releasing the powder into the wash?
Let it heat up and wait until it has pumped out and refilled with cold
water. Do you get the delays when it is on a rinse as well as when it
is on the initial hot wash?
Just to add to the general lack of specific advice :-)
Our dishwasher has a range of programmes from a 15 minute cold rinse
through to a 170 minute (i.e. nearly 3 hours) "economy" wash at 40C (or
is it 45?). The economy usually washes at least as well as the "normal"
50C or the "super" 60C wash which are 90 and 106 minutes respectively
(electronic timer, usually pretty accurate) and uses less electricity
and less water. All three have a long drying period at the end of the
I think that the economy setting works, despite the lower temperature,
by increasing the "contact time" - i.e. it just keeps washing for
longer. Is it possible that you have somehow activated such an economy
The other thing that happened to us once was that it wouldn't get out of
the initial pre-wash rinse. We discovered it wasn't filling properly
with water for some reason - and it wasn't the inlet pipework at all.
I bunged a few pints of (hot) water into the thing in the hope that if
it were a grease problem, the heat would help, and it finished the cycle
fine. I then gave it a good clean out - filters, spray bars, the lot,
and ran it on the hottest wash with nothing in except a small squeeze of
washing up liquid. It's never had that problem since, but I repeat the
empty-wash thing every couple of months, and I make sure to give it a
good clean-out every time we have something like bolognese or lasagne as
the tomato/mince combination seems to trap grease and stain certain
Someone else on this ng (one of the Andys?) reckons that a (small) drop
of washing up liquid in the machine helps keep it clear of grease as
apparently there are some sorts of grease which aren't transported well
by dishwasher tablets.
Martin Angove: http://www.tridwr.demon.co.uk /
Two free issues: http://www.livtech.co.uk/ Living With Technology
Sainsburys do some dishwasher cleaner tablets. These work very well.
The inside of the machine comes out sparkling after use.
Finish also do a dishwasher cleaner. It consists of a bottle that you
place upside down into the cutlery basket. The top of the bottle (that
is now facing down) has a type of wax seal. The seal melts when the
machine gets up to temperature and it releases the liquid into the
It's a couple of quid. The results appear to be the same as using the
cheaper tablets from Sainsburys.
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