# Why do I need to flush out remains of previous brew?



## Beemer (Jun 19, 2012)

I have an Izzo Alex Duetto III and after each brew I blind filter backflush to get out the crud. However I sometimes have to do this up to five times before the water runs clear.

If after a brew I did not water backflush say one day the next day's brew will have crud deposits in circulation. Is this a flaw in E61 design?

How and why are grounds sucked into the grouphead?

I do chemical backflush every two weeks.

Ian


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## Spazbarista (Dec 6, 2011)

Don't back flush. Portafilter wiggle to get the grinds off the screen. Then back flush (if you must)


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## Charliej (Feb 25, 2012)

Beemer said:


> I have an Izzo Alex Duetto III and after each brew I blind filter backflush to get out the crud. However I sometimes have to do this up to five times before the water runs clear.
> 
> If after a brew I did not water backflush say one day the next day's brew will have crud deposits in circulation. Is this a flaw in E61 design?
> 
> ...


Grounds get sucked into the grouphead as a result of the action of the 3 way solenoid opening and sucking the excess water off the top of the puck and from the group and dumping it into the drip tray via the decompression pipe.


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## jeebsy (May 5, 2013)

Expobarista said:


> Don't back flush. Portafilter wiggle to get the grinds off the screen. Then back flush (if you must)


I can't quite get the hang of the wiggle. Is it explained anywhere?


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## Spazbarista (Dec 6, 2011)

Engage portafilter, start pump. Give it a few seconds for water to fill blind basket then loosen pf so that water sprays out all over your drip tray. Wiggle it so that it creates pulses of pressure flushing water around gasket.

It works. I do it after every shot if I'm going to be not brewing for a while


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## Beemer (Jun 19, 2012)

Expobarista said:


> Engage portafilter, start pump. Give it a few seconds for water to fill blind basket then loosen pf so that water sprays out all over your drip tray. Wiggle it so that it creates pulses of pressure flushing water around gasket.
> 
> It works. I do it after every shot if I'm going to be not brewing for a while


Thanks I'll be trying this later today


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## El carajillo (Mar 16, 2013)

You can help reduce the grounds/residue being drawn into the brew head by fitting a finer screen, the screens ordered by Charlie are available in 200 micron and 35 micron. These reduce the amount of contamination going back through brew head, a simple task to change them .

Do not chemical flush too frequently as this being aggressive washes out the lubricant off valves and cam ,chemical flush usually required if coffee starts to taste off due to oil residue build up in the head.


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## Beemer (Jun 19, 2012)

El carajillo said:


> You can help reduce the grounds/residue being drawn into the brew head by fitting a finer screen, the screens ordered by Charlie are available in 200 micron and 35 micron. These reduce the amount of contamination going back through brew head, a simple task to change them .
> 
> Do not chemical flush too frequently as this being aggressive washes out the lubricant off valves and cam ,chemical flush usually required if coffee starts to taste off due to oil residue build up in the head.


Thanks for the tips,

Ian


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## Beemer (Jun 19, 2012)

Beemer said:


> Thanks I'll be trying this later today


I'll pass on the wiggle technique as after trying it I'm presently nurturing a scalded finger









Ian


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## tribs (Feb 21, 2012)

After pulling a shot, run some water through the brew head to remove the brew water from the brew chamber and then wipe the filter. I usually run 2 or 3 single ounces until the water is mostly clear. I also wipe around the seals.

What you are probably seeing is dirty water from the exhaust chamber. Generally this only ever sees brew water unless you backflush with clean water or detergent. The brew valve should stop dirty water entering the thermosyphon.


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## Lighty (May 31, 2013)

I do the same tribs

quick couple of oz thru the head and a wipe after every shot and mine stays clean

my only concern was would it reduce the pump life ...


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## tribs (Feb 21, 2012)

Lighty said:


> I do the same tribs
> 
> quick couple of oz thru the head and a wipe after every shot and mine stays clean
> 
> my only concern was would it reduce the pump life ...


I'm sure it's kinder to the pump than backflushing


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## Obnic (Jan 14, 2014)

Are you slamming the lever all the way down after your shot? Better to push it half way down to stop the pump. Pause briefly then push it the rest of the way down to vent water to tray. It's a bit less disruptive to the puck this way.


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