# Gaggia classic outlet problem



## RS Designer (Dec 7, 2015)

I have a year old Gaggia Classic, only pulls 6 - 12 shots a week. Until recently after pulling a shot I would switch off the pump and hear the outlet pipe expel into the drip tray, this no longer happens unless there isn't any coffee in the filter, so no pressure the overflow works, with pressure nothing.

What I have done so far: removed the SOLENOID VALVE and VALVE ASSY (OPV), they both looked like new, no dirt no blockages. Adjusted the OPV (270 turn). Removed the shower plate and shower holding plate, cleaned replaced.

I can use the machine but I just know it's not working like it should, anyone got any ideas?


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## Jumbo Ratty (Jan 12, 2015)

have you got a blank basket ?

are you saying with that in situation it wont backflush?


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## RS Designer (Dec 7, 2015)

I haven't got a blanket basket so I cut a plastic disc to fit inside the actual basket, I could hear the pressure build a little but there was no outlet when I switched off the pump.


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## RS Designer (Dec 7, 2015)

hear!


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## Jumbo Ratty (Jan 12, 2015)

there is an edit facility,, also there are like and thanks buttons









Have you used a special backflushing powder like urnex cafiza on a regular basis ?

If not, id still guess its the solenoid valve.

but maybe adjusting the OPV without a pressure gauge could be the cause


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## yardbent (Aug 8, 2015)

RS Designer said:


> ............... Adjusted the OPV (270 turn). ...


what is it now ---10 bar..?

guess or used a gauge..?


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## RS Designer (Dec 7, 2015)

A guess I'm afraid, I do not have a gauge, my hope was a 270 turn on the valve would give me something close to 9/10 bar and would be better than the 12 bar factory setting. I adjusted the OPV after the problem started to see if it would point to the problem. I live in a very soft water area, we never get any lime scale in the kettle, would a back flush with urnex still be necessary/advisable?


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## Jumbo Ratty (Jan 12, 2015)

RS Designer said:


> I live in a very soft water area, we never get any lime scale in the kettle, would a back flush with urnex still be necessary/advisable?


Yes.

It removes the residual build up of coffee oils and particles that can partially block the machine and should be done regularly.

I do mine about every 10 days


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## RS Designer (Dec 7, 2015)

Advice taken, potions and blind basket ordered. I think I might wrap them up for my wife for Christmas, she'll love them!


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## yardbent (Aug 8, 2015)

RS Designer said:


> A guess I'm afraid, I do not have a gauge, .................


I built one for less than £10

.

  

.

http://www.ebay.co.uk/itm/141174903175?_trksid=p2057872.m2749.l2649&var=440245944374&ssPageName=STRK%3AMEBIDX%3AIT

.

http://www.ebay.co.uk/itm/110726500653?_trksid=p2057872.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT


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## Jumbo Ratty (Jan 12, 2015)

She will be thrilled.

heres a good video showing exactly how and why you should be doing it


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## RS Designer (Dec 7, 2015)

OK, blank filter and cafiza received. I have twice back flushed without any improvement. How caustic is cafiza, would it be unwise to let the machine sit with it in the pipes for an hour'ish in an attempt to dissolve stubborn oils before flushing out with water?


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## hotmetal (Oct 31, 2013)

AFAIK it's only food-grade detergent (not salt as Chris wonders in the video) and I wouldn't think it would do any harm to leave it to soak for a bit. If you leave the shower screen in place it might cause discolouration to the aluminium dispersion block but no real harm I think. The thing is, if there's no flow through the valve it's going to take longer to do its work so yeah I'd try leaving it for a while. My only other thought is whether an electrical connection to the solenoid has failed, preventing or from switching to 'exhaust'. But you say it does vent down the pipe in low pressure use so I could be wrong. I never took mine apart.

Oh yeah I meant to add: in the "pass it forward" section there are at least 2 basket manometers doing the rounds. You can join the queue and at some point you'll get sent one. You then set your OPV accurately and send it on to the next person on the list.

Good forum this!


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## hotmetal (Oct 31, 2013)

13 valves


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