# Gaggia Classic Pro (2019) - OPV Mod



## ethanweku

Hi all, I've just recently purchased a gc pro (2019 model), and I'm trying to do the OPV mod on it, but couldn't find the location of the OPV. Does anyone know if it's adjustable, and/or its location?

Thank you!


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## RobbieTheTruth

I watched a video on the official Gaggia Youtube page and I think they said they have removed that option on the 2019 machine.

About the 6.40 mark on this video. I don't know if he means it, or is just trying to discourage it!


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## El carajillo

On the video he does say you cannot adjust on this model.


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## ethanweku

I watched the video and you guys are right.. that's very disappointing!.. Im planning to install a pid on this machine, do you guys know if this model supports a pid?

And also another question, can you control the pressure via a pid mod? Or is there an external mod for the pressure?


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## El carajillo

Simplistic answer = NO and NO


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## ashcroc

ethanweku said:


> I watched the video and you guys are right.. that's very disappointing!.. Im planning to install a pid on this machine, do you guys know if this model supports a pid?
> 
> And also another question, can you control the pressure via a pid mod? Or is there an external mod for the pressure?


You can get a PID kit for these from@MrShades. He hasn't managed to work out how to override the auto shutoff yet.

If the guy in the vid is correct & the OPV isn't adjustable, you could always look at fitting a dimmer which would also give you the ability to pressure profile. You'd also want to fit a manometer & may need to replace the pump for an inversys one too. Unfortunately, this model is Lc27jg52qquxen for anyone to have tried it yet (as it would void the warranty) so there aren't any footsteps to follow.


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## MrShades

You could fit an extra OPV from the earlier Classic - as the boiler/group is the same.

You'd leave the existing one on the pump and fit an additional adjustable one (Gaggia part 11012627 - about £35) in the usual location - and just T a piece of tubing from it into the tank return pipe (from the factory OPV).

You'd then have two OPVs - one at 15bar on the pump and another (adjustable, set to 9 bar) on the group - and this one would obviously render the factory one redundant.

Not cheap, but I don't see an easier way.


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## Bausy

I shortened the spring on the pump relief valve. 1000kpa down from 1500kpa. I took about 2-3mm off the length of the spring. Works well and pressure is consistent.


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## coffeeuser1

In case above link doesn't work: https://yirga.pl/adjustable-opv-gaggia-classic


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## Rhys

nunu1 said:


> In case above link doesn't work: https://yirga.pl/adjustable-opv-gaggia-classic


 Nice little write-up for adjusting newer Classics. Although I'd disagree with you about 6 Barr as it's suitable for light roast, and crema isn't everything. The taste should come first, how it looks is unimportant.


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## MrShades

Well, I can find this: https://yirga.pl/adjustable-opv-gaggia-classic

BUT I don't see how that is doing ANYTHING - as the OPV is inline with the main water delivery pipe. An (adjustable) OPV has a screw/spring mechanism that allows water to flow past when it's above a set pressure. The way this OPV has been installed, the pressure will just build to his set pressure (say 9 bar) and then flow 'past' into the delivery tube, and then it'll continue to build (to say 15bar) and the OPV will just continue to deliver it at 15 bar. Seems bonkers and useless.

What he should have done (IMHO) is install a T-piece in the water delivery tube, and then mount this OPV on the T - with the output of the OPV going back to the tank. Doing it this way means that the pressure will build in the delivery tube until it hits the required pressure (say 9 bar), and then excess pressure will be dumped back to the tank, keeping the delivery tube at 9 bar.


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## Tom_

MrShades said:


> Well, I can find this: https://yirga.pl/adjustable-opv-gaggia-classic
> 
> BUT I don't see how that is doing ANYTHING - as the OPV is inline with the main water delivery pipe. An (adjustable) OPV has a screw/spring mechanism that allows water to flow past when it's above a set pressure. The way this OPV has been installed, the pressure will just build to his set pressure (say 9 bar) and then flow 'past' into the delivery tube, and then it'll continue to build (to say 15bar) and the OPV will just continue to deliver it at 15 bar. Seems bonkers and useless.
> 
> What he should have done (IMHO) is install a T-piece in the water delivery tube, and then mount this OPV on the T - with the output of the OPV going back to the tank. Doing it this way means that the pressure will build in the delivery tube until it hits the required pressure (say 9 bar), and then excess pressure will be dumped back to the tank, keeping the delivery tube at 9 bar.


 I still have this OPV from my previous machine. My new Gaggia Classic pro will arrive shortly, so I can't just yet explore the thing myself. But is this what you meant? Is this in anyway useable, you think? The flow of 15 bar in to 9 bar out is a male and female 3/8" thread.

If it's not useable, I'm quite interested in your mod. Nice website you made for it, btw!


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