# Stuck with new Gaggia Classic 2015 - tips on pressure!



## tdfg7583 (Nov 16, 2016)

Hello.

First post and new to taking coffee seriously. I've just been bought a new (2015) Gaggia Classic. It was a gift and I can't really change it, although I know a used older model may have been better. Now I can live with the lack of the 3-way solenoid valve, and the steel tank is probably no bad thing, but I only just realised that there is no adjustable OPV valve. Bugger!

I assume they will ship with higher pressures for the ESE pods. Has anyone tested a new Classic to see the default pressure at the group head? If it is too high, will this totally ruin my attempts to make proper espresso without the pressurised basket?

If I have 10-11 bar at the group head (instead of the 9 I'd want), is there anything I can do to the tamp or the grind of the coffee to compensate and improve the shot? Can this machine still make a decent (if not great) espresso, or am I totally stuck with a dud?

Thanks.


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## Jumbo Ratty (Jan 12, 2015)

tdfg7583 said:


> but I only just realised that there is no adjustable OPV valve. Bugger!


as far as i know anyone thats put a pressure gauge on the 2015 classic has found it to be at 10 bar factory set.

There actually is a way of adjusting the opv valve on them.


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## Jumbo Ratty (Jan 12, 2015)

a good thread to read if you have a 2015 classic

post #134 for the OPV pressure as i mentioned above,, but there is also described in the thread somewhere how to alter the OPV valve if you wish

http://coffeeforums.co.uk/showthread.php?21593-Poss-mod-no-goes-on-the-2015-Classic/page14


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## tdfg7583 (Nov 16, 2016)

Thanks, that's actually a huge relief!

I'm not 100% sure from the thread what tool might be needed to make that valve adjustment, but I can research some more if necessary. I guess my next step will be to get a pressure-gauge to fit the portafilter and see what my new Classic is putting out.

If it is around 10-bar, is that close enough to ideal, or worth adjusting to 9-bar, do you think? Are there any adjustments to the grind or tamping that could be useful for now if my pressure is above the ideal range?

I'll report back when I get my hands on a suitable pressure-gauge, anyway


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## Jumbo Ratty (Jan 12, 2015)

tdfg7583 said:


> If it is around 10-bar, is that close enough to ideal, or worth adjusting to 9-bar, do you think?


IIRC a reading at 10bar at the pressure gauge means 9 bar pressure in actual use



tdfg7583 said:


> Are there any adjustments to the grind or tamping that could be useful for now if my pressure is above the ideal range?


Id just ask if you're using the pressurised filter basket that came with the machine or have you since got a un pressurised basket?

If you havent got an un pressurised filter basket then thats the first and easiest upgrade to make with tremendous results compared to the stock one.


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## jimbojohn55 (Jan 15, 2016)

I would debate if the older model is better - I'm going to do a side by side test (espresso and steam off) soon of the pre and post 2015 models as I have both like jumbo - get a vst 15g - will make a big difference and a descent grinder - my 2015 was 10bar without mods. and don't feel stuck - based on the results I'm getting taste wise from both machines their identical - and the 2015 has an SS boiler (bigger) so possible long term durability -


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## Jumbo Ratty (Jan 12, 2015)

didnt think VST did a 14g

If you do get a VST get ridgeless,, ive got the 15g VST ridgeless couldnt be happier


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## tdfg7583 (Nov 16, 2016)

Excellent, thanks!

I was off to pick up a non-pressurised basket this afternoon; there's a Gaggia shop near me, but I might hold off and read more about the VST one, if it's much better than the Gaggia part. We'll probably end up using both though. I want to learn more and play with the machine, my girlfriend just wants a shot of coffee with minimal fuss. So I'll experiment the non-pressurised and leave her with the stock basket and plastic disc. I'm not sure how much more coarse than a 'proper' espresso grind we should go for with the pressurised basket though? Is the stock basket quite forgiving?

And I'll be interested to see a side-by-side on the new and old model when you've done a comparison.


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## jimbojohn55 (Jan 15, 2016)

Jumbo Ratty said:


> didnt think VST did a 14g
> 
> If you do get a VST get ridgeless,, ive got the 15g VST ridgeless couldnt be happier


15g vst - that's what I meant - been a long day


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## tdfg7583 (Nov 16, 2016)

By the way, with the 15g VST, will I need another tamper, or would a 58mm do the trick?


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## jimbojohn55 (Jan 15, 2016)

tdfg7583 said:


> By the way, with the 15g VST, will I need another tamper, or would a 58mm do the trick?


Will do fine, but keep an eye out for a 58.4mm one, they make life alot easier

I think ther was one on the sales forum at weekend by dfk41


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## tdfg7583 (Nov 16, 2016)

jimbojohn55 said:


> Will do fine, but keep an eye out for a 58.4mm one, they make life alot easier
> 
> I think ther was one on the sales forum at weekend by dfk41


Great, I'll keep an eye out then!


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## tdfg7583 (Nov 16, 2016)

By the way, with the VST basket, do you always weigh the dose for 15g exactly, or just level to the rim before tamping?


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## Jumbo Ratty (Jan 12, 2015)

tdfg7583 said:


> By the way, with the VST basket, do you always weigh the dose for 15g exactly, or just level to the rim before tamping?


VSTs are weight sensitive,, thats why they are rated as being able to only go 1g either side of the stated weight. Some beans take up more room in the PF when ground than others.

Please take the small amount of time it takes to weigh the ground beans that are going into the VST, it'll become second nature in no time


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## hotmetal (Oct 31, 2013)

VST baskets are good for a dose +/- 1g from nominal. You should weigh accurately using jewellery scales and keep the dose within the design range of the basket. Too little and you'll very likely get channeling and gushers, too full and there will not be sufficient headroom for the brew - also if you pack it too full, when the grounds expand it could cause excess pressure, which will slow down the shot even more, and will make your timings out and possibly lead to a choke, or at least a poor extraction.


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## tdfg7583 (Nov 16, 2016)

Thanks for the great info! This place is helping a lot to get orientated.

Are the standard Gaggia double baskets (non-pressurised) any more forgiving of experiments with slightly up- or down-dosing? Are they optimised for 14g, I guess?

I guess that scales will be next on my shopping list then!


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## Jumbo Ratty (Jan 12, 2015)

tdfg7583 said:


> Are the standard Gaggia double baskets (non-pressurised) any more forgiving of experiments with slightly up- or down-dosing? Are they optimised for 14g, I guess?
> 
> I guess that scales will be next on my shopping list then!


I "think" the gaggia double baskets are actually bigger than 14gs, but also I "think" they have varied over the years.

The scales can be had for less than £5 delivered.

Get ones that go from 0.1 - 1000 gs then you can weigh big cups under the PF or even weigh the entire PF when grinding direct into it


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## MartinB (May 8, 2011)

I'd love to get my hands on a 2015 model and see what components can be retrofitted!


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## Jumbo Ratty (Jan 12, 2015)

MartinB said:


> I'd love to get my hands on a 2015 model and see what components can be retrofitted!


Ive got both types,, and the answer is none that i know of,, maybe the pumps the same


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## MartinB (May 8, 2011)

Got a picture of the internals at all?


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## jimbojohn55 (Jan 15, 2016)

MartinB said:


> Got a picture of the internals at all?


The red arrow is the 2015 OPV (which many say it does not have .... gaggia just hid it for a laugh.


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## Jumbo Ratty (Jan 12, 2015)

heres a few

how the wand just disappears










internals


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## tdfg7583 (Nov 16, 2016)

Just checked my pressure with a gauge attached to the portafilter, with no basket. Up to a little over 11.5 bar. Not the 10 bar I was hoping for.

Has anyone successfully adjusted a 2016 model? I'm not at all sure how to go about correcting it. I know the above image has an arrow to the 'new' OPV but I thought I read elsewhere about people adjusting a spring and I can't see any spring on that part. I'm not that technically minded, sadly. I'm a little worried about loosening something and causing a leak.

How much difference will it make at 11.5 bar? Will I find it hard to get the best results from the VST basket with finer grinds? I'd read that higher pressure can cause channelling or over extraction of more bitter flavour compounds?


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## Jumbo Ratty (Jan 12, 2015)

tdfg7583 said:


> Just checked my pressure with a gauge attached to the portafilter, with no basket. Up to a little over 11.5 bar. Not the 10 bar I was hoping for.
> 
> Has anyone successfully adjusted a 2016 model? I'm not at all sure how to go about correcting it. I know the above image has an arrow to the 'new' OPV


 The part you need to adjust for the pressure is the OPV valve.

The thread link I posted a few posts back does contain a detailed video of it being done. Go through that thread and you should find it.

Heres another video that shows it done on a gaggia baby, which shares the same OPV,,, not sure it stick that glue like stuff on like the chap does in this video,, bit too permanent.








tdfg7583 said:


> I thought I read elsewhere about people adjusting a spring and I can't see any spring on that part.


I think the spring is inside the OPV and as you're not actually taking the thing apart you wont access it anyway.

You just need to back the nut off slightly with a 10mm spanner.

I think its very sensitive, so only slight adjustments needed.


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## jimbojohn55 (Jan 15, 2016)

watching the vid - I can only think that he had a leak if not then if it was loose why not just add some ptfe tape or some instant gasket.


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## Jumbo Ratty (Jan 12, 2015)

He says it was slack and he wanted to secure it in place with no leaks.

I guess once the tops back on it may over time move from the 10bar its set to. So that milliput gives peace of mind it will stay put

Not a bad solution. Just cant imagine it easily reversible. But then why would you reverse it? so maybe thats the best solution.


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## tdfg7583 (Nov 16, 2016)

Just tried adjusting the nut. Backed it off very roughly one turn and that brought the pressure at the portafilter down to 10 bar. Good stuff! Thanks for all the advice







My coffee still tastes terrible, but at least I know now that's my fault, haha.

At the moment, I haven't secured or sealed it and there is no leak. It seems fine. Would you seal it to be safe, or leave it so it's easy to adjust in future?


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## jimbojohn55 (Jan 15, 2016)

tdfg7583 said:


> Just tried adjusting the nut. Backed it off very roughly one turn and that brought the pressure at the portafilter down to 10 bar. Good stuff! Thanks for all the advice
> 
> 
> 
> ...


personally I would leave it - what I would do (which you may have already) is disconnect the pipe and then reattach - this should prevent any movement of the nut

Cheers for having ago! -

ps keep an eye on it for leaks


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## jimbojohn55 (Jan 15, 2016)

Just a thought you should start a new thread in the Gaggia forum for others to reference (Gaggia 2015 - adjusting the OPV pressure to 10 bars)- using jumborattys pics and your experience of the process


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## tdfg7583 (Nov 16, 2016)

Will do, thanks.

Now the machine is set up, I think my next task is to understand a bit better about temperature surfing and whether it's necessary on the 2015 for consistency of pulls (I only make espresso and don't use the steam wand). And then I'll be on to playing with doses and grind sizes until I can get a decent shot out of the thing!


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## jimbojohn55 (Jan 15, 2016)

I would go for the grind size and dose first and then the temp surfing - at least you will have coffee that's good while you fiddle ;-)


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## Jumbo Ratty (Jan 12, 2015)

id put a pen mark on both the nut and the plastic, so as to give you a visual aid so you can just look at it and know it hasnt crept off the correct setting.

But also do the pipe disconnect \ connect as that sounds like a credible idea.

Id be tempted to maybe experiment with going down even lower in pressure before milliputting it forever more once and for all at 10 bar


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## tdfg7583 (Nov 16, 2016)

Thanks. Again, being a complete newbie, just literally pull off the clear tube and then push it firmly back on again? No other fixing required? I would previously have imagined that a 15 bar pump would want more than a simple push fit to secure itself, but I have no idea about these things


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## tdfg7583 (Nov 16, 2016)

jimbojohn55 said:


> I would go for the grind size and dose first and then the temp surfing - at least you will have coffee that's good while you fiddle ;-)


Fair point, haha.


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## jimbojohn55 (Jan 15, 2016)

tdfg7583 said:


> Thanks. Again, being a complete newbie, just literally pull off the clear tube and then push it firmly back on again? No other fixing required? I would previously have imagined that a 15 bar pump would want more than a simple push fit to secure itself, but I have no idea about these things


yes it should be possible - hang in let me do mine first - don't want you to bugger it up now you've got this far - back in a couple of mins


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## tdfg7583 (Nov 16, 2016)

Thanks







Likewise though! Don't force anything on your machine on my account if it's already set up nicely for you.


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## Jumbo Ratty (Jan 12, 2015)

tdfg7583 said:


> just literally pull off the clear tube and then push it firmly back on again?


I'd be inclined to put a large flat head screwdriver in the gap between the end of the pipe and the nut and lever the pipe as well at the same time as you pull it so it doesn't get stretched \ stressed


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## jimbojohn55 (Jan 15, 2016)

Not a problem ive got two on the go - pipe comes off with a bit of a tug - but don't bother - because of course the pipe just feeds back into the water tank so it will have turned with the nut anyway - DUH - slaps own forehead - just mark it and keep an eye on it to see if it moves like jumbo said


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## tdfg7583 (Nov 16, 2016)

Even easier then







Great. And thanks for checking it out for me anyway. Very much appreciated.


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## Jumbo Ratty (Jan 12, 2015)

jimbojohn55 said:


> * but don't bother* - because of course the pipe just feeds back into the water tank so it will have turned with the nut anyway - DUH -


LOL,, i was even looking at my photo thinking you could trim the 10mm off the end of the pipe that originally went onto the OPV so when you re-attach it it has a nice tight fit again because there looked enough slack in the pipe


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## jimbojohn55 (Jan 15, 2016)

I think its Grrrrreat how on the 2015 machine they have made it even easier to adjust the OPV valve - but kept really quiet about it being adjustable and the fact that the machine ships at nearer 10 Bar than the advertised 15 Bar - God Bless Philips


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## Iron67 (Aug 14, 2018)

Hi,

I recently bought this classic (RI9403/11), and I apologize to you if I have little experience.

I am aware that the optimal use would require an unpressurised basket, a grinder and an adequate tamper, but space and budget are not currently favorable.

Now I have a default configuration and I'm trying some pre-ground commercial blends (Pellini, Segafredo and Vergnano). The results are scarce, in fact, the coffee comes out underneath, fast and with little cream.

I tried to lower the pressure by adjusting the OPV (unscrewing the nut one turn) but almost nothing changed. How much can be unscrew without doing damage?


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## GCGlasgow (Jul 27, 2014)

The problem is probably more with the pre ground coffee you're using, controlling the flow by adjusting the pressure won't make it compatible with pre ground,


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## ashcroc (Oct 28, 2016)

Iron67 said:


> Hi,
> 
> I recently bought this classic (RI9403/11), and I apologize to you if I have little experience.
> 
> ...


If using pre-ground, you're best off with the pressurised basket.


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## Iron67 (Aug 14, 2018)

ashcroc said:


> If using pre-ground, you're best off with the pressurised basket.


Apologizing for the question, with two meausring of well-pressed preground coffee, compressed basket, I have a shot of 16 seconds since I start the pump. Is it normal?


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## GCGlasgow (Jul 27, 2014)

16 secs is probably a bit quick but if it tastes OK then stick with it. When grinding beans at home small adjustments have to be made a lot, so with pre ground you can't change it if it's not suitable.


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## Iron67 (Aug 14, 2018)

I would like to avoid buying an expensive grinder that also occupies space in my small kitchen.

The pre-ground espresso blends should be suitable with standard machines (pressure 9 bar in the group) but with this Classic they do not perform well.

This thing seems incredible to me. I'm disappointed by this machine, a Nespresso costs a quarter and makes a much nicer coffee.









I would like to understand if the replacement of the OPV could improve the situation, but as I have read, pressure is not the only parameter that comes into play.

Is it possible to electronically slow down the flow produced by the pump?


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