# Surge after 5 seconds?



## Moor (Sep 14, 2016)

I'm having problems with my duo temp pro, I'm not sure if it's me or the machine, I'm guessing it's me though. I'm getting issues that after about 5 seconds of a decent extraction, nice and smooth I get a change in tone of the pump, it gets louder and the coffee comes through much quicker and full of bubbles. It doesn't happen every time but more often than not.

This is a fairly recent phenomenon, I have had the machine nearly a year and only started this a couple of months ago. My gut tells me it's me tamping incorrectly but I don't feel I'm doing anything different, I have been experimenting with different beans but other than that it's been the same as ever. I'm using a sage pro grinder, the grind varies from 12-14, and just under 14 second grind time.

Any suggestions are greatly appreciated, I'm tired of awful coffee!


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## joey24dirt (Jan 28, 2017)

The first part is the pre infusion then it kicks up to full pressure after that. Completely normal


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## filthynines (May 2, 2016)

Joey - I'm not so sure. OP says that it's five seconds after extraction begins.

@Moor - Could do with seeing a video of what you mean, because it's not entirely clear. But from your description I think you're not grinding finely enough. I have the combo you have, and the coarsest grind setting I use is 7. Anything more is just too coarse.

Without any specialist knowledge whatsoever it sounds to me as though there's a sudden release of pressure, which I would firstly attribute to the grind.

Will you tighten up the grind and then report back, please?


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## Moor (Sep 14, 2016)

Thanks, I will try a finer setting and see. It's not the pre infusion phase, I get that is normal, this is after extraction starts. I will try the finer settings and record too and report back


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## Obnic (Jan 14, 2014)

Sounds like channeling. Only bit that puzzles me is the bubbles bit. Not sure why you would get foam unless the pump is sucking air along with water.

If it's channeling then usual suspects are overdosing the basket (shower-screen interfering as puck expands) or distribution issues. I'd nail this area down first.

If the pump is sucking air once the basket is under pressure then I'd be looking at water pipes for pinholes and for loose connectors.


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## joey24dirt (Jan 28, 2017)

Ah sorry yes I've read the post again @filthynines. As mentioned a video would be useful  currently on my grinder I'm set on 1 on the burrs and 12-13 on the dial. I could possibly go finer with this bean also.


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## Rakesh (Jun 3, 2017)

1) What basket are you using?

2) How coarse is your grind?

3) How firm are you tamping?

4) Time your shot, how long is the pre-infusion lasting (how long until you hear the pump kick up to full pressure)?

5) Are you using the razor dosing tool?

6) When this happens, are you sure the water tank isn't below minimum?

There's a handful of reasons this could be happening, the more details you provide, the more accurately we will be able to suggest some solutions.


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## Moor (Sep 14, 2016)

My thoughts are channeling too, not sure why it's only coming to light now though. I can't hear any air sucking it so I don't think there's a leak anywhere, it's not really bubbly enough for me to suspect that, more like heavy foam than bubbles.

i have dialled down to 6 on the grinder and got no coffee out, upped it to 8 and marginally better so I will try 9 and 10 tomorrow and see how they do, better tasting coffee though, much less bitter.

to answer rakesh, I'm using the single walled double basket, grinding to 13, I have been experimenting with finer as mentioned above, I'm thinking this is my issue. I don't time but it's around 20 seconds which also lends to my grind being too coarse. I use the razor tool now and again, I'm pretty good at seeing and feeling with tamper when it's the right amount, I use medium firm pressure, roughly 30lbs from testing on the bathroom scales.

Thanks for all the replies so far.


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## joey24dirt (Jan 28, 2017)

Moor said:


> My thoughts are channeling too, not sure why it's only coming to light now though. I can't hear any air sucking it so I don't think there's a leak anywhere, it's not really bubbly enough for me to suspect that, more like heavy foam than bubbles.
> 
> i have dialled down to 6 on the grinder and got no coffee out, upped it to 8 and marginally better so I will try 9 and 10 tomorrow and see how they do, better tasting coffee though, much less bitter.
> 
> ...


How fresh are your beans? Do you stick to the same type? Have a look in the DTP owners thread. There's a video link of a shot being pulled on there which might be a good comparison for you


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## Rakesh (Jun 3, 2017)

Moor said:


> My thoughts are channeling too, not sure why it's only coming to light now though. I can't hear any air sucking it so I don't think there's a leak anywhere, it's not really bubbly enough for me to suspect that, more like heavy foam than bubbles.
> 
> i have dialled down to 6 on the grinder and got no coffee out, upped it to 8 and marginally better so I will try 9 and 10 tomorrow and see how they do, better tasting coffee though, much less bitter.
> 
> ...


Try not to use the razor tool, its designed to be used after tamping the puck and can cause cracks in your puck leading to channeling. Tamp as firm as comfortably possible and try to focus on getting a nice even tamp rather than worry about how much pressure you are using. Start timing all of your shots, aim for around 18g in to 36g in the cup in around 30 seconds, then adjust to taste from there. As for the bubbles when I use coffee that hasn't rested long enough I get some small bubbles in the crema, however the heavy foam you are describing is probably a result of a very channeled shot causing a fast flow resulting in bubbles or foam. Most importantly, how do these shots taste? Over-extracted (bitter, dry, astringent) or under-extracted (sour, salty), if under-extracted its's most probably due to a coarse grind and channeling.


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## Moor (Sep 14, 2016)

If I do use the razor tool it's usually to to clean the edges of the basket rather than level the puck. Your description of the foam/bubbles from channeling sounds very similar to what I'm experiencing. I use fresh coffee beans purchased from coffee masters in amazon, I have been trying their various blends which is when I met my current issues. I am getting quite bitter coffee, not noticeably sour and definitely not salty. I am currently playing around with grind levels, I will do some weighing too.


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## Obnic (Jan 14, 2014)

Weighing in and out seems like a schlep when you first start but (assuming you use fresh beans) it really is the thing that will progress your coffee making more than anything else.


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## joey24dirt (Jan 28, 2017)

Moor said:


> If I do use the razor tool it's usually to to clean the edges of the basket rather than level the puck. Your description of the foam/bubbles from channeling sounds very similar to what I'm experiencing. I use fresh coffee beans purchased from coffee masters in amazon, I have been trying their various blends which is when I met my current issues. I am getting quite bitter coffee, not noticeably sour and definitely not salty. I am currently playing around with grind levels, I will do some weighing too.


I used to get those beans off amazon. The beans supplied off amazon were never as fresh as getting them direct from coffee masters.


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## Moor (Sep 14, 2016)

I will start weighing, I have a set of scales sat on top of the machine, I have been loathe to use them but if it helps I will give it a go.

i did have a look at beans direct from coffee masters, I can only find them in packs of 6 though which is far more than I need, I use amazon as I have prime and it makes my life easier. Any other amazon suppliers worth looking at?


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## Obnic (Jan 14, 2014)

Try Richard Jansz at coffeecompass.co.uk

He sells 500g bags at very keen prices with a flat £3 delivery for one bag or £4 for more. With the forum discount postage can be free if you buy several bags at a time and freeze some of the beans. The beans will be sent the day they're roasted and with you the next day. At least as good as AmazonPrime for top quality fayre.

He's a really nice chap who will help you select beans you'll enjoy too. [email protected]

And I can't commend this guide to weighing (brew ratio) highly enough. You probably know it already but 'well warf annuver gander'.

https://coffeeforums.co.uk/showthread.php?22879-Beginners-Reading-Weighing-Espresso-Brew-Ratios


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## joey24dirt (Jan 28, 2017)

Moor said:


> I will start weighing, I have a set of scales sat on top of the machine, I have been loathe to use them but if it helps I will give it a go.
> 
> i did have a look at beans direct from coffee masters, I can only find them in packs of 6 though which is far more than I need, I use amazon as I have prime and it makes my life easier. Any other amazon suppliers worth looking at?


I'm sure they are at least a month old before they get to you through prime so maybe it's a slightly older batch causing these problems.

I'd have a look at what @Obnic has suggested. I'm pretty lucky to have a roaster close by so I just use them and get through 1kg bags before they start to go stale.


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## Moor (Sep 14, 2016)

Thanks very much for that, I will have a look. How well do beans freeze?


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## Obnic (Jan 14, 2014)

Moor said:


> Thanks very much for that, I will have a look. How well do beans freeze?


Well that's a big discussion.

For a while many people felt you shouldn't freeze. More recently, folk have been letting their beans gas off, then freezing them and grinding them from frozen for better particle distribution.

I freeze because I buy lots and import into Switzerland in batches. I put the unopened packet in an IKEA ziplock bag, suck out all the air and freeze. Other folk just seal the valve. Others use vacuum jars or sous-vide vacuum sealers.

My bags are never in the freezer more than ten weeks, more likely less than four weeks. I get through c.500g per week. This has worked perfectly well for me.

I did once store a bag for eight months and it was nasty.


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## Moor (Sep 14, 2016)

Well after a couple of weeks playing, with a holiday in the middle, I am getting much better results. I have gone back to my favoured beans (coffee masters master blend), I have dialled the grinder down finer (7 at present) and I have weighed in and out along with timing my shots. The end result is no surging, better tasting coffee, which also has to do with the beans, but overall I'm much happier.

I have been using the machine for nearly a year and thought I was getting half decent results, however what I'm getting now is far better so thanks to all for the help and guidance, I can't believe I was getting it so wrong for so long.


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