La Pavoni Europiccola, first shot a bit sour

A haven dedicated to manual espresso machine aficionados.
Katzer
Posts: 82
Joined: October 25th, 2016

Postby Katzer » Jan 01, 2017, 2:09 am

Hi all,

I am looking for a tip on getting the group hot enough as my first shot of the day is usually a bit sour, indicating that the temperature is on the low side.

Subsequent shots are better.

It is a Milennium Europiccola, with the Rython sleeve, I upgraded the piston to brass.

I can run more water through but the boiler is small and I can get half the water out very fast. I thought of using the single basket, either for a sink shot (i hate the waste) or maybe plugging it so it would introduce some resistance to the water flow so it stays longer in the group.

My routine is usually turn the machine on, take the dog for a short walk, by the time we are back the red light is off, i bleed some pressure (4-5 seconds) from the steamer, some pressure from the group. At that point the machine starts heating up again, I wait for the red light to come out again and then proceed to pulling the shot.
I think it is pretty much standard.

Any advice?

Happy 2017!
Erez

wsfarrell
Posts: 384
Joined: October 1st, 2012

Postby wsfarrell » Jan 01, 2017, 2:18 am

I have only limited experience with a restored Cremina (with teflon gasket), but I've noticed that the first shot is reliably hotter after the machine has been on for an hour, as opposed to 10 minutes when the light goes out. No flushing in either case.

Seacoffee
Posts: 329
Joined: February 23rd, 2012

Postby Seacoffee » Jan 01, 2017, 2:22 am

Happy New Year Erez,

If you don't already, keep the portafilter holder in the group. this will then become part of the group and keep it hotter and will not cool down as much when you put the shot. Put the basket in just before you pull the shot.

Maybe wait a little longer maybe for the third red light. Certainly waiting longer before you make a shot will make it hotter as Bill has said. Jut because the the pstat has activated does not mean the temp has stabilised in the machine. It takes more time to get every part of the machine up to temp.

Maybe grind a little finer for a slightly longer shot should also remove some of the sour.

User avatar
dominico
Team HB
Posts: 1673
Joined: November 8th, 2014

Postby dominico » Jan 01, 2017, 4:59 am

Hey there.

The easiest thing for you to do would probably be to add either a group thermometer or a temp strips to your group. This way you will always know if your group is running hot, cold, or at the right temp.

Here is a thread of many different ways people have attached digital thermometers to their Pavoni's.
Adding Thermometry to a La Pavoni Europiccola

A lower cost / lower hassle version, albeit somewhat less precise, is to get a temperature sensitive sticker.
https://www.espressocare.com/search?key ... ture+strip


As for some techniques on general: it is always a good idea to bleed trapped air from the boiler before your first shot. You do this by opening the steam wand and pumping the lever a few times, lifting it to just below where water would start pouring out of the group, then closing the steam wand again. This will both improve your preinfusion for that first shot and cause the heating element to kick in again.

In order to further warm up the group ypu can perform those sort of half pumps in general, even with the steam wand closed, which will cycle water between the group and boiler further warming up the group.
http://bit.ly/29dgjDW
Il caffè è un piacere, se non è buono che piacere è?

User avatar
rpavlis
Posts: 1805
Joined: January 8th, 2012

Postby rpavlis » Jan 01, 2017, 9:07 am

With first and third generation La Pavoni machines the group is heated by having hot water around the sleeve. If you first raise the piston, just for an instant, enough to release just a bit of water, then lower it and make several partial pumps hot water will go into and come out of the boiler with each partial pump. Do NOT raise the lever enough to release any water during this process. I have always preferred digital infrared thermometers because they provide instant reading and there are not problems of heat transfer. If you have a brass version with a polymer coat, you can simply point the thing at a determined point on the group and get an instant temperature. If you have a chromed version, you will need to stick some sort of tape to a point, the thinner the better.

If you roast your own you can also roast a bit darker. You can also make a "partial" pull at the start. Espresso making is a somewhat crude chromatography, and most of the bitter tasting components elute slower, so a "longer" shot will be more bitter. A smaller dose will also be more bitter, because the water has to travel through a thinner section of grounds.

Espresso drinkers vary a LOT on what they consider too sour and what they consider too bitter.

Because first and third generation machine groups are heated mostly by water around the sleeve, they tend to be more temperature stable than second generation machines in which the top of the group is always filled with live steam. If one fail to bleed the SECOND generation machines temperature tends to be extremely erratic, and with first and third it is just a bit erratic!

Just remember partial pumps with either a first or third generation machine tends to heat up the group very quickly.

Katzer
Posts: 82
Joined: October 25th, 2016

Postby Katzer » Jan 03, 2017, 7:22 am

Thank you all.
@rpavlis:
what exactly do you mean by partial pumps?

Erez

Seacoffee
Posts: 329
Joined: February 23rd, 2012

Postby Seacoffee » Jan 03, 2017, 7:44 am

Lift the lever up to just before the point where water begins to enter the cylinder, which is almost to the top. Do this a few time. This will move the water from the boiler itself to around the group and heat the group closer to boiler temp.

User avatar
dominico
Team HB
Posts: 1673
Joined: November 8th, 2014

Postby dominico » Jan 03, 2017, 11:54 am

Katzer wrote:@rpavlis:
what exactly do you mean by partial pumps?

Erez


He means the half pumps that I described in my post above, the description was kind of buried in my explanation about bleeding trapped air from the boiler.

dominico wrote:Hey there.
As for some techniques on general: it is always a good idea to bleed trapped air from the boiler before your first shot. You do this by opening the steam wand and pumping the lever a few times, lifting it to just below where water would start pouring out of the group, then closing the steam wand again. This will both improve your preinfusion for that first shot and cause the heating element to kick in again.

In order to further warm up the group ypu can perform those sort of half pumps in general, even with the steam wand closed, which will cycle water between the group and boiler further warming up the group.
http://bit.ly/29dgjDW
Il caffè è un piacere, se non è buono che piacere è?

User avatar
mwebber
Posts: 19
Joined: December 18th, 2016

Postby mwebber » Jan 03, 2017, 12:48 pm

rpavlis wrote: I have always preferred digital infrared thermometers because they provide instant reading and there are not problems of heat transfer. If you have a brass version with a polymer coat, you can simply point the thing at a determined point on the group and get an instant temperature. If you have a chromed version, you will need to stick some sort of tape to a point, the thinner the better.


Do you have any recommendations for a digital infrared thermometer, or will any sort do? Do you have any photos of where on the group you're sticking the tape or measuring the temperature?

User avatar
rpavlis
Posts: 1805
Joined: January 8th, 2012

Postby rpavlis » Jan 03, 2017, 1:59 pm

Here is a picture of my second generation machine with an arrow indicating the point where I point the laser when I read temperatures. I like to have the thing horizontal to the group when I pull its trigger. The ones I have say "Nubee" on them.

Image

I tend to measure temperatures a bit higher up on my 1964 first generation machine, at the top of the flare, rather than bottom.

The image shows my 2nd generation pressurestat machine, I like to have the pressure near 0.7 bar. (Which is the reading when image was made.) From time to time I use special caps I made to measure pressure and temperature, as shown here. Normally I use a simple brass and wood cap I made.)

 
Sponsored by intelligentsiacoffee.com
www.intelligentsiacoffee.com: home of the black cat project