I have finally built a manometer attachment to the portafilter, but it is late here and I wanted to give it just a quick go on my Promac http://www.home-barista.com/espre...omatic-t10820.html I only opened a water to the machine, switched on (did not switch on the heating elements), put the portafilter in place, switched the "make the espresso" button, and nothing happened with the needle of the manometer. It did not move one bit.



I tried it with basket on, basket off, with valve opened (water flowing) and valve closed—no change.

Do you know where the problem could be? Should I just try to switch everything in the morning, including heating element? Will it make a difference?

Other questions:
1) the manometer is a glycerin one, is it normal that there is a big bubble of some gas in the liquid?
2) would it hurt the manometer if the measurements are made with a boiling water?

Thank you for the replies. I am trying to read the different topics here for an hour, but could not find an answer.

HB wrote:I assume the gauge orifice is blocked.

Thank you for your replies. That is odd. There is nothing I could think of, that could block the gauge orifice. I will unscrew it and have a look again.

EDIT 1: I have unscrewed the manometer, and the hole is clean. When I screwed it back in and put it into the machine, there was again nothing. Then I waited for 10 seconds, and finally it moved. But it stopped at 3.5 bars after like 2-3 seconds slow moving from zero and then the seal between the group and portafilter began to leak.



That is odd, because when I do backflushes, it does not leak. I have tried with basket, without basket, fixing the portafilter as strong as I could (pushing the handle to the right). Still leaks and I can't get above 3.5 bars.

What could be wrong now?

EDIT 2: I tried to put the rubber disk (as for backflush) in a basket with a DIY thingy, and it still leaks. But when it is in another basket—it does not (kept it under pressure for 20+ seconds). So I guess there could be a problem with the portafilter itself? I will try to screw my DIY portafilter gauge on another portafilter after I get home from work.

Or do you have any other ideas?

HB wrote:Since there's no basket, the lock-in position will shift and the mating surface is smaller. If the grouphead gasket is old, it's more likely to leak. That said, it is not a reason for concern since drip drip drips while measuring pressure will not change the reading, especially on rotary pumps (they're readings are unaffected by flow rate since they're dramatically over-capacity).

It is the same either with or without basket—drips anyway. The gasket rubber is 2 weeks new. So if I understand correctly, the measure I get is a correct one? 3.5 bars of pressure? The manometer is brand new. So should I trust it and increase the pump pressure? I wonder then, how was I able to prepare espressos with such a low pressure

Should I buy yet another manometer, to make sure this one is accurate? Or is there something in the design of my portafilter gauge (or the method I use it) that somehow shows me the results 2x-3x lower?

Hi Vad,

it might be leaking with the basket because the water goes through the basket hits the gauge and actually goes back up and finds it's way out underneath the basket where it touches the PF. When measuring pressure with a PF gauge I always remove the basket and stick a basket-less (yeah like that's a word) PF into the group making sure it sits tightly against the group gasket.

What pump does you machine have, rotary or vibe?

Regards,
dsc.

dsc wrote:it might be leaking with the basket because the water goes through the basket hits the gauge and actually goes back up and finds it's way out underneath the basket where it touches the PF. When measuring pressure with a PF gauge I always remove the basket and stick a basket-less (yeah like that's a word) PF into the group making sure it sits tightly against the group gasket.

What pump does you machine have, rotary or vibe?

I have tried both ways, with basket or without, the pressure on the manometer and the dripping is the same. I have a rotary pump, here is my machine http://www.home-barista.com/espre...omatic-t10820.html

I am starting to be clueless. I could try another portafilter when I get home, but as HB said, the dripping would not make difference pressure-wise. And 3.5 bars—is it something wrong with manometer and measurement technique/device, or the pump in a machine is set VERY low?

I would not make any adjustment to the pump until this pressure problem is resolved. What is the flowrate from the pump (ml/minute) when simply flushing?

Please describe the water hook-up to the espresso machine.

What is the normal pressure in your main supply line (house system)? You could always find an inexpensive gage and compare it with the PF gage you have testing the same source, i.e. house mains pressure.

erics wrote:What is the flowrate from the pump (ml/minute) when simply flushing?

It is about 60 ml in 10 seconds.

erics wrote:Please describe the water hook-up to the espresso machine.

Water outlet for a washing machine > flow restrictor > decalcifier > espresso machine. Should I measure the water pressure from the water outlet? Then from behind the water flow restrictor? (speaking simply the water from the wall outlet has a hell of a flow)

erics wrote:What is the normal pressure in your main supply line (house system)? You could always find an inexpensive gage and compare it with the PF gage you have testing the same source, i.e. house mains pressure.

I don't know what the pressure is. I will have somehow to connect the manometer from my DIY thingy to the water outlet (as I said in a previous paragraph).

What is the recommended bar pressure of a water flow into the machine (in my case what pressure should I have between the water flow restrictor)? So that I can setup it right and eliminate this variable.

Thank you all for your suggestions, I very much appreciate it.