I am trying to decide between the Rocket Giotto Premium Plus and the Giotto Evoluzione. One of the first things I noticed is that the Evoluzione comes with two gauges on the front. One gauge is the pressure at the boiler which both models have and the second one is the pressure at the brew head which only the Evoluzione has.

How important is the pressure at the brew head gauge? Is it really necessary? This is the first espresso machine I'm going to buy and I just want to know if it's worth it to spend the extra $400 on the Evoluzione. I know the Evoluzione comes ready to be plumbed as an option, but I'm not planning on doing that.

Thx in advance.

F1 wrote:How important is the pressure at the brew head gauge? Is it really necessary?

*shrug* It's nice to have, but a portafilter pressure gauge serves the same purpose. I've owned La Valentina for years; I check the brew pressure a couple times a year, but otherwise don't give it much thought. On the other hand, I monitor the steam boiler pressure because it delivers more pressure when steaming milk if you start at the peak of the heating cycle (unnecessary for commercial espresso machines because the boiler has significant heat in reserve).

another_jim wrote:What you call pressure at the brew head is the pump pressure. It can be adjusted via the OPV (search to find out what I'm talking about). If you don't have it in the machine, you'd need to buy a gauge to mount to the portafilter to occasionally check the pump.

The normal gauge shows the steam pressure inside the boiler, and it tells you the heat is running. Boiler pressure also can be adjusted, but its effect on espresso taste is somewhat indirect.

I apologize for sounding condescending, but you can save yourself some grief by reading up (in the guides you were told to read when signing up) before either posting or trying to use your machine.

Is the portafilter gauge as accurate as the ones that come integrated with the machine?

Where can I get one of those? I checked on the website(Seattle Coffee Gear) where I'm planning to buy the machine from, but I couldn't find anything like it.

HB wrote:*shrug* It's nice to have, but a portafilter pressure gauge serves the same purpose. I've owned La Valentina for years; I check the brew pressure a couple times a year, but otherwise don't give it much thought. On the other hand, I monitor the steam boiler pressure because it delivers more pressure when steaming milk if you start at the peak of the heating cycle (unnecessary for commercial espresso machines because the boiler has significant heat in reserve).

Thx for the info.

F1 wrote:Is the portafilter gauge as accurate as the ones that come integrated with the machine? Where can I get one of those?

Portafilter pressure gauges are more accurate than built-in gauges since they measure directly at the brew head. Built-in ones typically read slightly higher than the actual pressure at the brew head because they are tee'd in prior to the grouphead gicleur (orifice). Try searching on portafilter pressure gauge kit for resellers, ask your preferred vendor, or just build your own.

F1 wrote:Is the portafilter gauge as accurate as the ones that come integrated with the machine?

Gauge accuracy is a product of the gauge and the care with which it is maintained. Since the built in gauges are in the "Cheep and Cheerful" class and several orifices away from the puck, their accuracy is highly suspect. OTOH, with a vibe pump, pressure is highly dependent on flow, so if you build your own, you MUST limit the flow to shot volumes. Swagelok makes some very nice valves for precision flow control at high pressure.