Hiss just after pre-infussion

[ebprod]

My VII has been making a hissing sound just after the pre-infussion. I only notice it if the porta-filter isn't in. It only lasts a second, and doesn't seem to affect the taste of the coffee. Is this normal?

I only noticed after making two changes. First, I changed both the filters- I use Chris's system. Also, I changed my machine to 20amp operation.

I can't tell if the hiss is air, or overheated water. Any ideas?

-Joe

[JohnB]

Did you bleed the line thoroughly after changing the filters? I've never noticed the hiss on my V2.

[Niko]

Do you mean a slight "Pssssss" sound?
This is normal, I get it on both machines.

Also nice to hear you now have a dual boiler machine, Joe
20A operation sure is nice and I'm reminded of this every time I fire up the old S1. It's running on 15A for a while until we run a dedicated breaker soon. The machine just isn't the same

[JohnB]

The only noise I hear is the pump kicking in & that continues throughout the shot.

[Niko]

There are definitely sounds happening if you listen closely, the progressive P/i sounds like a rocket launcher when you backflush. A huge, long "PfffSSShhhhhhhh" following when you cut off the pump. The VII is very subtle so I'm not surprised most people don't hear it, then again (like John mentioned) there could be some air trapped in the lines from changing the filters. This should work itself out, Joe.

[ebprod]

I am getting the noise after the pre-infusion, just as the pump kicks in for the shot. I am pretty sure the sound is new, so maybe it is just the new filters.

-Joe

There are definitely sounds happening if you listen closely, the progressive P/i sounds like a rocket launcher when you backflush. A huge, long "PfffSSShhhhhhhh" following when you cut off the pump. The VII is very subtle so I'm not surprised most people don't hear it, then again (like John mentioned) there could be some air trapped in the lines from changing the filters. This should work itself out, Joe.

[ebprod]

Niko,

I have had my S1 for about 1 1/2 years now. I gave my Isomac Relax to my daughter when she got her own apartment.

I have been using it on 15amp mode mainly because I was too lazy to find out if it was a 20amp circuit. After some investigating I found that I only had the one outlet on the 20amp circuit. I haven't noticed much of a difference, but I mainly do straight shots. My wife mostly makes milk drinks, but since it is usually just one at a time, she hasn't noticed a big difference. I'm sure the next time we have friends over it will be of great benefit.

Also nice to hear you now have a dual boiler machine, Joe
20A operation sure is nice and I'm reminded of this every time I fire up the old S1. It's running on 15A for a while until we run a dedicated breaker soon. The machine just isn't the same

[Niko]

You will notice the big difference only with the milk drinks, espresso only is no change whatsoever. Low volume milk drinks is just fine, 1-2 or 3-4 drinks is OK but anything beyond that is going to be a little on the slow side. I'm constantly waiting for the machine on Economy Mode for Cappas, I do milk at the same time as the shot pulls into the cups so you can imagine the frustration when you need to bang out 20 Cappas at a busy party (people grow impatient quickly).
Joe, you still getting that hiss?
Post a sound file or a vid clip (with sound) on Youtube or something so we can listen to it.

[ebprod]

This hiss seems to have gone away. I can only assume that it was from air when I changed the filters. In any case, everything is back to normal.

-Joe

Joe, you still getting that hiss?
Post a sound file or a vid clip (with sound) on Youtube or something so we can listen to it.