Lelit Elizabeth pressure jumps during a shot

Equipment doesn't work? Troubleshooting? If you're handy, members can help.
robotshark
Posts: 6
Joined: 1 year ago

#1: Post by robotshark »

Had my Lelit Elizabeth for about a year. I've noticed that the pressure during a shot will change during the shot - e.g. it will rise to 9 bar, and then bounce around +/- 1 or so until the shot is over. This also happens when testing with a blank disc (see attached video). You can even hear the pump (?) get softer when the pressure goes down.

Looking at examples online of folks using the blank disc I never saw a similar issue, so something seems up here. Has anyone encountered this before?

Video of the issue, with a blank disc and a 'shot' with no preinfusion.

JRising
Team HB
Posts: 3731
Joined: 5 years ago

#2: Post by JRising »

Probably one of these situations where the pump is visibly dropping pressure along with the on/off cycling of the brew boiler's element. 1 Bar is pretty serious fluctuation. You could try it in different outlets, to try to determine if the resistance is mostly in the machine or in the wiring to the kitchen's outlet. If it's still 1 Bar fluctuation in a dedicated outlet near your electrical service, then I would be a little concerned that the power switch on the machine may be building up carbon and inserting more than 0.4 ohms resistance.
If you aren't comfortable working on live machines, please don't. If it were in my hands I'd start by monitoring voltage across the pump as the fluctuations occur, if it's a significant drop there occurring with the element, then I'd measure voltage across the power switch as it occurs... Of course, if voltage across the entire machine is less than 112VAC and dropping further below that, then you'll want to fix the house.

RTM
Posts: 92
Joined: 1 year ago

#3: Post by RTM »

I would guess that this could be from the OPV valve needing some TLC and being sticky/ or scaly

DaveC
Posts: 1777
Joined: 17 years ago

#4: Post by DaveC replying to RTM »

Agreed

robotshark (original poster)
Posts: 6
Joined: 1 year ago

#5: Post by robotshark (original poster) »

I will give that a try - I saw some instructions in this thread - https://coffeetime.freeflarum.com/d/116 ... sistent/30 about cleaning the OPV - are those what you all think I should try?

DaveC
Posts: 1777
Joined: 17 years ago

#6: Post by DaveC »

Yes, give it a try.

coyote-1
Posts: 517
Joined: 2 years ago

#7: Post by coyote-1 »

I'll offer a different take: what you're seeing is not an issue. At all. I see a very similar pulse in my ViaVenezia, which has a brand new vibe pump. And it does not correlate to anything occurring with the heater. Note that I use a flow control dimmer, and the fluctuations don't occur when I'm pre-infusing. They only occur at pressures above 8 bar or so.

But back to my first sentence.... this little pulse is not going to make a good shot bad. The quest for perfect pressure is like the quest for a perfect puck. It is ancillary at best to the result in the cup. Only if your shots don't taste good should you concern yourself about it.