Losing Brew Pressure!

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JerDGold
Latte
Posts: 16
Joined: Thu Dec 11, 2014 11:19 pm

Losing Brew Pressure!

Post by JerDGold » Fri Jan 30, 2015 12:10 pm

Started a few weeks ago, but only happened very infrequently. I chalked it up to a choked machine and assumed I was somehow losing pressure through the solenoid valve. In hindsight, I'm realizing that isn't possible anyways (or indicative of a separate problem). Fast forward to this morning.

Every shot I pulled followed this pattern:

1) Pressure builds to 9-10 bars.
2) Pulls for a second or two.
3) Usually loud vibe pump goes MUCH quieter and pressure gauge begins to fall.
4) Shot continues to pull as pressure falls to about 4 bars.

The most indicative and readily noticeable symptom for me, other than the loss in pressure, is the sounds of the pump. It goes super quiet, almost like a rotary. A low a hum. Shots pulled with this problem are super sour and acidic. I'm going to try and pull a few right now and see what happens...but what should I look for when I open this bad boy up?

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chas
Vivaldi Dreamer
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Re: Losing Brew Pressure!

Post by chas » Fri Jan 30, 2015 1:16 pm

The first thing you should try if you have one of these in tank softener cartridges is to take it out. They seem to cause many of these type of issues.
Chas
LM GS/3 & LaSpaziale Dream v 1.23 (US 120V)
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goodboyr
God Shot
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Joined: Thu Jan 10, 2013 10:05 pm
Location: Canada

Re: Losing Brew Pressure!

Post by goodboyr » Fri Jan 30, 2015 7:26 pm

Isn't this when the auto fill for the steam boiler comes on at the same time as a shot? The pump thus has two discharge paths. Are you making milk based drinks? Try steaming after the shot instead of during or before.
Bob
La Spaziale Dream and Baratza Sette 270W

reefkeep
Americano
Posts: 6
Joined: Sat May 25, 2013 8:35 am

Re: Losing Brew Pressure!

Post by reefkeep » Fri Jan 01, 2016 8:52 am

I'm having this same issue


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Atomic
Americano
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Joined: Thu May 15, 2014 3:38 pm

Re: Losing Brew Pressure!

Post by Atomic » Sun Mar 10, 2019 1:12 am

Any updates on this?

I've had this happen a few random times on my Dream T. I removed the water filter years ago. Randomly part way through the brew, say @ 10-15 seconds the pressure drops and the pump becomes much quieter. I stop the shots, checked with the blind basket and it holds 9.5 bar just fine again. Maybe a few weeks go by and it does the same thing again. I checked the tank level and it was over half full, so not drawing air etc.
Running latest v1.24. 15a mode E. I steam milk post brew.
Pump failing? Should I disassemble the pump and clean it?
Thanks

reefkeep
Americano
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Joined: Sat May 25, 2013 8:35 am

Re: Losing Brew Pressure!

Post by reefkeep » Sun Mar 10, 2019 7:13 am

I have the same problem

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Atomic
Americano
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Joined: Thu May 15, 2014 3:38 pm

Re: Losing Brew Pressure!

Post by Atomic » Wed Apr 10, 2019 1:46 am

Update on my end; loosing brew pressure continued to randomly occur until this weekend where it would ramp up and them go back down to about 2-bar with the blind basket continuously.

Checked that it was getting 120v and then pulled the pump and dissembled it (super easy, 2 screws, twist and pull the cylinder and voila, the plastic insert on the outlet side retaining the spring needs a pair of pointy tweezers to insert and reverse screw out) There was a bit of corrosion and flakes around the mushroom seal so i guess it wasn't seating properly and the rubber bits in general seemed a bit harder. Put it back together, it primed and pulled water to the group but it still didn't sound right and wouldn't build pressure. New pump was in stock at my local espresso repair shop...definitely more than could be had online but I didn't want to wait. Ulka EX5 120v 41W (old one was a 2010 production)

The new pump wouldn't prime! Tried a kitchen squeeze bottle and nothing. Pulled it apart, found the mushroom to be seated. Now it primed easy. Back up and running....hopefully it lasts a few more years.

Really too bad there isn't an easy supply for a rebuild kit instead of buying the coil too....

One of my local vendors said they carried OLAB pumps to replace the ULKA and seem to think they last longer. I didn't feel like trying something new now but if this one fails again I might consider.

So if you are randomly loosing brew pressure and the pump is making a much lighter hum, it might be a sign that you should order a replacement so it is on hand if you want to avoid downtime.

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