Losing Brew Pressure!

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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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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.
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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.
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Re: Losing Brew Pressure!

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

I'm having this same issue

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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?

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Re: Losing Brew Pressure!

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

I have the same problem

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