New Rocket Giotto V pump pulsing/fluctuating? - Page 2

Equipment doesn't work? Troubleshooting? If you're handy, members can help.
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erics
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#11: Post by erics »

You are being given incorrect responses from the retail dealer (I assume this machine was purchased new) and Rocket. That sound at ~4.0 bar is NOT normal but the pressure fluctuations MAY be normal if you were doing the video when the machine was first warming up. You do have a PID equipped machine ?

Image

I believe the pic above duplicates your machine. Item 1 is a ball valve, item 2 is a secondary "OPV" (setting is unknown), item 3 is a check valve, and item 4 is the primary OPV. The ball valve should be open when operating the machine.

With the machine on for about 45 minutes and a blank basket in the portafilter, close the ball valve and start the pump. Adjust the primary OPV such that the brew pressure reads ~ 9.0 bar. Repeat a second time to ensure consistency. Now open the ball valve and see if the unusual sound (at ~4.0 bar) and the pressure fluctuations go away.
Skål,

Eric S.
http://users.rcn.com/erics/
E-mail: erics at rcn dot com

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kolu

#12: Post by kolu »

The OPV #2 is for the pump pressure, OPV #4 (after check valve - in the HX circuit) is safety valve for HX.
OPV #2 is usually set around 10 Bar on all Rocket machines with Ulka pumps.
OPV #4 is set by a manufacturer (OEM) around 12 Bar.

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erics
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#13: Post by erics »

My comments were based on info I posted in this thread: Brew pressure reading of blind basket vs. Scace thermofilter

My memory is not as good as it once was as I was WRONG then and WRONG now.
Skål,

Eric S.
http://users.rcn.com/erics/
E-mail: erics at rcn dot com

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kolu

#14: Post by kolu »

your picture, Eric, actually comes extremely handy as I work daily on these machines (at official Rocket machines distributor here) but I'm too lazy to look for pictures of internals and most probably have only pictures of the heavy abused or wildly leaking ones.
so I tried to clarify the situation a bit.
anyway - closing the ball valve might give us bit more insight in finding the problem as it might indicate pump-OPV related issues.

but it's interesting as I don't remember seeing a Rocket behaving in a such way here.