Can I adjust the expansion valve of Rocket Appartamento to limit brew pressure at 9-10 bar?

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RYUKO
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#1: Post by RYUKO »

Can i adjust the expansion valve (14# in the picture) of APPARTAMENTO to limit brew pressure at 9-10 bar?

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cafeIKE
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#2: Post by cafeIKE »

Probably.
What is current blind basket gauge pressure?
The group has a gicleur, so you probably need +1 to +1½ bar on the gauge against a blind basket.

DaveC
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#3: Post by DaveC »

You can indeed adjust the expansion valve of the Rocket to 9 or 10 bar. Don't try to go too much lower than 8 though.

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homeburrero
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#4: Post by homeburrero »

Yes. The Appartamento is straightforward compared to some other Rockets and has that single expansion/OPV valve (the one that you circled) where you can adjust your brew pressure. Since you have no gauge on the machine you may need to rig one on your portafilter, and if you rig a simple system where no water flows out of the portafilter then you can adjust it so that the max pressure on that gauge hits 9.5 or 10 bar. With your vibe pump that should give you roughly 9 bar max on a typical flowing shot.

P.S. (edit addition)
For people with a presta bicycle tire gauge, there is a very low cost kludge: Zero cost adapter for portafilter pressure gauge

Pat
nínádiishʼnahgo gohwééh náshdlį́į́h

RYUKO (original poster)
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#5: Post by RYUKO (original poster) »

I was going to build a brew pressure gauge on GROUP, :shock: a portafilter pressure gauge,good thinking

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cafeIKE
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#6: Post by cafeIKE »

Since you have an e61, use the bolt hole and eric's adapter. Any gauge will work. Buy a hand-full of the copper crush washers if you intend R&R a lot



Original topic Digital Pressure Adapter which has list of parts. Some links maybe DoA

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homeburrero
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#7: Post by homeburrero »

^^^^ good idea. If you were to upgrade to a flow profiling kit it would come with a brew pressure gauge there, but that would cost a bit. And in my opinion once you've gotten your OPV adjusted you're best off putting in the EricS thermometer there and learning to use the machine with the standard E-61 flow characteristics. Then someday, maybe, consider going down the flow profile rabbit hole after you've mastered the standard HX/E-61. (I've been using an HX and E-61 with the EricS thermometer for years and am still not tempted to change to a flow control mod.)
Pat
nínádiishʼnahgo gohwééh náshdlį́į́h

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cafeIKE
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#8: Post by cafeIKE »

homeburrero wrote:(I've been using an HX and E-61 with the EricS thermometer for years and am still not tempted to change to a flow control mod.)
Ditto.

My flow control is my grinder, scale, basket and coffee.

beeb
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#9: Post by beeb »

Hi there! I adjusted my expansion valve on the Appartamento to reach 8 bars (a little more) at the group head, but now there is a tiny bit of dripping/leaking happening through the thread I unscrewed to lower the pressure (part circled in red above). Can I remove that threaded nut/part completely and add some teflon tape on the thread to seal it?

DaveC
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#10: Post by DaveC replying to beeb »

I'm guessing your machine isn't brand new....so remove the adjuster completely and check/Lube/replace the O ring..in the photos in my article below, yours looks like the one on the right. Teflon tape isn't the right way

http://coffeetime.wdfiles.com/local--fi ... _Valve.pdf

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