Announcement
Collapse
No announcement yet.
Measuring Group Head Pressure on a HX machine
Collapse
X
-
There will be a small difference between the pressure measured with flow and without flow, restrictions/bends in the path between the opv/bypass and the group will cause pressure drops only when theres flow past themOriginally posted by brendogs View PostWhy do you have a valve on there? Any reason or just needed those fittings to complete the job?
I'll take a photo of mine which I made a few days ago.
Nice work, but you got the same gauge at reece for under $4.7? evilbay got me again
- Flag
Leave a comment:
-
-
Why do you have a valve on there? Any reason or just needed those fittings to complete the job?
I'll take a photo of mine which I made a few days ago.
- Flag
Leave a comment:
-
I think with pressure taken care of temperature can be tuned reasonably easily by taste... i.e. I dont have a temp probe
- Flag
Leave a comment:
-
Arrrghhh ! ..Frankengauge gage !
Are you sure you couldnt fit a temp probe in there somewhere ?
- Flag
Leave a comment:
-
Would you believe the only piece I needed to put this monstrosity together from parts I had already was a 1/4" nipple?

- Flag
Leave a comment:
-
Measuring the Bypass Volume is really nothing better than an indicator, you know. Pretty rough...
You'd have to allow an error margin of +/- 1.25Bar for a nominal bypass volume. Still far better to use a decent pressure gauge/needle valve setup (or similar). I'd take up the offer above or contact Greg Pullman to use his rental hardware.
Mal.
- Flag
Leave a comment:
-
But without a gauge, take the return hose out of the tank (The hose with nothing on the end), and measure the outflow with a blind basket.
The EP5 pump graph is below, 100% of the flow will be going through the return hose, so check how many ml/min comes out and find the range it falls in on the graph, dotted lines represent the tolerance/variation that is possible, so if you measured 260ml/min like in the graph, it could be anywhere between 7 and 10 bar. This does not take into account any pressure losses happening between the OPV and the group, for that you need a portafilter gauge with appropriate flow.

And take it easy on the pump, the specs say it can run for 2 minutes on with 1 minute breaks.
- Flag
Leave a comment:
-
I can lend you a portafilter+gauge if you can pickup/dropoff in the city, but I dont have a valve to regulate the allowed flow, so you just loosen up the fittings until 60ml drips out over 30 seconds. Send me a PM
- Flag
Leave a comment:
-
Measuring Group Head Pressure on a HX machine
Hi All,
I recently upgraded to the beasty Rancilio S24, which is just a joy to run.
Quick question though, would anyone know how to measure the group head pressure (as opposed to the boiler pressure, which doesnt seem to move from the 1.3-1.5 bar mark while in use)? I was thinking of setting the OPV to 9 bar at the group, but don't have any fancy brew pressure PF to do so. Is there any other way to set it up like that??
Cheers,
Aaron

Leave a comment: