Problem with Linea brew pressure! what to do?

[alexanderruas]

Even if my Linea 1 gr EE has been on for hours the brew pressure gage will keep dropping down to 0. when I click the "brew/on" button it climbs up to 9.1 after about 4 seconds. then it stays there during the shot and also after for a half a minute. then it slowly drops down to 0 again.


even though it's been on all day


while pulling shot

I have been told that it seems my expansion valve is faulty and does not let out water through the rubber/plastic valve but instead lets it out by dripping from behind. I have tightened and loosened the expansion valve but no difference.

or do you guys have any other ideas?

]
is it broke?

what do do?

thanks,

alexander

[SteveM]

To me it looks as if the boiler gauge reads about 1.3 Bar, which is a bit low, but OK.
It looks like the brew pressure is the one that drops to zero when inactive, and then goes to a bit over 9 bar when brewing, which again is normal.

[alexanderruas]

oops! you are correct. it's the brew pressure I am having trouble with.

but most Lineas I have observed the brew pressure doesn't drop down to 0 when inactive. my machine did not use to do this. it also now takes a looooong 4 seconds for it to reach the 9-ish bars when brewing.
I solve this by running the water during the pre-brew heating of the group for about 5 seconds and then lock in the PF and pull my shot. this works and otherwise the pressure & temp are very stable but I still want to know why this is happening.

thanks,

a

To me it looks as if the boiler gauge reads about 1.3 Bar, which is a bit low, but OK.
It looks like the brew pressure is the one that drops to zero when inactive, and then goes to a bit over 9 bar when brewing, which again is normal.

[barry]

Is this machine fed from "city water" or from a bottle?

[alexanderruas]

bottle. 25 liter.

[barry]

bottle. 25 liter.

my guess is your inlet check valve has failed, and the pressure is venting back into the bottle.

[gscace]

bottle. 25 liter.

I agree with Barry. Also, you might look at your pressure relief valve (the one that drains into the drain tray) to look for dripping after brewing as the pressure drops. Typically the brew boiler pressure should increase over a couple of minutes after brewing is completed because the cold feedwater expands in the boiler with no place to go. Once the pressure hits 12 bars, the expansion valve opens and a little bit exits into the drain tray. If it drips while pressure goes down, disassemble it, clean out the offending crap and reassemble. You'll need to re-adjust it to open at 12 bars. You mentioned that you had fooled with the position of the valve, which influences its cracking pressure. Make sure that it is set for 12 bars cracking pressure. If it is set substantially higher you risk failure of the brew boiler, which will be unpleasant, both physically and financially.

-Greg

[cannonfodder]

If it is set substantially higher you risk failure of the brew boiler, which will be unpleasant, both physically and financially.

-Greg

That has to be the most understated way of saying your boiler will explode that I have ever seen.

[barry]

That has to be the most understated way of saying your boiler will explode that I have ever seen.

more likely to spring a leak than fail catastrophically.

9 bar water goes a looooooooooong way across a room.

[alexanderruas]

thanks guys for all the input.
I am in no way risking going over 12 bar. if anything it's the opposite. I have loosened the valve just in case. plus the machine takes it's time getting up to 9 bar. if it started at 9 and tended to climb & stay towards the 12 mark I would get worried and shut the machine off!

thanks again!

a

[shadowfax]

9 bar water goes a looooooooooong way across a room.

... probably not the best feeling on your person if you happen to be standing in the path of the spray ...

[stefano65]

do you have a one way valve installed on the output of the pump?

[alexanderruas]

do you have a one way valve installed on the output of the pump?

how can I tell? see photo below. can you tell?

[darrensandford]

If it's the same as mine, the longer stalk on the connection on the left of the pump is a one-way check valve - you have one fitted.

[Paul]

one way valve on the pump is the stainless steel fitting on the output side. The braided hose going to your machine is attached to the other end.

[stefano65]

you need some water pressure in the unit
bottle fed is not enough

[alexanderruas]

you need some water pressure in the unit
bottle fed is not enough

thanks guys! feels good to know and always good to learn something new!!

alexander