Posted Sat May 19, 2012, 10:11am Subject: Re: pressure profiling with vibe pump
My dimmer is rated at 600 watts and I have no problem with the range. I get useful pump power at every setting - though it is extremely low flow at the lowest setting there is still water coming out the group head and I can still hear the pump vibrating (very quietly).
First question (sorry if you've already answered this) - do you have a 3-way solenoid valve on your machine?
On my gaggia (not sure how your boiler works) there is a stand pipe inside the boiler. I like to set my dimmer to full power, then push BOTH the steam switch and the brew switch. On the Gaggia (with a 3-way) this will close the 3-way so nothing comes out the group head and the pump will fill the boiler to the top (above the standpipe inside) so I know the boiler is really full. The reason I suggest this, if your boiler is only half full - nothing will come out until the pump fills the boiler to a level higher than the top of the standpipe. So you want the boiler filled before you start a shot with the pump turned to a really low setting.
ALso .. if your machine is one without the 3-way valve, you will get very different results because you are fighting the resistance of the spring loaded group valve (you have to build up 4-6 bars before you can even push that spring back to let anything out the group).
Posted Sat May 19, 2012, 10:24am Subject: Re: pressure profiling with vibe pump
hey andy, the Saeco Via Venezia that i have does not have a 3-way valve. This would explain why im not getting any water until i raise up the voltage up to a pretty high level. Do you think changing out to a higher watt capable dimmer or higher watt pump would have any effect? I'm gonna look into that spring you're talking about. Maybe i can adjust or modify it to allow water through at a lower pressure.
I'm currently sliding the dimmer up to about 75% to get water to flow and then backing off slightly to get preinfusion started. When i see the drops start coming down, i'll go full power for a few seconds and then back off again to as low as i can go without stalling the water for the rest of the pull. I've been pulling ristrettos with this and getting what i think is more body in the cup. I really wanna give this a try a bright single origin to see if i can get all the fruit without all the harshness.
Posted Sat May 19, 2012, 10:24am Subject: Re: pressure profiling with vibe pump
AndyPanda Said:
My dimmer is rated at 600 watts and I have no problem with the range. I get useful pump power at every setting - though it is extremely low flow at the lowest setting there is still water coming out the group head and I can still hear the pump vibrating (very quietly).
First question (sorry if you've already answered this) - do you have a 3-way solenoid valve on your machine?
On my gaggia (not sure how your boiler works) there is a stand pipe inside the boiler. I like to set my dimmer to full power, then push BOTH the steam switch and the brew switch. On the Gaggia (with a 3-way) this will close the 3-way so nothing comes out the group head and the pump will fill the boiler to the top (above the standpipe inside) so I know the boiler is really full. The reason I suggest this, if your boiler is only half full - nothing will come out until the pump fills the boiler to a level higher than the top of the standpipe. So you want the boiler filled before you start a shot with the pump turned to a really low setting.
ALso .. if your machine is one without the 3-way valve, you will get very different results because you are fighting the resistance of the spring loaded group valve (you have to build up 4-6 bars before you can even push that spring back to let anything out the group).
Andy, my Saeco Aroma does not have a 3-way solenoid valve, but since it is designed to be used with a pressurized portafilter, it is pushing far too much pressure to the group when I am using my nonpressurized pf. I may add a solenoid at a later time but this will be my first attempt to lower group pressure. Also, I am not positive that my theory on wattage rating on the dimmers is correct. I just thought I would give this a try and see what kind of results I get. I should have the dimmer Wednesday and hope to get it in the machine by that evening. I am hoping for good results but basically I am flying blind at this point.
Posted Sat May 19, 2012, 10:33am Subject: Re: pressure profiling with vibe pump
in my machine, it looks like the spring you're talking about that needs to be compressed before letting any water out is the mushroom/poppet valve that is connected to the bottom of the boiler tube. Looks like this is a low price item Click Here (espressocare.com)
it might be worth it for me to modify this spring or find a spring that will open the valve at a lower pressure.
Posted Sat May 19, 2012, 10:51am Subject: Re: pressure profiling with vibe pump
frank828 Said:
in my machine, it looks like the spring you're talking about that needs to be compressed before letting any water out is the mushroom/poppet valve that is connected to the bottom of the boiler tube. Looks like this is a low price item Click Here (espressocare.com)
it might be worth it for me to modify this spring or find a spring that will open the valve at a lower pressure.
Maybe you could take the spring down to a local hardware store and try to match it up with one. Then you could modify the new one and save the original in the event you want to return the machine to stock condition.
Posted Sat May 19, 2012, 11:01am Subject: Re: pressure profiling with vibe pump
wsikes Said:
Maybe you could take the spring down to a local hardware store and try to match it up with one. Then you could modify the new one and save the original in the event you want to return the machine to stock condition.
Posted Sat May 19, 2012, 11:02am Subject: Re: pressure profiling with vibe pump
i may just try to buy a couple of these springs and clip a loop or two and stretch it. if this doesnt work well, i'll probably need to find this hardware store you speak of :P (living in metro Los angeles, you rarely see specialty hardware stores).
*off to do more google searching on local sources of springs*
bill, nope. that is the overpressure valve that is connected to my water pump. the spring i'm talking about is below the boiler and before the shower screen. there needs to be a certain amount of pressure before it will compress and then release water.
Posted Sat May 19, 2012, 11:19am Subject: Re: pressure profiling with vibe pump
frank828 Said:
bill, nope. that is the overpressure valve that is connected to my water pump. the spring i'm talking about is below the boiler and before the shower screen. there needs to be a certain amount of pressure before it will compress and then release water.
hmm...i'm not at home so i can actually do it right now but after examining the diagram, it looks to be accessible once you remove the shower screen. it looks like the shower screen screw is screwed into the poppet/mushroom valve holder. once the screen and maybe the gasket comes out, i should have access to the valve holder. it looks like there is a flat head notch on the valve holder that then threads into the boiler tube at the bottom of the boiler.
while i'm down there, i may replace the shower screen with this older style shower screen that should allow for better flow through the screen. http://www.espressoparts.com/SAE_1 . I currently have the newer ESE compatible screen that concentrates the water flow towards the middle of the screen.
Symbols: = New Posts since your last visit = No New Posts since last visit = Newest post
Forum Rules: No profanity, illegal acts or personal attacks will be tolerated in these discussion boards. No commercial posting of any nature will be tolerated; only private sales by private individuals, in the "Buy and Sell" forum. No cross posting allowed - do not post your topic to more than one forum, nor repost a topic to the same forum. Who Can Read The Forum? Anyone can read posts in these discussion boards. Who Can Post New Topics? Any registered CoffeeGeek member can post new topics. Who Can Post Replies? Any registered CoffeeGeek member can post replies. Can Photos be posted? Anyone can post photos in their new topics or replies. Who can change or delete posts? Any CoffeeGeek member can edit their own posts. Only moderators can delete posts. Probationary Period: If you are a new signup for CoffeeGeek, you cannot promote, endorse, criticise or otherwise post an unsolicited endorsement for any company, product or service in your first five postings.
= No New Posts since last visit 