Dripping Expansion Valve

chas · Post by **chas** » Thu Jun 03, 2004 7:16 pm

I have been having trouble with a slight drip from the expansion valve since I received the S1. It's not a big deal - about 12-16oz per day. Of course it might be a big deal if you left the machine on and went on a business trip for a few days.

After adjusting it, cleaning, inspecting and readjusting it there was no change. The strange thing is that even when the PF pressure is set to 12-13 bars (just before it's set to open up) it does not drip at all. It just drips periodically when sitting idle when there should be little pressure on the valve. I received a replacement valve from Chris Coffee today. Changing it out is very easy. That wasn't it. It's till dripping with the new one.

This has both Chris and I scratching our heads. I think Chris plans to talk to the engineers at LaSpaziale about it next. While the drip is minor it just makes no sense that it drips when it does and not when it is under pressure. Stay tuned for updates!

Post by **barjohn** » Fri Jun 04, 2004 6:54 pm

Since I reduced the water pressure with a regulator and a check valve I only get the drip when I first turn the unit on (not when it is sitting idle green light blinking). After the first use it quits. If I leave the unit on it does not drip. Before, it dripped when off and not when on.

If yours is dripping when the unit is off, I can tell you that it is related to the street water pressure. To get it to stop I furst had to bring the pressure down to 22 psi. I am currently sitting at 25 psi. Schomer claims he sets his units to 15 psi. Have you tried reducing your water pressure to the unit?

My theory is as follows:
In the off state all three solenoids, A, B, and C are closed. The heated water in the group boiler is at very near boiling temperature and exerting pressure back through the feed line from the flow meter and back to the overpressure valve. The reason that the boiler pressure is so high is that you have no direct way to relieve the boiler pressure. It is pressuerized by the water pump. If the circuit that turns off the pump does not turn it off when the shot is complete or you press the button to stop the shot but a few 100 milliseconds later so that it can refill the boiler while the three way valve is emptying the pressure from the PF, then the boiler may be up to 8-10 bar, plus the pressure from the heated water. The combined pressure from the group boiler and the street water may be sufficient to cause the valve to open just a fraction. A check valve between the group boiler and the flow meter might stop the effect. Reducing the street water pressure definitely helped.

Just my theory.

chas · Post by **chas** » Fri Jun 04, 2004 8:43 pm

I'm glad you posted this note. I actually received a pressure regulator from Chris about 10 days ago. When I installed it - even with pressure set to its highest - hardly anything came out of the hose and the nasty noise from the pump made it obvious it was starving for water.

I guess I wasn't in the mood for troubleshooting and your post caught me in the mood so I revisited things. After complete disassembly of the regulator the problem revealed itself.

Whoever installed the 3/8" JG fitting on the outlet side of the regulator screwed it is so tight it butted up against a piece of plastic inside the regulator blocking the flow.

It's fixed now and set to about 25lbs (20psi when it is pumping) so I'll see what happens overnight. Generally from now until 7-8AM I'll get 5oz of drip for a 24-hour rate of about 12oz assuming the unit is completely idle. I figure with the addditional drippage when the unit cycle maybe 16oz a day on average.

Side Note: A small puddle has formed while I've been writing this. However, I'll check the amount in the morning to see if it is reduced and perhaps drop the pressure a little lower just for grins.

Post by **barjohn** » Sat Jun 05, 2004 1:49 pm

I would try going down until it stops. That is what I did the first time. You should be ok to 15 psi; however, you will have to readjust your PF pressure as it will drop it. More than simple theory can explain since it is supposed to be cumulative. I went down to 20 psi and slowly worked it back up.

chas · Post by **chas** » Sun Jun 06, 2004 9:20 pm

Success! You were right. I dropped the pressure another 5 psi and now I am high and dry. Now the inlet water pressure is 19 psi when idle and 15 psi when the pump is running.

I recently dropped and screwed up my PF pressure gauge but a replacement arrives tomorrow. Thanks for the heads up that I'll need to readjust the group pressure. I wouldn't have thought of that.

Post by **barjohn** » Thu Jun 10, 2004 10:29 am

Mine recently started dripping again. I dropped the pressure back to 22 psi and it stopped. Did you ever hear from Chris on what they have found is the problem. It would seem that the unit should be able to operate with higher input water pressure.

chas · Post by **chas** » Thu Jun 10, 2004 7:50 pm

Even with a new expansion valve and the pressure as low as 15psi, mine still drips. Chris said he was going to discuss it with LaSpaziale. I've sent him a few e-mails the week and have gotten no replies. I'm guessing he's out of town on a business trip.

chas · Post by **chas** » Tue Jun 29, 2004 9:39 pm

A few weeks back after replacing my expansion valve and seeing no change it the drip rate, Chris said he would keep an eye on the S1's he had in stock. Here's what he found:

I just wanted to drop you a line about the drip.

I just got a new shipment of La Spaziale S1 machines in. I have been testing the amount of water that drips from the expansion valve. I have found that on all the machines I check they have a drip that amounts to 8 ounces over a 24 hour period, which apparently seems to be normal. I have not been able to get an answer from anyone at La Spaziale to explain to me why it drips at all. Not due to unwillingness but because of the language thing. I have found that the amount of water that drips increases as the line pressure increase above 40 P.S.I. as well.

I am going to check out some of the other commercial machines in my display room to see if they too drip. They are all connected to a drain so there is a possibility that i just never noticed it. I will keep you informed.

chas · Post by **chas** » Fri Aug 27, 2004 8:37 am

I think I noted this in the quieting thread several weeks back. After beating my head against the wall in tryiing to get the dripping expansion valve to stop by multiple disassemblies, adjustments, cleanings, and finally replacement with no luck, I had resigned myself to it just being a design issue. Chris even noted that a number of his machines - S1 and others did the same thing.

However, in the quieting thread I noted that I had fully "insulated" the inside of my S1 with Dynamat Extreme. The next morning I noticed that my drip tray was dry - no more 8-12oz a day of drippage from the expansion valve.

Two months later I am still high and dry. I did absolutely nothing except remove the side and rear panels and apply the Dynamat. The only theory I have now is that the additional vibration in the machine when running was vibrating the expansion valve and causing seepage. The expansion valve innerds are just a spring with a rubber washer on the end, so it seems feasible. It could all still be a fantastic coincidence. At any rate I will not tempt fate and pop the covers again until there is a reason to do so;>

Post by **barjohn** » Mon Aug 30, 2004 1:27 pm

I too installed Dynomat. However, it had no effect on my expansion valve's drip rate. Mine only drips when first turned on and then stops.

chas · Post by **chas** » Fri Sep 03, 2004 7:43 am

Mine may still drip like yours when first turned on. It's been on non-stop except for maybe twice during the summer while I was out of town and I haven't paid much attention to warming up drippage on those two occasions. But the constant dripping of about 12oz per day has definitely ceased.

Post by **wgaggl** » Fri Sep 10, 2004 5:17 pm

Mine drips when first turned on, and sometimes in between, when the machine gets back to temperature after pulling several consecutive shots.

Post by **Barry** » Sat Dec 18, 2004 1:01 pm

Installed the pressure regulator this morning. The only time the pressure actually appears to be stable is when the machine is in standbye mode. I suspect this has to do with changes in pressure as the group head boiler pressure is increasing. If I set the pressure to 15 PSI while the unit is in standbye, the pressure goes up as high as 60 PSI when the boiler is heating. I have the regulator just prior to the S1 after the filters. Are people setting the pressure regulator once the unit is up to temp. or while it is in standbye? I am off to get a check valve as well.

Regards,
Barry

Post by **NewEnglandCliff** » Thu Feb 03, 2005 5:38 pm

I serendipitously avoided this dripping problem by plumbing mine with bottled water and a Flojet pump. When the S1 is in standby, the Flojet remains off resulting in no water pressure at all to the machine. It's very easy to do and has a few other benefits, as well. You can locate your machine just about anywhere you want, and you know your using good water. Maybe you should look into it.

chas · Post by **chas** » Thu Feb 03, 2005 6:22 pm

NEC: Is there a problem with the URL you are using to point to your photo/avatar? All I am seeing is the dreaded box with the red "X" in it.

Post by **NewEnglandCliff** » Thu Feb 03, 2005 7:53 pm

I've fixed the problem. Thanks.

Post by **Barry** » Tue Aug 16, 2005 9:19 am

Add me to the club....for nine months I have never experienced any dripping from the expansion valve. Last night I turned the machine on and thought I heard the sound of dripping. Sure enough, the expansion valve was dripping at a rate of about 1 drop every 30 seconds. Equally as bizzare, the drip appears to slow/stop once both boilers are up to pressure. Considering that it does not appear anyone has definitively figured out what the problem is, it appears the best course of action is to ignore it. Just out of curiousity, has anyone checked back with Chris to see if they have figured out what the problem is? My supply regulator is set to about 22 PSI.

Post by **admin** » Tue Aug 16, 2005 11:32 am

Chris says the ones in his shop do this and the ones at the Laspaziale factory do this so that's the way it is. Mine has always dripped while it is warming up and for a minute or two after pulling a shot, but it also used to drip every time the boilers cycled. This is what bothered me. I could empty the drip pan after my last shot of the day and by the next morning there would be 6-8 oz of water. This meant that you could never go away for more than a day and leave the machine on without worrying about a flood.

I tried adjusting and readjusting everything. Chris even sent me a new valve. Nothing... Then one day I needed to remove the covers to get inside and fiddle with something and I did not even go near the expansion valve. Since that day it has not dripped once when the boilers cycle.

Post by **Barry** » Tue Aug 16, 2005 2:12 pm

What I find somewhat frustrating is that this is considered "normal". If my car constantly dripped oil and someone told me they all did that I would definetly purchase another brand. Probably not a fair analogy but who produces a product with a known flaw and says it is normal....oh wait a minute...Microsoft calls it a feature!

Post by **hlsheppard** » Tue Sep 20, 2005 8:58 pm

My S1 didn't drip for a whole week and now drips as it's warming up and VERY slightly thereafter (prob. when boilers are cycling).

Nothing too annoying - but I'm wondering if *I* caused the drip by backflushing?

Post by **Niko** » Mon Dec 25, 2006 1:22 am

Too much backflushing with Cafiza can make matters worse. It can make the valve stick open and drip even more.

I'm the master of "finding out the hard way".
I did the opposite with this one, I listened to Spaziale's advice on "not" backflushing and this wreaked havoc on my machine.

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