Low Pump Pressure Error

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CoffeeHound

Low Pump Pressure Error

Post by CoffeeHound »

Anyone having Low Pump Pressure error messages? I've had about 7 in the past month, seem to be getting more frequent. I think I saw a drop in pressure around 8 or 10 seconds then it rose again without tripping the error message--thoughts?
etout00

Re: Low Pump Pressure Error

Post by etout00 »

I have received the l'ow pump pressure' message too for no apparent reason while pulling a shot...it happened on a couple occasions and went back to normal once I ended the shot.

I replaced my Dream with a GS/3 MP though....
goodboyr
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Re: Low Pump Pressure Error

Post by goodboyr »

Just got one too. Pressure dropped to about 4 bars and alarm came on. Then back to normal. I did a few back flushes and have pulled a few shots since, but all normal now. Weird.
Bob
La Spaziale Dream and Baratza Sette 270W
CoffeeHound

Re: Low Pump Pressure Error

Post by CoffeeHound »

I replaced my Dream with a GS/3 MP though.... yeah, that would do it :-P

It seems to be a sticky valve. I had an error three days in a row when I posted and have been clear water backflushing once a day since and no errors. I had done a detergent backflush and now I'm wondering if my phosphate free cleaner is up to the task--though I think I had a couple of errors before I used it. Guess I'm a daily backflush convert now (I had read pros and cons).
goodboyr
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Location: Canada

Re: Low Pump Pressure Error

Post by goodboyr »

Ok. Just had this happen again. Pressure went to 4 bar about halfway through the shot and the alarm sounded. Stayed on till the end of the shot at 30 seconds. I then did another two shots without any backflushing. Just my usual rinse and clean routine, and everything was fine, no alarm, steady 9 bar pressure. So, whatever this is, it is very intermittent. I am backflushing with water every few days. I've only done one detergent backflush routine after a month of use, that was about a week ago.
Bob
La Spaziale Dream and Baratza Sette 270W
CoffeeHound

Re: Low Pump Pressure Error

Post by CoffeeHound »

Had another one yesterday, so that's one in about 10 days--much improved from three days in a row when I started the thread. I am using detergent every two weeks with the last (second) time being Monday this week. The clear water backflush is obviously helping; I've switched to backflushing before pulling shots in the morning and hope that ends it.
CoffeeHound

Re: Low Pump Pressure Error

Post by CoffeeHound »

Just a follow up: I still receive these errors sporadically. Spoke with a tech at Chris Coffee and he thinks it's my house line pressure, I have a regulator but have seen some strange numbers from time to time. I'll try to dive under the sink next time I get the error and see what the regulator gauge is reporting.
goodboyr
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Location: Canada

Re: Low Pump Pressure Error

Post by goodboyr »

I have continued to get the odd seemingly random low pump pressure error, so I decided to test some theories, and I believe I have found the issue. This error occurs when there is a simultaneous demand to fill the steam boiler (based on the steam boiler level) and you are pulling a shot. If you draw off some hot water via the tap (mine is programmed for 8 oz), the autofill will come on for the steam boiler a few seconds after the end of the water coming out. If you also happen to be pulling a shot when the boiler is refilling, the low pump pressure error will occur. You don't notice the autofill during a shot, because the pump is already running and it seems to occur randomly because the steam boiler autofill only happens occasionally on its own, and it would have to be coincident with a shot being pulled. Probably because the gliceur for the steam boiler brings the pressure in the line down to 4 bar, and this propagates throughout the system. My suggestion is for a software fix that inhibits the steam boiler from auto refill while a shot is being pulled.
Bob
La Spaziale Dream and Baratza Sette 270W
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chas
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Re: Low Pump Pressure Error

Post by chas »

I believe you are correct. It has only done this to me 2-3 times in 6 months and it always seems to be when I am pulling a shot and drawing hot water at the same time.

I have had all three models of the S1 and I believe this is the only version that has included the ability to detect and flag this condition. Otherwise, all models have worked the same as far as being able to draw hot water while pulling a shot. So I suspect the condition has been there and just been unnoticed in the S1 and the V2.

One thing you definitely don't want to have happen is for the steam boiler element to be out of water and exposed to air for any length of time if it can be avoided. Perhaps it would be better to inhibit the hot water button while the group is active. You still want to be able to steam while you pull a shot and it is always possible that the steam boiler might get a call to refill from drawing off steam but it is much less likely and would definitely be much shorter in duration should it happen at all.

I'll pass this along to CCS with the recommendation. It's hard to tell when/if a change like this might get made. For now at least they might put a note in the manual recommending that you don't use the hot water while pulling a shot.

I know from experience that if the issue was that the 3/8" JG tubing can't supply adequate water volume, the pump would cavitate and make a racket. Since it doesn't do that it probably is just an issue of dividing the flow and therefore the pressure in half by trying to simultaneously supply both boilers.
Chas
LM GS/3 & LaSpaziale Dream v 1.25 (US 120V)
Mazzer Kony E, Customized Rocky
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goodboyr
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Re: Low Pump Pressure Error

Post by goodboyr »

An explanation in the manual is probably fine since it has no discernable effect on shot quality and is not a blocking alarm.

Sent from my SGH-I747M using Tapatalk 4 Beta
Bob
La Spaziale Dream and Baratza Sette 270W
jemery

Re: Low Pump Pressure Error

Post by jemery »

I've seen this too and been wondering about it. I don't have any regulator, but I have noticed it happens most likely when I am pulling a shot and steaming at the same time - which has gotten more common as I have gotten better at timing everything together. Still actually kind of annoying error since it covers the screen with the error and you can no longer see the shot time. I haven;t ever been pulling a shot and hot water at the same time - that seem like it would be unusual scenario. Yeah would be really nice to be able to disable this possibility somehow - even if it just delayed running the steam pump by 30 seconds if the shot pump was running or something like that.
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chas
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Re: Low Pump Pressure Error

Post by chas »

Do you have 1/4" or 3/8" tubing on your water line?
Chas
LM GS/3 & LaSpaziale Dream v 1.25 (US 120V)
Mazzer Kony E, Customized Rocky
Hottop P/B
jemery

Re: Low Pump Pressure Error

Post by jemery »

My tubing is 3/8" white with JG fittings. Mine is a T from my cold water shutoff valve under kitchen sink to a plastic shutoff, then to 10" filter, then to another plastic shutoff, then plastic tubing to the 4' or so braided line to the Dream. One reason the whole line pressure thing doesn't make a lot of sense to me is it doesn't happen if I run water in my sink at the same time as pulling a shot - wouldn;t that be essentially the same as the pump on the steam tank running? I was almost thinking it could be electrical with running the steam pump at the same time. Mine is setup in high power mode on 20A circuit...
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