La Marzocco GS/3 - fried logic board? - Page 4

Need help with equipment usage or want to share your latest discovery?
kzdad
Supporter ♡
Posts: 23
Joined: 14 years ago

#31: Post by kzdad »

Glad you were able to salvage your board. I am one of the three people who have reported a similar issue (mine was one of the fire sale machines). After fitting the new vacuum breaker assembly and replacing the steam boiler gaskets, I've had no further issues. I don't have my machine plumbed in so when I see the water tank seemingly starting to drain on its own, I know the vacuum breaker is in need of a good cleaning, about every six months.

I agree 100% with a previous comment about the need to keep the machine well maintained.

Billc
Posts: 304
Joined: 15 years ago

#32: Post by Billc »

Most of the issues are caused from water under the board (between the box and the board). The issue is usually the low voltage components being shorted. Typically this does not permanently damage the board (unless you hear a loud POP). Most can be revived by drying out before turning on again.

Just FYI. Sorry for the poor design.

BillC

User avatar
AssafL
Posts: 2588
Joined: 14 years ago

#33: Post by AssafL replying to Billc »

Bill - Is there a reason LM doesn't use a conformal coating on the board? Shouldn't that prevent most fried boards from water shorting?
BTW - The last board didn't die with a pop. The coffee boiler output stopped working altogether after water leaked into the plastic box. Possibly a bad transistor.
Scraping away (slowly) at the tyranny of biases and dogma.

User avatar
Peppersass
Posts: 3690
Joined: 15 years ago

#34: Post by Peppersass »

Billc wrote:Most of the issues are caused from water under the board (between the box and the board). The issue is usually the low voltage components being shorted. Typically this does not permanently damage the board (unless you hear a loud POP). Most can be revived by drying out before turning on again.

Just FYI. Sorry for the poor design.

BillC
In my case, the board survived several episodes of water leaking into the brain box. Then one time it didn't. No amount of drying would revive it. I didn't hear a loud pop, but I may not have been in the room if and when it happened.

In fact, I'm pretty sure my board had water on it the first time I fired up the machine back in October of 2009. The machine would spontaneously reboot every now and then. Pretty harmless, though it could throw off the shot timer if it happened during a pull. After some correspondence with Bill, I pulled the board. Didn't see any water, but I dried it gently with a hair dryer set on low, plugged it back in and never had the problem again. Could have been a loose connection, but I think it's more likely the defective steam boiler seals had leaked during transport (they only leaked when cold.) That problem recurred on and off for several years with the logic board showing different symptoms -- usually steam boiler overfill. Then the board finally fried. That's when I noticed tiny drops of water leaking from the steam boiler seals.

As I've said several times, leaky steam boiler seals was a rare problem that seemed to have occurred in only a handful of the infamous fire-sale machines. FWIW, I still have the machine and would not part with it (especially since I tricked it out for pressure profiling with a gear pump!)

And Bill, aside from the location of the brain box, I think most would agree that the GS/3 design is downright brilliant.

Billc
Posts: 304
Joined: 15 years ago

#35: Post by Billc »

Dick,
Thanks for the kind words. I like the location of the brain just don't like the way it turned out. I should have made more of an effort to make the box more water resistant.


Comformal coating would work OK as long as it is not too thick. This is actually a very expensive (relative) process in low quantity. The reason is that it is done by hand with a small paint brush.

If any of you saved the old boards I would love to have a look at them. I may even be able to fix them.


BillC

User avatar
AssafL
Posts: 2588
Joined: 14 years ago

#36: Post by AssafL »

I agree that it is an awesome machine. Love it, and intend to keep it alive for many many more years. BTW - replacing the steam boiler gasket - got a glimpse inside the boiler. After 4.5 years - still looks brand new. Spotless.

A serious issue with these machines is that like commercial machines, they must be serviced every few years. Mine has been in continuous operation for over 4 years. I think it is time for full service.
1. Gaskets are nearing end of life. for example, the HX gasket (VITON) I replaced got baked in a triangular cross section and lost any trace of flexibility.
2. Check valves nead cleaning and sometimes replacing (I assume the VITON gaskets in those also bake - especially in the boiling water lines).
3. Everything needs inspection and a through cleaning.
Us home users do not have service contracts and don't know what and when we should service to prevent aging seals and baked silicon grease from turining into an expensive catastrophe. I wonder if La Marzocco can share their recommended service plans for Lineas or Strada so we could prep for service?

Regarding the GICAR logic board: I think the logic board gets water by capillary from the cables. Water creeps along the cables. That is also the reason it is impossible to seal the plastic box.

Flipping the board and power switch would solve the problem (as the board would be affixed to the top of the plastic case and water would be unable to creep up the cables).

Bill - I use aerosol conformal coating and did about 2-3 layers. Simple and cheap.
I also have the original board. It had two issues - Battery wouldn't keep time and brew boiler SSR drive faulty. Let me know if you want it.
Scraping away (slowly) at the tyranny of biases and dogma.

User avatar
Peppersass
Posts: 3690
Joined: 15 years ago

#37: Post by Peppersass »

AssafL wrote:Regarding the GICAR logic board: I think the logic board gets water by capillary from the cables. Water creeps along the cables. That is also the reason it is impossible to seal the plastic box.
Yes, I agree.

User avatar
FotonDrv
Supporter ♡
Posts: 3748
Joined: 11 years ago

#38: Post by FotonDrv »

Billc wrote:Dick,
Thanks for the kind words. I like the location of the brain just don't like the way it turned out. I should have made more of an effort to make the box more water resistant.


Comformal coating would work OK as long as it is not too thick. This is actually a very expensive (relative) process in low quantity. The reason is that it is done by hand with a small paint brush.

If any of you saved the old boards I would love to have a look at them. I may even be able to fix them.


BillC
Bill: I understand that putting the electronics under the machine since it is the coolest place inside the case. Did you consider making the machine a bit wider or deeper and putting the electronics in a separate, insulated and vented, box and then enclose for appearances??

Stephen
That Light at the End of the Tunnel is actually a train

Post Reply