Regarding the thread about backflushing. It sounds like a great idea, and you all say it is and I surely believe you, but why wouldn't it be recommended by the company? I just finished re-reading the section on taking care of my Baby Class, and it's not mentioned in the owners manual.

For some reason, I seem to think that I came across this question once before...but I don't remember who to give credit to for the information....

I seem to remember reading something that said that the very hot water that comes rushing out of the 3-way valve when you're done backflushing can supposedly splash up out of the drip tray, and Gaggia doesn't want to be responsible for burns, so they don't recommend it. Again, I don't remember where I read that, or who wrote it. There's a very good chance that it was just someone's speculation on the very question you're asking.

The things companies do to avoid being sued...

Ah well then, that would make some sense. And given the huge anti-company contingent in this country, who could really blame them?

The "splashing water" concern sounds like corporate double-speak. We are talking about a machine that is created to dispense VERY hot water with many hot metal parts exposed. Is there a safety interlock that keeps the machine from spewing hot water out of the brewhead if the portafilter is not in place? And Gaggia also makes machines NOT equipped with a 3-way that spits out hot water and coffee particles all over if care is not taken. Do those include a warning not to use coffee or water in them? If water splashes when backflushing it is a design flaw of the 3-way outlet or the drip tray. Why, then, include a part whose function causes coffee oils and particles to be deposited into the machine in areas that cannot be reached and then tell consumers that they shouldn't take steps to clean these areas?

I'm a Silvia and Alexia owner. I backflush and think it's both safe and necessary.

But...

Backflushing might be risky on a machine with a non-functioning OPV. With a blind filter and an inoperative OPV, the pressure could max out the pump (presumably 15 bar / 200 psi or thereabouts). Perhaps the Gaggia folks are concerned about failure of boiler seals, tubing and connections, etc. that may not have been designed to max out the pump?

The theory could be that even a too-finely ground coffee puck will allow pressure relief before reaching 15 bar, while a blind filter allows none. Or that the consumer would notice "something wrong" (like no coffee coming out) before the pump had ramped all the way up with a "choked shot."

If I'm a product safety engineer, and I think that OPV's are unreliable in this context, then I probably err on the side of safety and recommend against backflushing. A consumer could use their machine for years without knowing the OPV was jammed shut, so it may not be completely unreasonable (and perhaps even responsible) for a manufacturer to take a "no-backflush" position.

Probably a more reasonable approach would be to suggest that you confirm proper operation of your OPV, and then backflush.

Just food for thought, and a hypothetical answer to the OP's question.

Jim

Well, looking more at the manuals, comparing the Carezza manual and the Baby Class manual, I'm surprised at how similar the two are. I didn't compare word-for-word, but most of the manuals look/read exactly the same. For example, the pages even line up. I.E. page 15 of the Baby Class manual looks exactly the same as page 15 of the Carezza manual. I guess what I'm saying is that I suspect that Gaggia tried to re-use the text of one manual as much as they could.
One note: the Baby Class manual doesn't even mention anything about a 3-way valve. At least I couldn't find anything using the search function of my PDF reader. I tried searching quite a few things, like three-way, 3-way, 3, 3 way, valve, solenoid, etc..., and nothing showed up.
Also, about the "PF sneeze," both manuals say:

Gaggia manual, p. 15 wrote:To make more espresso, carefully and slowly remove the filter holder by moving handle to the left. Be careful as hot water will be on top of the coffee grinds in the holder. Some water will continue to drip from brewing head as filter holder is removed. That is normal and due to the pump pressure in the system.

Here's links, if anyone else wants to compare the manuals.
Carezza manual
Baby Class manual

Most Gaggias do not have a 3 way valve which is required to back flush. I have a Carezza which does not have and the Baby Class which does.

Whole Latte Loves site has a compare sheet that will let you look at all the Gaggia models specs in case you are interested.

Silvias manual also recommends not back flushing but I think most people do so anyway. They just don't do it for too long at one time.

Dan

FC+ wrote:Regarding the thread about backflushing. It sounds like a great idea, and you all say it is and I surely believe you, but why wouldn't it be recommended by the company? I just finished re-reading the section on taking care of my Baby Class, and it's not mentioned in the owners manual.

I've been reading a bunch of interesting info here about backflushing and I am about to do the same to mine (have used it now for 4-5 months without a single backflush...however, I have descaled). I have a Pro Line and I'm sure that I read somewhere that these have a 3-way value which will allow safe backflushing. Can anyone confirm that?

PaulM wrote:I have a Pro Line and I'm sure that I read somewhere that these have a 3-way value which will allow safe backflushing. Can anyone confirm that?

Yes, through the power of a website called "Google." You really should try it:
"kitchenaid pro line espresso machine 3-way valve"

Well, the blind is ordered. Old dog, new tricks, this ought to be interesting.