HB wrote:I noted that Junior was among the slower machines to warm up and recommended at least 90 minutes in the review. You have been posting a lot of temperature plots lately, why not test your assertion? A plot of the first few pulls with the thermofilter for your espresso machine being on for two hours and another series after idling a half day should settle the question (at least for Junior).

Hi Dan,

I'm on a temperature plotting hiatus. For one thing, I'm sick of doing it, and for another there hasn't been much of a response to what has been a huge "time sink," so I'm not highly motivated to bother. My experience with seals and gaskets is that if anything they last longer when the machine is on 24/7 then when there are repeated cycles of heating up and cooling back down. I've had problems with vacuum breakers when the machines were run on a timer and almost never (or at least it took 3 years) when run continuously. I am unconvinced that the savings in my electric bill would exceed a couple of bucks a month running the thing on a timer.

The safety argument is similarly uncompelling. If the machine is well taken care of I think leaving it on is as safe as leaving your water heater turned on, or the furnace, for that matter. Why the emphasis on potential danger from an espresso machine? Are they so much more "dangerous" to have around that they need special precautions? Why on earth don't the insurance companies have an exclusion in their policies for damage done by espresso machines? Boggles the mind!

So, I'm not motivated to test this at the moment.

ken

Ken Fox wrote:I am unconvinced that the savings in my electric bill would exceed a couple of bucks a month running the thing on a timer.

Last time I calculated the cost, it came to a few dollars per month not including the added burden on the A/C during the summer.

Why the emphasis on potential danger from an espresso machine?

I don't think they are dangerous, but I irrationally worry about anything that is continuously hot. Sleeping with the oven on would make me equally nervous, or leaving on vacation without cutting off the water service (the plumbing of three houses on our street have failed, fortunately while the owners were home so the damage was minimal).

By the way, don't take my lack of response to your prior threads on temperature stability of a PID'd HX espresso machine as disinterest - it's a lot of information to absorb! My first thought was "why not PID the steam boiler and automate the cooling flush with a second thermocouple at the brewhead thereby delivering on the fly temperature selection and fantastic temperature stability?" My hope is that the Monster Bric project that Chris and TerryZ keep mumbling about will do just that.

HB wrote:Reminds me of an old joke: A service technician, hardware engineer, and programmer are driving down the highway and get a flat. The engineer says they should diagnose the failure by downloading data from the car's onboard computer. The tech advises simply replacing all four tires. The programmer suggests they keep driving and hope the problem goes away.

A call to tech support resulted in the following advice: "Hit the 'start button' to turn it off, roll down the windows and get out. Turn it on again, roll up the windows, and re-install the driver."
So, even if I am a 'Home Barista', I'm currently wielding a pro two-group machine, an Astoria Argenta (the big gulp version). The recommendation I got from the local espresso machine repair gunslingers was to keep the thing on constantly. The did say that I'd have to replace the PF gaskets two or three times a year, but twenty-five (at the most) bucks it'd take to do that was well worth it. Anything else that went due to heat cycling would cost at least that much.

To my mind you can separate the arguments, for example:

- Commercial v Home: I'm assuming we're all talking about the latter

- Energy conscience: Many forums of various pastimes are touching on this, it's in the psyche of all us somewhere with doing our bit for the planet. Despite all the arguments about the white good, automotive, flat-tv markets etc. etc. etc. which spin product cycles out with alarming frequency and the energy, pollution, water wastage issues of it all everyone seems to feel they should still try and do their little bit. We all wrestle with leaving our coffee machines, audio etc. on

- quality of shots: Life tends to be too fast to worry too much for someone like me.

- routine & convenience: I'm happy with the timer half an hour before I wake, a luxury compared with previous manual Pavoni. By the time I get to make a Capp in the morning my Brewtus II has warmed up for an hour. It then powers down around the time I leave for work and I have it set to come on at 7pm and go off at 11pm (different times at weekends). I see no point it being on when I'm out all day

- safety: I also struggle with the idea of something being on 24x7 when I'm out for large spells of it if something did go wrong. I leave things on at the weekend generally but turn off at night. Somehow I prefer a routine which makes me think about it coming on and off, checking water (not plumbed in until I move), backflushing, scheduling a descale etc.

- technical knowledge: bottom line is that some folk such as myself simply don't have a lot of it and therefore go by instinct. Often wrong of course otherwise we wouldn't learn a lot through the years!

I have had my Gaggia Carezza for 6 months now and have been leaving it on 24/7 only in the past 3 months or so, mainly out of laziness. We pull at least 6-8 shots per day, every day, and today the gasket died. I can only assume it is secondary to leaving the machine on, drying the gasket out. One of the two clear silicone tubes that draw water from the reservoir is also becoming quite deformed, expanding and turning white, splitting at the end, and it must be because that water, just by being next to the machine, stays pretty hot.

I think 6 months is pretty early to be changing the gasket but you can bet I'll put a timer on the machine and use that from now on. The stress of being without espresso for the several days it will take to get the new gasket is not worth it, lol.

Psyd wrote:The recommendation I got from the local espresso machine repair gunslingers was to keep the thing on constantly. The did say that I'd have to replace the PF gaskets two or three times a year, but twenty-five (at the most) bucks it'd take to do that was well worth it. Anything else that went due to heat cycling would cost at least that much.

I can appreciate the convenience of always-on espresso machines, especially for commercial units that demand hours to stabilize. But I've still not heard any compelling evidence tying premature component failures to on/off cycling. Simply put: What components are more likely to fail if a machine is run four hours a day versus 24/7?

In past discussions, I've read the following disadvantages of on/off cycling:

• Inconvenient if one must wait, or added expense if one buys a timer; risk that machines without auto-refill with be turned on without water and burn out the heating element; risk that brew switch will be inadvertently be left in on position and burn out pump when timer starts it
• Increases scale build-up at the boiler's waterline
• "Stresses" connections of dissimilar metals (How does this manifest itself as a failure - boiler leaks? If so, from where?)
• Electronic components are subjected to changing temperatures, which increases the likelihood of them failing. The argument that failures are more common with frequently cycled computers is often cited in the same context
• Sensitive electronic components are subjected to electrical spikes when machine is turned on/off

I've read the following advantages of on/off cycling:

• Saves energy
• Increases the lifespan of gaskets
• Reduced usage decreases pressurestat's carbon buildup, which is the leading cause of failure
• Some "weaker" connections are made of nylon or plastic (tees, insulators). Exposure to less heat reduces their failure rates
• Reduced exposure to high temperatures increases the lifespan of sensitive electronic components like controllers (note: applies mostly to prosumer / semi-commercial machines; they are located outside of the case of most commercial units)

Looking at the list above, the one that sticks out for me is the pressurestat. They cost around $40-$60. If I remember correctly, that roughly equates to the added energy cost of approximately two years' 24/7 operation. It wouldn't surprise me if 24/7 operation would decrease some pressurestat's lifespan by that much (e.g., CEME, MATER).

The calculations for a cafe are a lot easier. If the cafe closes at 10pm and reopens around 6am, realistically they have little choice but to run 24/7. For those with machines that warm up in 30-60 minutes, it's an option. Is on/off cycling a more economical option? I don't know for certain, but my guess is yes, it is for most prosumer / semi-commercial units.

I took the easy way out- When I purchased my A3 6 or 7 months ago now (wow, has it really been that long!?!) I asked Chris himself at Chris Coffee for his recommendations in this regard. The answer was: leave it on 24/7. That was good enough for me... The big Elektra is going strong with one great effortless shot after another!

HB wrote:They are equally likely to fail to reboot because of software errors, missing scripts, passwords not entered, dependent server not finished rebooting, etc. You could argue that the auto-fill controller board is like a computer, but beyond that the comparison of espresso machines and servers is a real stretch.

Even more fun, >RM the kernel on a UNIX box after boot. It pushes it into RAM and never looks at it again, unless you reboot, then you have no OS.

But as to the on or off question, for me it varies. When I had my Isomac at home, I had a timer on it. It came on at 6am so it was hot and ready when I came downstairs, then turned off as I walked out the door. Then back on again at 4pm so it was ready when I got home and off again at 7pm. Ran that way for almost a year, no problems. Now I have it in my office. I turn it on when I get to work and turn it off as I shut down my computer.

My 2 group Faema is a bit different. Instead of a half hour heat up, it is at least an hour and a half, two hours is best. During the winter I let it run 24/7 but now that summer is here, I don't want it pumping heat into the house all day. So when the dog gets up at 4am to be let out, the wife or I turn it on. Then off when I leave for work, then on again around 4pm and off around 7pm. No timer on this guy, 220v. Then there are those mornings that it gets missed, so I power up the lever machine.

cannonfodder wrote: So when the dog gets up at 4am to be let out,

Obviously, you need a new dog!

cannonfodder wrote:No timer on this guy, 220v. Then there are those mornings that it gets missed, so I power up the lever machine.

Really, I just open a window right next to my two-group and the heat tends to go out the window. Incoming air from the cooler is from the opposite side of the room, so I get a flow. The dog door works on the exact same pressurize-the-room theory... ; >

Dogshot wrote:I have a dual boiler machine (BII), with both boilers insulated. I currently have the machine on a timer to turn on at 6:00am and off at 8:30pm.

I use the machine throughout the day, 7 days a week. Electricity consumption aside, what is better for the machine - to just leave it on 24/7 or turn it off over night? If it has different effects on different parts, which is better from an expensive or difficult servicing issue? For example, does leaving it on 24/7 age the electronics faster? Is it good or bad to 'exercise' the vacuum breaker by turning off regularly? etc.

Thanks, Mark.

I left my BII on for long periods at a time and noticed the water in the reservoir was warm and the reservoir tubes became slimy like a neglected fish tank.

Doug
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