# Fracino Cherub?



## totallywired (Jun 25, 2011)

Just been offered a second hand Cherub. Had a quick look online at the spec. I see they have a pressure gauge but no temp gauge. Any opinions on the machines? What sort of price would you pay for a second hand one ( ball park )?

Cheers

Dan

P.s would be replacing the trusty old Classic.


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## jimbow (Oct 13, 2011)

I upgraded to a Cherub from a Gaggia Baby Class last year. I am still really impressed with the Cherub and find it is definitely a significant step-up from the classic and there is a noticeable difference in both espresso and milk steaming. The steam power is great and took some getting used to after the Gaggia and the thermosyphonic, E61 style group head delivers amazing thermal stability and consistency to espresso shots. That is not to say it is without issues - the drip tray is ludicrously small and awkward to get in and out of the machine.

The main difference between the two machines is that the Cherub is a heat exchanger design (as found in many commercial machines) compared to the Gaggia single boiler dual use. In practice this means that with the Cherub, one can steam milk and brew coffee at the same time rather than having to activate the steam function and wait for the boiler to reach the new temperature.

The Gaggia boiler is used to heat water to both brewing and steaming temperatures and uses a thermostat on the boiler to control when the heating element on the boiler switches on and off. In comparison, the boiler on the Cherub only heats water for steaming and so uses a pressurestat to control the heating element and maintain a constant steam pressure in the boiler. The higher the setting of the pressurestat, the higher the temperature, and hence higher steam pressure, the boiler will maintain. The pressure gauge on the machine indicates this pressure inside the boiler (usually between 0.8 and 1 bar). Brew water on the Cherub is heated through heat exchange as it passes from the reservoir to the group head inside a copper tube running through the steam boiler. The water inside this copper tube is heated indirectly by the hotter water surrounding it inside the boiler.

I am not sure what a good price for a second hand cherub might be but bear in mind that the price when buying new is relatively low for the specification of machine in the first place. If you shop around you can probably find the Cherub for £650-£700 new.


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## totallywired (Jun 25, 2011)

Thanks Jimbow. Sounds like a great machine. I've done a POV on my classic and this made a huge difference and my only porblem now on the classic is getting consistent temp. Temp consistency on the cherub doesn't sound like a problem. Think this will be my next machine.


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## jimbow (Oct 13, 2011)

Only thing to bear in mind with heat exchangers is that if they are left idle for a while, the brew water sat in the copper tube will become too hot - it will be heated above the ideal 92 degree brewing temp by the hotter water surrounding it inside the steam boiler. Usually, the thermosyphonic group head will compensate for and correct minor temperature variations in the brew water but if the machine has been sat idle then the temperature difference will be too great. To remedy this, before brewing an espresso if sat idle for a period, simply flush a small amount of brew water from the group head to draw fresh, cool water into the heat exchanger circuit.


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## totallywired (Jun 25, 2011)

How long do you have the machine on before pulling a shot 30/40min?


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## jimbow (Oct 13, 2011)

I use a timer plug and set it to come on an hour before I use it. It is usually pretty much up to temperature after 20 minutes but I found that it will benefit from longer if you can. I think it takes a while because of the BIG boiler and the thermosyphon needs time to do its thing.


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## totallywired (Jun 25, 2011)

Nice one. Thanks again for the info.


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## jimbow (Oct 13, 2011)

No problem, here is a thread I started when debating the upgrade with some of my initial experiences:

http://coffeeforums.co.uk/showthread.php?t=4624


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## totallywired (Jun 25, 2011)

Just another quickie. So the hot water outlet, if I wanted to have boiling water for whatever reason could I just turn the machine on and instantly have boiling water or does the machine have to be on for a period of time to heat up? Silly question but would be a good bargaining point when I trying to convince the Mrs I need a new machine.


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## jimbow (Oct 13, 2011)

Not at all - my Mrs is mostly a tea drinker and so that was a track I used too. In the end, she actually liked the look of the machine so much it was not really a problem. In fact, once the machine was in she even asked: "Could we get a better looking grinder?"









Basically the hot water tap is fed from the steam boiler (rather than the heat exchanger/brew water circuit) and uses the steam pressure in the boiler to force the water out the tap. Therefore, the tap can dispense boiling water as soon as the boiler is up to operating temperature/pressure. This takes about 5-10 minutes from switching on.

Having the hot water tap on the steam boiler means that it dispenses water at 100 degrees rather than 92 (brew water temperature). It also enables emptying/flushing the boiler when descaling, etc.

Of course, all the while the machine is on and sitting idle it can dispense boiling water at any time. In the morning, I set mine to come on about an hour before I need it and then switch off just as I am leaving for work. During this time, my wife can dispense boiling water from it at any point (once the boiler is up to temperature of course).


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