to recap: the expobar office control -- aka carlos -- born in valencia, spain on april 2003, has a pressurestat in the front right of the case, 1/3 of the way up off the floor.
it is shaped like a squat cylinder, or as i said before for a skirt-friendly analogy, like a pot of lip balm (kiehls, carmex, you get the idea.) the p-stat has a yellow face with a red cap.
in some models, this face smiles forward to the front of the case, in others upwards to the top of the machine. mine faces upwards.
other expobar models or those built at different times have different shaped and sized p-stats that are located elsewhere and that are adjusted differently. you must know your model and your birthdate. . .
my carlos was clearly too hot. the coffee tasted bitter and burnt; the milk scalded and evaporated before it foamed; all this even after running 4-6 oz. water outta the group.
so to adjust carlos' p-stat to lower his temperature: start with a cold, unplugged machine. tools required: phillips head screwdriver, needlenose pliers, 3.5mm computer screwdriver, a small flashlight.
a third hand helps to hold the p-stat so it doesn't twist during adjustment; it's on a flexible pipe. remove the 4 screws in the lid. remove the drip tray. remove the 2 screws of the faceplate.
on mine, i had to recruit husband, mr. right, because the red cap is on tight and is a little slippery. he had to slide the needlenose pliers in from the left to avoid the wire bundle that hangs in front of the p-stat.
i held the p-stat in place from below. he tugged gently, gently, gently. did i say gently? the cap comes off.
the cap conceals a little "well." the lip of the well has notches around it, and on the face of the p-stat, covered by the cap, are the curved adjustment scale arrows with a plus and minus at each end.
they are hard to see. use your flashlight.
the tiny adjustment screw is sunk into the well. to lower pressurestat, turn clockwise with computer screwdriver. the p-stat in its housing may sink a tad when you press on it, gently, gently.
mr. right adjusted the screw about 1-1/2 notches clockwise. i put the faceplate on and heated up the machine. 10 mins. later i ran my 6 oz. water, then measured the temp of the group water with the instant-read-stick-thermometer-stuck-in-the-base-of-a-foam-cup method.
resulting water temp: about 185 degrees. too low, i thought. since before adjustment i had water readings of 202, it was a big change. i was aiming for about 194-195 in the cup.
so i tried steaming. ah-a! i actually got some foam before the milk scalded! improvement! tried making some espresso, both batdorf's dancing goat and gillies deluxe dark 2.
i was sure it was going to be sour. actually, the batdorf was pretty good -- it's a darker roast than the gillies. it was drinkable without sugar. i didn't find it sour, and while the crema was more toasted-almond-brown than deep hazelnut skin/pompeii red, it seemed fine.
the gillies is a lighter roast coffee and it did suffer in the crema more. but again, it didn't need sugar and didn't seem sour. this puzzles me. 185 is waaay cold, right?
my silvia is the old 110 degree thermostat model. if i heat silvia for 20 mins., draw off 2oz. water, then surf by waiting 20 seconds, i get 192-194 on the water test. if i heat carlos for 10 mins., draw off 2oz. water, wait for 10 seconds, then test, i also get 192-194 degree water.
running off 4-6oz. of that volvic (and here) for every shot on carlos is expensive. . . so, i'm tempted to try leaving carlos where he is for a week or 2.
also, i have to publicly thank todd of wholelattelove, who was nice enough to talk to me this morning on his weekend. what a sweetie!