While I'm mucking about with the machine I checked the temp of the water- it's coming out about 184F, whereas I think it should be about 204F... Is there a way I can adjust the thermo stat or am I just wrong about the temp?
Jamie

If after a sufficient pre-heat the boiler pressure gauge shows sufficient pressure in the boiler, you're at least generating steam which indicates that the boiler temp is greater than 212F.

More palpably, if you get good steam from the steam wand, flash boiling from the hot water tap, and flash boiling from the group before flushing for at least a few seconds, the boiler water is temped, and everything is jake. If not, not.

Observing those seat of the pants phenomena is more than adequate for determining whether you're system gets hot enough.

You haven't described your methods for taking the water temp, so I am prevented from forming an opinion as to whether or not 184F is accurate. If it is a true representation of the temperature inside the boiler, it's not hot enough for espresso extraction.

BDL

Previous reply is a good one. Beyond that the adjustment would probably be different depending on the age of your machine. Is it a newish one? (You could count the number of buttons on the front to determine it - 5, not counting the on off switch is newer more is older).

Hmm, no, it is about 20 years old I think, '93 and still going strong.
To get the temp I popped my baking thermometer into the shot glass then ran the water through it without the portafilter on. The first time it was in the mid 170s but after that we got to 184, I guess after the glass had warmed up. The thermometer is accurate as I tested it in the kettle and against another one.

Is that after a flush? Water loses a lot of heat dropping through the air and the cup will suck a lot of heat out. Thermometers are also very slow to respond and not that accurate. You really need a thermocouple to get an accurate reading. You can also stick the thermometer thought the bottom side of a Styrofoam cup and run your water into it. The Styrofoam will lose less heat than an espresso cup. How long has the machine heated? The 60's series machines really need an hour to heat properly.

Right.

The temperature of the water in the cup is going to be cooler than the brew water as it enters the pf from the group -- for several reasons.

Another curiosity is that only some DB machines deliver water at a constant temperature throughout the duration of a pull. With most machines and all other types, the temperature begins to fall at some point during the pull, then continues to fall throughout. Some machines won't give a constant rate of decrease and/or begin the pull with a brief temp rise, giving a characteristic temperature "hump" which greatly influences shot quality.

La Marzocco and La Cimbali are two brands of machines known for their happy humping. On the other hand, machines with thermosyphonic groups tend to produce flatter temp curves. Your T1 is a thermosyphonic, but I can't remember offhand what it's temp curve looks like. Maybe an owner can jump in.

If you want to get close to the actual temperature of the brew water -- at any time during the pull -- you're going to need a thermometer mounted in the group or the pf. Someone rents (or used to rent) 58mm pfs equipped with an electronic thermocouple (aka Scace 1) and a meter to read it for around $50/week.

For awhile before PID machines equipped with digital displays became commonplace, and before the taste limits of coffee brewed with a very flat temp profile were known, accurate thermometric information was something of the dernier cri among serious home baristas, and a way which allowed them to recognize one another before moving on to the secret handshake.

But once everyone and his aunt could tell temp to the nearest degree F, it became apparent that the information didn't flatten the learning curve required to brew a decent shot by very much. If you were going to pull a crap shot without an accurate temperature display, odds were you'd pull the same crap shot with it.

My own feeling is that when it comes to an HX, accurate thermometric data for group water temp is more about curiosity than utility. If:

• (1) You know whether or not the machine can produced water too hot to brew (manifested by flash boiling);
  (2) You are able to use the machine to flush the water to Goldilocks' "just right" temps using seat of the pants measurements like listening for the end of the flash boil, and counting elapsed time of the flush afterwards -- "one cappuccino, two cappuccino;" and
  (3) The machine can then hold the appropriate temperature range throughout the pull (don't dilly-dally), then for practical purposes,
  (4) You're good to go.

Nothing wrong with satisfying curiosity though.

BDL

The 60 series produces a relatively flat temp profile. They are best used with a flush and go, no rebound time is needed. The temps stay within a half degree through a shot with an inclining profile. After 30 seconds the temps start to raise quickly but that is the side effect of a big boiler/heater and heat exchanger. Plus side, you can pull shots as fast as you can work the machine without giving the machine any recovery time between shots. For a 'real' temperature profile you need a Scace device but the thermocouple in a Styrofoam cup will get you a reasonable brew temp guess.

The depth of knowledge on this board always astounds me.
Thanks folks, I'll sot down and try to figure out next steps.
Jamie