Scace Temperature Reading on Londinium 1-P

#1: Post by **FotonDrv** » September 15th, 2016, 12:06 am

This is what I found when I finally got around to testing the temperatures on my L1-P.

There was a previous Thread on this topic but the Levers they tested apparently were Groups bolted to the boilers and nobody had tried the Londinium machines. I know the L-1 has a different boiler configuration and this L1-P so I would suspect different readings if someone has taken the time to check them.

I tried lowering the boiler pressure down so it reached a maximum of 1bar when the Pstat cut off the boiler power and fell to about .75bar at idle.

I have since returned the pressure to 1.2bar at idle and the temps went back up again.

#2: Post by **aecletec** » September 15th, 2016, 3:06 am

Would I be wrong in thinking those are some consistently high temperatures?
An argument I recall is that levers allow hotter water to cool after hitting the lower temp group and gradually decline thereafter but that didn't seem to happen to a point where I'd be comfortable brewing at in this case?

#3: Post by **CoffeeBar** » September 15th, 2016, 3:22 am

first time saw Scace in action in lever machine, nice video

#4: Post by **Bak Ta Lo** » September 15th, 2016, 3:36 am

FotonDrv wrote:This is what I found when I finally got around to testing the temperatures on my L1-P.

Hi Stephen, thanks for the test and vids.

I am not clear what is happening in that first video, it seems as if a L1-P sitting at idle with no flush is pulling a 218 degree shot. Is that right? It is really hot isn't it?

The second video with a flush pulls the shot at an excellent temperature.

It seems the temps are more related to flushing than the p-stat setting. Maybe I am misunderstanding the test or video?

September 15th, 2016, 4:00 am

The related topic:

Apparent Overheating of Lever Espresso Machines Measured with Scace Thermofilter

I am quite baffled actually. There were some Scace pulls that did not show overheating but some did. I am pretty sure those that show overheat tastes fine - it's quite obvious when it's burned to not notice. It must have been down to the the measuring technique/process.

At idle, hx water temp(L1-P) = boiler water temp (L1). I am not expecting that much difference in temp reading.

Someone mentioned in the past(think it was JohnB) that you could block the inlet to simulate the lever preinfusion (with a oven mitten or glove). Maybe that will give a more 'appropriate' reading in relation to pump? Stephen, could you try that?

#6: Post by **Bak Ta Lo** » September 15th, 2016, 4:19 am

samuellaw178 wrote:A related topic:

Apparent Overheating of Lever Espresso Machines Measured with Scace Thermofilter

I am quite baffled actually. There were some Scace pulls that did not show overheating but some did. I am pretty sure those that show overheat tastes fine - it's quite obvious when it's burned to not notice. It must have been down to the the measuring technique/process.

At idle, hx water temp(L1-P) = boiler water temp (L1). I am not expecting that much difference in temp reading.

Someone mentioned in the past(think it was JohnB) that you could block the inlet to simulate the lever preinfusion (with a oven mitten or glove). Maybe that will give a more 'appropriate' reading in relation to pump? Stephen, could you try that?

Aha, thanks Sam, that thread covers all of this exactly, I had missed that one. So the take-a-way on this is to never test and assume you are looking at the actual brew temp in that style of flowing Scace device, it is OK to use it to test consistency in temps, but it is not showing actual brew temp, due to all the reasons explained in the a linked thread. As the L1-P is a cold fed Thermosyphon flushing it to get the right temp on the Scace would result possibly in a too low of a temp when using a proper basket of coffee with the same flush. It seems that L1-P at idle showing 218 degree shots with the Scace is probably the correct temp to allow for heat sink effect from when there is a coffee puck in place. Same as the videos in the other thread with the Prestina.

#7: Post by **aecletec** » September 15th, 2016, 6:10 am

It was good to re-read that, I had forgotten the conclusions!

September 15th, 2016, 6:32 am

Bak Ta Lo wrote: As the L1-P is a cold fed Thermosyphon flushing it to get the right temp on the Scace would result possibly in a too low of a temp when using a proper basket of coffee with the same flush. It seems that L1-P at idle showing 218 degree shots with the Scace is probably the correct temp to allow for heat sink effect from when there is a coffee puck in place. Same as the videos in the other thread with the Prestina.

No worries Jeremy! Your interpretation is similar to mine and my experience. That much flush on my Brugnetti Aurora (a HX lever as well) definitely results in too cool a shot. I've rigged up a thermofilter for measuring temp (it doesn't show superheated temp though), but tasting remains the most accurate method to dial in the temperature.

The only thing that doesn't add up is, there're a few videos that show ok temp with Scace.

Here's AndyS's L1

-removed reference to Rick's video as he's using his own thermofilter which may have a different spec and not the official Scace-

#9: Post by **Bak Ta Lo** » September 15th, 2016, 7:05 am

Sam, ok I get your point now. The videos between the different thermosyphon (just use TS to save typing) levers are showing totally different results from a no flush shot, on the Scace.

The L1 Andy shows is a boiler fed TS (from what I understand, that may be the wrong name for that kind of setup), and the L1-P is a line fed TS. This actually confuses me more, why is the L1-P's line fed TS pulling shots at near boiling water temps? Andy's L-1 is pulling low 200's as well as Rick's, not sure what machine Rick is using there. Also, hard to see what the pressure is set to in those videos. If they are running the brew boiler at .7 or .8 it could be cooler boiler water than Stephen's set at 1 or 1.2, correct?

My guess is this would only happen after a long idle where the water in the TS has had time to reach boiler temp. On my Strega I always flush the flash boil water just as I remove the basket to prepare a shot, if it has been idle for more than a few minutes. This is very short 30ml flush. Then I take thirty seconds to a minute to prepare the next shot. This seems to give me a consistent good shot (of course the Strega's electrically heated group makes the comaparison not really apples to apples).

Sorry to those who have suffered this topic countless times, I'm slow to fully get these thermodynamics clear in my brain. But, I'm always intrigued by all the mechanical solutions that have been designed to allow the levers to brew at the correct temp when drawing from a boiler full of pressurized hot water. It's fascinating to me.

Hope Stephen can do the test as John B suggests with the towel on the Scace. Or, taste test the shots for us between the flushed and unflushed group.

September 15th, 2016, 8:51 am

Bak Ta Lo wrote: Hope Stephen can do the test as John B suggests with the towel on the Scace. Or, taste test the shots for us between the flushed and unflushed group.

Yeah, this would be a great follow-up. Give us the numbers, and then tell us what they mean!