How accurate are temperature strips: time lapse video

October 8th, 2015, 11:11 am

I've made a small time lapse video and some photos as reference for temp strip owners. I was surprised how accurate these small strips are.

#2: Post by **Bob_M** » October 8th, 2015, 11:29 am

I have had a similar experience. Using Omega temperature strip and bare wire thermocouple connected to a Fluke 54 II thermometer.

#3: Post by **hipporun** » October 8th, 2015, 11:40 am

Very interesting experiment.

#4: Post by **drgary** » October 8th, 2015, 11:58 am

Another great contribution. I've heard they lose accuracy over time but don't know if that's true. My preference for thermometers is they're more easily seen and tell temperature gradients to the degree.

#5: Post by **homeburrero** » October 9th, 2015, 2:07 pm

Nice work!

I've always thought they were plenty precise once you get familiar with the subtle color transitions. Good to see it carefully studied and documented, thanks! They do have a disadvantage when communicating with others (e.g., "I started my pull when the 80C was going blueish, The 85C was green, and the 90C not yet showing color.")

drgary wrote:I've heard they lose accuracy over time but don't know if that's true.

I've found they get hard to read, just don't show color. Even when new I use a penlight or something to help read them.

#6: Post by **drgary** » October 9th, 2015, 2:14 pm

I'm going to try these on my 1st generation La Pavoni rebuild. Maybe my next mod will be a light like the one I have on my roaster.

Actually I've got a vintage halogen Tensor desk lamp that's just the thing, made at about the same time as my Europiccola.

October 9th, 2015, 3:11 pm

homeburrero wrote:
I've found they get hard to read, just don't show color. Even when new I use a penlight or something to help read them.

They lose color intensity over time. I bought my first one about 2 years ago. I can read it still with the light of my mobile phone but it's a huge difference against a new one of course.

#8: Post by **Paolo** » October 9th, 2015, 3:42 pm

What a great experiment.
I have one of these strips on a few machines. It's one thing to see that the boiler is up to full pressure but another to see when the group has reached operating temperature.

Many thanks, Gabor!

#9: Post by **day** » November 8th, 2015, 11:26 pm

How quickly does the color fade when the temp drops? Gen2 will overheat super fast once bled, so seeing it go up could help approximate for the first shot, but after that...and even after pumping in cool water it will heat up very quickly

November 8th, 2015, 11:44 pm

I found that when I use my cool wet towel at the top and neck of an overheated group, within 30 seconds or so my temp strip (down just above the bell) is indicating a too-cool group temp, which allows me to pump it up a bit to start my shot. That lets me use the same method all the time - always starting my shot after bringing the group up to temp via pumps/flushes.

(I posted about this a while back here: Second pull on La Pavoni Europiccola is too hot - is pressurestat too high? )