Unstable E-61 group temperature reading.
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F1
- Posts: 699
- Joined: 13 years ago
Not the first time I have had a temperature problem with my Giotto PP V2. At least this time the espresso shot's flavor seems unaffected. This is actually the third temperature issue with this machine in over two years. For the first two issues the solution was something different. The first two issues were thermosyphone stalls caused by the OPV gasket first and second by the brew valve gasket. I also had an issue with flavor that lasted several months and it went away once I changed the second OPV ball-valve that some Rocket machines use.
Symptoms:
I have an Eric's thermometer in the group. I have had it for years. At a Pstat setting of 1.0min-1.2max the group reads 207F after 1hr idle. It would deviate by no more than +/-.5F if left idle for hours/days. As of two weeks ago I saw the temperature at 204.5F after 1hr idle. Two hours later it was 205.5F and for the whole day it never went above this. I pulled several shots during the day and the temperature after 1hr would sometimes be 205F, 206F, 203.5F. So for the next couple of days I decided to leave the machine idle for hours and check what the reading was at different times of the day. Again, the temperature would deviate from as low as 203.5F up to 207.5F.
What I did:
The first thing that came to mind was thermosyphon stall, but since the temperature doesn't keep heading down non-stop I ruled that out.
- Changed the thermometer's battery.
- Checked the mushroom for scale, but it was clean.
- Removed the Anti-vacuum valve to take a peek inside the boiler with a flashlight. Not a trace of scale buildup.
- Removed the water line that feeds the OPV to see if there was a small leak from the OPV. Nothing.
- Looked and listened for leaks with the case open even though a leak would cause the temperature to keep going down non-stop. No leaks.
- I got a spare PSTAT, but since the old one(6 months old) is cycling as normal I decided not to try the new one.
- And, NO the machine is not close to a window where some cool breeze could be lowering the group temperature. The Air temperature inside of my house changes during the day +/-10 degrees, but in the past this has not had any effect on the group temperature.
Any ideas?
Symptoms:
I have an Eric's thermometer in the group. I have had it for years. At a Pstat setting of 1.0min-1.2max the group reads 207F after 1hr idle. It would deviate by no more than +/-.5F if left idle for hours/days. As of two weeks ago I saw the temperature at 204.5F after 1hr idle. Two hours later it was 205.5F and for the whole day it never went above this. I pulled several shots during the day and the temperature after 1hr would sometimes be 205F, 206F, 203.5F. So for the next couple of days I decided to leave the machine idle for hours and check what the reading was at different times of the day. Again, the temperature would deviate from as low as 203.5F up to 207.5F.
What I did:
The first thing that came to mind was thermosyphon stall, but since the temperature doesn't keep heading down non-stop I ruled that out.
- Changed the thermometer's battery.
- Checked the mushroom for scale, but it was clean.
- Removed the Anti-vacuum valve to take a peek inside the boiler with a flashlight. Not a trace of scale buildup.
- Removed the water line that feeds the OPV to see if there was a small leak from the OPV. Nothing.
- Looked and listened for leaks with the case open even though a leak would cause the temperature to keep going down non-stop. No leaks.
- I got a spare PSTAT, but since the old one(6 months old) is cycling as normal I decided not to try the new one.
- And, NO the machine is not close to a window where some cool breeze could be lowering the group temperature. The Air temperature inside of my house changes during the day +/-10 degrees, but in the past this has not had any effect on the group temperature.
Any ideas?
