Gaggia Classic - won't stop heating
Not sure what I have done wrong. I installed a C100 PIDand thought I followed all instructions but heating continued past the alarms.
I then took the PID out and the problemremains.
Checking the wiring it seems fine (compared to photos onhere) but obviously isn't. I left the PID powered and have kept the temp probeagainst the boiler.
I have both the original thermostats wired. The machineis a really old one – about 17 years but had a break for 6 years when I had asuper automatic.
When I power on the brew light comes on at about 80 degreesbut heating stays on till I turn the machine off (about 160 degrees).
Any advice on what it could be would be welcomed. I guesssomething really simple.
Not a simple diagnostic, as you have so many new things to potentially install incorrectly! PID, wiring, SSR’s (assuming steam and brew?).
If the issue still remains after the PID is removed, and you are certain you have the stock wiring correct, then it sounds most likely like a thermostat issue. The brew thermostat is on the left side of the boiler when looking from the front.
Does the steam setting work correctly? This should be a seperate circuit and not be affected by the brew temperature overshoot issue. If both circuits are affected, then your stock wiring is likely incorrect and may also explain why the PID is also having issues. Double check your wiring.
How did you keep the PID temperature probe attached when testing with the stock thermostats?
What temperature sensor are you using for the PID? Did you change the probe setting so it reads the signal correctly?
The Gaggia Classic with PID is not a very common topic here. You can try the UK coffee forum with a dedicated section for Gaggia machines. I use a Gaggia Classic with an Auber PID kit installed. I am not famliar with the C100 but if you provide pictures and diagrams on how you wired it, I might be able to help.