Thank you for all the guidance and assistance! I reviewed my photos and I believe the heat source can most likely be attributed to a water leak originating from the component indicated by the green arrow. I'm unsure of the name of that part.





As for the 160˚Quick Mill Safety limit thermostat, the metal was noticeably corroded. I've managed to remove the rust using a metal file. Do you think that's adequate, or should I consider replacing it? Perhaps it's worth a test run to check its functionality?

I wouldn't trust any component in that picture to be safe.
I'd leave the heat exchanger alone if the leak could be fixed without opening it up, just because it's a pain to get it back together leak free with the ports pointing the right direction. If you do have to open the heat exchanger, then it turns into stripping the whole machine down to parts and cleaning/descaling everything.
I'd throw away the safety switch. I'd remove the safety valve clean it, force the face off of the seat with a blunt rod, let it reseat and test to see if it's perfectly sealed, and replace it if not.
I'd test all the wires for flexibility, any that crack their insulation when bent, I'd cut back or replace. I'd replace any loose fastons and boots.

Marcelnl wrote:crocus cloth??

crocus cloth, noun: cloth that has finely divided ferric oxide glued to one side and is used for fine abrading or polishing (Webster)

aha,like scotcbrite green and red

thanks for explaining!

JRising wrote:I wouldn't trust any component in that picture to be safe.
I'd leave the heat exchanger alone if the leak could be fixed without opening it up, just because it's a pain to get it back together leak free with the ports pointing the right direction. If you do have to open the heat exchanger, then it turns into stripping the whole machine down to parts and cleaning/descaling everything.
I'd throw away the safety switch. I'd remove the safety valve clean it, force the face off of the seat with a blunt rod, let it reseat and test to see if it's perfectly sealed, and replace it if not.
I'd test all the wires for flexibility, any that crack their insulation when bent, I'd cut back or replace. I'd replace any loose fastons and boots.

fully agree, repair the obvious issue thinking you're done to only find yourself facing the next one in days....there are a few potential problems you do not want to discover the hard way.

JRising wrote: ...I'd throw away the safety switch. I'd remove the safety valve clean it, force the face off of the seat with a blunt rod, let it reseat and test to see if it's perfectly sealed, and replace it if not...

I've already taken apart everything and cleaned/descaled it. So somehow I'll need to get it back However, I anticipate challenges aligning all the ports correctly given the bent pipes and limited wiggle room. There must be an optimal sequence for reassembling everything. I assume I can only check for leaks once the machine is fully reassembled. If any leaks are detected, it seems I'll be revisiting the entire process...

When you mention "Safety switch", are you referencing the 160˚Quick Mill Safety limit thermostat?

And concerning your advice for the "safety valve", I don't quite understand. Are you referring to the overpressure valve? I attempted to unscrew its top, but it's held in place by a spring. Could you specify which component you're discussing?

SwedishEspresso wrote:
When you mention "Safety switch", are you referencing the 160˚Quick Mill Safety limit thermostat?

And concerning your advice for the "safety valve", I don't quite understand. Are you referring to the overpressure valve? I attempted to unscrew its top, but it's held in place by a spring. Could you specify which component you're discussing?

Yes and yes.
No. Don't alter or mess around with the safety valve. Don't ever mess with a safety valve if you can not re-calibrate it. Simply test it and replace it if it's not perfect.