A few comments
Immersion heaters are exactly what the second element circuit is designed for. I have had some issues getting 40 litres to boil vigorously and have. A 2400w immersion heater and it gets it going. Be aware that immersion elements are high density heat elements and you may experience some burning around the element so keep an eye out.
As far as using "extension cords" in the special plugs we used in the controller. Most extension cords are rated for 10amps and that is on a good day with the cord unraveled and in clear air etc. they will not be 2.5mm copper. If you choose to use an extension cable then at least go for a quality 15a one and keep the length to a minimum. No matter how good quality the cable is if you draw a big current the cable will have voltage drop and will get hot.
I would probably suggest buying extras from ebay or Lael.
Anyone with serious issues with their controllers like relay not switching or display scrambling or other weirdness, PM me or Lael and we can sort out some repairs or replacements.
I will stress that you must run through the setup and enter values etc or it will not work correctly.
I am interested to hear what PID settings you are using. Would need to know the settings you use plus pot volume, element wattage, temp sensor position etc
I had the same issue with getting close but never actually hitting the temp and spent hours getting it to work with a live wort, still drinking the beer though.
James
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