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PID Controller
Electronic temperature controller that holds boiler temp to ±0.5 °C by reading a probe and pulsing the element via a relay or SSR.
Category: Boilers & Heating
A Proportional-Integral-Derivative temperature controller — an electronic circuit that holds a boiler temperature stable to within fractions of a degree, by modulating heating element power based on real-time temperature readings.
Why it matters — A PID replaces the older mechanical pressurestat (pstat). It produces dramatically more stable temperatures, faster recovery between shots, and the ability to dial in to specific target temperatures for different coffees.
Good to know
- Standard on most prosumer and commercial machines made since around 2015. Older machines can usually be retrofitted with aftermarket PIDs.
- A well-tuned PID holds temperature within ±0.5 °C; a poorly tuned one swings several degrees and feels worse than a plain pstat.