Tridicators (Boiler Gauges)

Tridicators from Marsh Instruments, also known as boiler gauges, are designed to indicate pressure in psi and altitude for pools and spas in feet of H2O, as well as in units of Fahrenheit or Celsius (°F and °C), making them suitable for use in hot water heating systems applications. Tridicators  Models are available in dial sizes of 2-1⁄2″ and 3-1⁄2″ and with three available pressure ranges. All Tridicators feature a set hand for setting desired pressure and altitude of the installation. Typical applications for Tridicators include hot water boilers, heated pools, spas and hot tubs.



  • Dial sizes of 2-1⁄2″ and 3-1⁄2″
  • Three available pressure ranges
  • Back or bottom mounting
  • Rotatable set pointer
  • Rugged construction
  • Tri-color dial
  • Hot water heating systems
  • Hot water boilers
  • Pools and spas
  • Any industrial or OEM application requiring fast and accurate temperature indication