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Tecmark Hydroquip Adjustable Pressure Switch - Universal - 1/8" NPT - 3902 3903

$56.00 $95.00
Tax included Shipping calculated at checkout.


Tecmark / Hydroquip Spa Heater Pressure Switch 3903-DF, 3902, 3903, 34-0178 1Amp SPST 1.5PSI for spa equipment and heaters. This is a very common pressure switch used by Balboa, Gecko, Davey, Spa-Quip, Spa Builders, HydroQuip, Pentair and others. Usually found near the heater assembly. They were originally branded as Tecmark, but may also be labelled Hydroquip now.


  • 1-5 psi 7-35kpa adjustable SPST
  • Found in a large number of spa and pool heaters
  • On/off device that controls heater operation
  • Utilises a diaphragm to sense water pressure. This closes a switch.
  • 1/8" NPT Thread rated to 1A. Fits most spa electric heaters.
  • Has two Spade connectors
  • 3903 Replaces 3902


3902 - 1Amp, 1-5psi Adjustable, 1/8" NPT 3903 - 1Amp, 1-5psi Adjustable, 1/8" NPT3903-BP 3Amp, PSI Factory Set Non-Adjustable, 1/8" NPT 3903-DF 1Amp, 1.5psi fixed, 1/8" NPT, MH26414, 3903-EECS, A2F / 0517, 34-0178

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