• LH29-1001
  • Usually ships in 1-2 weeks



  • Contact type: (1) SPST reed
  • Pressure: 50 psi (3.44 bar)
  • Contact output: NC (opens on rise)
  • Process temp.: -40 to 221°F (-40 to 105°C)
  • Contact state: NC, Open on rise
  • Float material: Foamed polypropylene
  • Body material: Valox 420
  • Applications with limited space and corrosive liquids
  • Pivot pin: Stainless steel
  • Wire type: 2 conductor, #22 AWG
  • Wire length: 10’ (3.04m)
  • Wire jacket material: Halar jacketed
  • Contact rating: 30 watts
    • 240 VAC (0.14 amps resistive)
    • 120 VAC (0.28 amps resistive)
    • 120 VDC (0.07 amps resistive)
    • 24 VDC (0.28 amps resistive)


The Flowline LH29 Interstitial Leak Detection Switch provides reliable leak detection in and around secondary containment sumps and tanks with a 1A relay output. The flat body Valox leak sensor is ideal for placement in hard to reach interstitial areas with limited space. In the event of a leak, the foam polypropylene float will rise to signal the presence of unwanted liquid in the containment vessel. The leak detection switch is typically mounted flat on the bottom of the sump floor or secondary containment tank wall.

Additional features / benefits for the Flowline LH29 Interstitial Leak Detection Switch include:

  • Valox sensor body with PP float and Halar® jacketed cable for corrosive liquids
  • Flat, low profile sensor with minimal float rise for applications with limited space
  • Dry contact, normally closed reed switch opens to signal the presence of liquid
  • Easy to install
  • Ideal for double wall tanks or pipes
  • Used to signal the presence of liquid leaks or overflow in any containment area