Maretron Vacuum Switch

The Maretron Vacuum Switch (model VS-07.OHG) is a precision diagnostic sensor designed to detect excessive vacuum conditions in marine fuel systems. When vacuum exceeds 7 inches of mercury (3.4 PSI or 0.237 bar), this switch triggers an alert, signaling that fuel filter blockage has reached a critical threshold requiring immediate attention. For boat operators managing fuel system integrity during extended offshore runs or remote cruising, this sensor provides the early warning necessary to prevent fuel starvation and engine shutdown.

The 7-inch Hg (mercury) detection threshold is calibrated to the vacuum level at which clogged filters begin to restrict fuel delivery and compromise engine performance. Rather than waiting for a fuel starvation emergency at sea, skippers can monitor this vacuum-sensing switch as part of routine engine instrumentation. Maretron's design integrates with existing marine electrical systems, allowing centralized fuel system monitoring alongside other critical engine parameters. At 0.2 lbs and compact dimensions of 6 x 2 x 6 inches, the vacuum switch mounts easily in engine compartments or console-mounted systems without adding bulk to already-tight marine installations.

This vacuum sensor is essential for recreational anglers, charter captains, and cruising boat owners who operate far from service facilities. Weekend fishermen benefit from the peace of mind of knowing fuel filter status before departing the inlet; serious offshore anglers use it as part of redundant fuel system monitoring to ensure mission-critical reliability during multi-day passages. The switch is equally valuable for boat owners performing routine preventive maintenance, providing objective data on when fuel filter replacement is genuinely needed rather than relying on guesswork.

Maretron vacuum switches are recognized within the marine electronics community for straightforward sensor logic and integration with broader marine monitoring systems. Proper fuel system diagnostics require accurate vacuum sensing—this switch delivers the sensitivity and repeatability that serious boat operators demand when managing engine systems thousands of miles from a fuel dock.