Camco 59023 Propane Gauge & Leak Detector, Type 1

Here's the thing about propane on a boat or in an RV. You can't see it, you can't smell a slow leak until it's already pooled in a locker, and running out mid-cook always seems to happen on a Sunday. The Camco 59023 Propane Gauge and Leak Detector tackles both problems with one small fitting that threads right into your propane line. It gives you a quick read on how much fuel you've got left, and it flags a leak before it becomes a real problem.

This one is built for the Type 1 connection, the ACME/OPD valve that's standard on every DOT propane cylinder made after 1995. So if you've bought a 20 lb grill bottle or a 30 lb RV tank in the last couple of decades, this threads right on by hand. No tools, no thread tape, no wrenching. The inlet is an ACME nut and the outlet is a female Prest-O-Lite (POL) fitting, so it sits between your tank and your regulator or grill hose and passes gas through while it does its job.

The gauge itself is color coded. Green means you're good, and as the tank drains the needle works its way down toward the red. It reads the vapor pressure inside the cylinder, so a couple of things are worth knowing. It's most accurate when the appliance isn't actively drawing and the tank's at a moderate temperature. On a hot afternoon the pressure climbs and the needle reads high, and on a cold morning it'll read low even with plenty of fuel left. Treat it as a strong low-level warning and a leak-check tool rather than a to-the-ounce fuel gauge, and it'll serve you well for years.

The leak detector is the part that earns its keep. Once it's installed and the tank valve is open, it watches the line for the slow seep that a hand-tight fitting or an aging O-ring can develop. That's exactly the kind of leak you'd never catch by nose in an open cockpit. A lot of boaters still do the monthly soapy-water test on the connections too, and that's smart, but having a detector inline means you're not relying on memory.

Safety is baked into the body. It's got thermal protection that shuts the flow down if there's a fire, and excess-flow protection that closes off the gas if a line breaks downstream, say a hose that chafes through against a bulkhead or gets crushed in a slide-out. Both are the kind of feature you hope never to need and are very glad to have the day you do.

Where does it fit best? Grill bottles, RV tanks, and boat propane lockers all work. On the water it pairs naturally with 20 to 30 lb aluminum cylinders, the sizes most galleys and cockpit grills run. Mount it vertically with the vent facing down so rain and spray can't work their way into the diaphragm. A horizontal install invites water where you don't want it. If your setup lives near an engine or exhaust that gets genuinely hot, route the pigtail so the fitting sits in a cooler spot, because sustained high heat can nudge the thermal shutoff.

Install is about as simple as propane gets. Close the tank valve, thread the ACME nut onto the cylinder by hand until it's snug and square, connect your regulator or grill hose to the POL outlet, then open the valve slowly. Opening slowly matters on quick-connect grills, because snapping the valve wide can trip the excess-flow protection and leave you wondering why nothing's flowing. If that happens, close the valve, wait a moment, and reopen gently. A little dielectric grease on the threads at the start of each season keeps the ACME nut from seizing, which is worth doing on any boat that lives in salt air.

For a first-time RV owner or a boater who just wants to stop guessing at the tank, this is one of those cheap-insurance upgrades that pays for itself the first time it catches a low tank before dinner or a seep before it becomes a scare. It's a Camco part, built to the same standard as the rest of their propane line, and it works with the tanks you already own.