Relatively speaking, propane is a fairly new fuel aboard boats. As recently as the 1970s, the majority of recreational boats relied on denatured alcohol, kerosene, or diesel for cooking and heating tasks. The downsides to those fuels included fussy pressure tanks and cantankerous burners that often wouldn’t work. That meant boat owners often spent more time trying to get their stove or heater to work than they actually used them.
Also known as liquefied petroleum gas (LPG), clean-burning propane changed all of that — no more hand-pumped pressure tanks or fiddling with clog-prone burners. But propane does have a couple of downsides. First of all, it’s highly volatile, meaning it takes only a small amount and a tiny spark to cause an explosion. Second, propane is heavier than air. That means any on-board gas leaks from storage tanks or supply lines can quickly settle to the lowest part of the boat, where the fumes are almost impossible to detect.
That shouldn’t scare you away from buying a boat that has propane, though. Despite the downsides, a propane system made of high-quality components, properly installed and maintained, can provide many years of safe and trouble-free cooking and heating. Here are some things to look for:
Lock it Up
Propane tanks should not be stored anywhere on a boat except in a dedicated propane locker. That locker should have a gasketed lid, vapor-tight bushings wherever any hoses pass through it, and a vent line installed at the bottom that discharges to an overboard through-hull fitting above the waterline. The idea is to contain any gas leaks in the tank’s supply plumbing, or the tank itself, and then vent that gas overboard, where it can safely dissipate. Without a self-contained locker, leaks can cause explosive propane gas to settle in the bilges of your boat—a recipe for disaster.
Shut it Off
The best way to prevent trouble between the tank locker and the stove is simply to close the propane tank valve when you’re not cooking or heating. If you tend to forget such things, you can install an electric solenoid valve after the regulator in the tank locker to give you a way to shut off gas flow remotely. Worried about the valve failing or staying open if the house battery dies? No worries, propane solenoids are designed to fail in the closed position.
Sniff it Out
Any boat equipped with a propane system should have a propane fume detector installed. Often referred to as “sniffers,” these devices use a sensor installed in the lowest possible part of the boat near possible leak sources, such as a stove or heater, to sniff out LPG fumes. While stoves and heaters today are equipped with thermocouple devices that shut down gas flow if a flame is extinguished, a propane detector can help smell out trouble from a leaky appliance connection before it turns into a potentially explosive problem. Some propane fume detector models will even shut off the gas supply at the tank via a solenoid when propane fumes are detected.
Line it Up
The supply lines (generally made of rubber hose) that carry pressurized propane gas from the tank to the appliances in your boat obviously need to be in tip-top shape, so make sure they are not cracked or worn, and are secured with cushioned stainless-steel hose clamps at regular intervals. Propane supply hoses must also be one continuous length from the tank all the way to the connection at the stove or heater. If you find a hose joined with a barb fitting and hose clamps at any point, remove the whole shooting match from the boat and buy a suitable-length, pre-made propane hose with flared connection ends from your marine shop.
While there are certainly more pieces and parts to a properly installed propane system that what we’ve listed here, making a check of these basic areas first can go a long way toward ensuring safe propane cooking and heating aboard.
A previous version of this article appeared on Boat Trader in October 2014, updated July 2017 and June 2020.