ServiceNomad RV · Knowledge
Smell of Gas Inside RV
The smell of propane gas inside your RV is an emergency situation requiring immediate action. Propane is intentionally odorized with mercaptan (a chemical that smells like rotten eggs or sulfur) so leaks can be detected by smell. If you detect this odor, even faintly, treat it as a serious leak until proven otherwise. Propane is explosive in concentrations of 2.1% to 9.5% in air—a small leak in an enclosed RV can quickly reach dangerous levels.
Immediate Actions for Gas Smell
If you smell propane inside your RV: (1) Evacuate everyone immediately to a safe distance upwind. Do not waste time investigating or trying to find the leak. (2) Do not turn any lights, switches, or appliances on or off—even a small spark can ignite accumulated gas. (3) Do not use your cell phone inside the RV—the spark from pressing buttons or the battery connection can ignite gas. (4) Once everyone is out, shut off the propane supply at the tank(s) by turning the valve(s) clockwise to close. (5) Open windows and doors from outside if you can safely do so without entering the RV. (6) Do not re-enter until the RV has been thoroughly ventilated and the smell is completely gone. Call a propane technician or fire department to inspect the RV before turning the gas back on. The source of the leak must be found and repaired—never assume the smell will 'go away' on its own.
Common Sources of Gas Smell
Propane smells inside RVs most commonly come from: pilot lights that have blown out (leaving the gas valve open but unlit), stove burners turned on without ignition, loose fittings at appliance connections, failed propane regulators venting gas into the regulator compartment, cracked or aged propane hoses, or improper connections after tank refills. Even a stove knob bumped slightly 'on' can release enough gas to be detected within minutes in a closed RV. Less common but possible: propane line damage from rodents chewing, internal leaks in propane distribution piping behind walls, or failed appliance valves. A qualified technician will use a gas leak detector (electronic sniffer or soap solution) to trace the leak to its source.
Tank Valve and Regulator Issues
Sometimes the smell of propane comes from outside the RV near the propane tanks. Propane regulators have vent holes that release small amounts of gas during normal operation (pressure equalization). However, a failed regulator diaphragm can cause continuous venting, creating a strong smell near the tank compartment. If the smell is strongest outside and near the tanks, suspect the regulator. A technician will test the regulator's lock-up pressure and check for proper venting behavior. If the regulator is venting continuously or if the diaphragm is ruptured, the regulator must be replaced. Similarly, if tank valves are not fully closed or if the POL fitting (the brass connection between tank and regulator) is loose, gas will leak at the connection point.
After the Leak is Repaired
Once the leak has been repaired, the technician will test the entire propane system for leaks using a gas detector or soap solution on every fitting. They'll pressurize the system and verify no leaks exist before returning the RV to service. You should also test your propane detector to ensure it's functioning properly—this is your early-warning system for future leaks. After major propane work, the system may need to be purged of air before appliances will light properly. This involves opening appliance valves and allowing gas to push air out of the lines until you smell propane at the burner. Only then can appliances be safely lit.
⚠️ Safety Notes
- NEVER use open flames (matches, lighters) to search for propane leaks—use a gas detector or soap solution only.
- NEVER re-enter an RV that smells of propane until it has been fully ventilated and the leak source has been found and repaired by a qualified technician.
- Propane is heavier than air and will pool at floor level—the explosive concentration zone is where you walk and where ignition sources (appliances, switches) are located.
Can't fix it yourself?
Don't let a mechanical issue ruin your trip. Connect with vetted mobile RV technicians who can come to your location and get you back on the road.
Related Professional Services
Mobile RV Repair
On-site RV repair at your home, storage lot, or campsite so you don't have to move your rig.
RV Furnace Repair
Get your RV furnace lighting reliably so you have safe, consistent heat on cold nights.
RV Plumbing Repair
Fix leaks, water pump problems, toilets, and water heaters in your RV's plumbing system.