What can hurt you on an RV

One coach packs LP, 120 V, a battery bank that can weld a wrench, hydraulics and a room that moves on its own. Know where each one bites and the habit that keeps it from biting you, before you open anything.

The short version

• Smell gas: no switches, no flame. Shut it off at the tank, get people out, open it up. Find the leak with solution or a detector, never a flame.
• 120 V: shore cord unplugged, generator off, inverter off. Then prove it dead with a meter you just checked on something live.
• Batteries: rings and watch off, glasses on. Negative off first and back on last. No sparks around a lead-acid bank that's been charging.
• Leveling jacks level. Nobody goes under a coach until it's on jack stands under the frame. Everyone clear before a slide or a jack moves.
• Roof, AC, water heater, generator: know if the roof is walkable, bleed the AC capacitor, let the water heater cool and take the pressure off, never run a generator in a closed bay.

LP: the one that can take the building with it

LP is heavier than air. A leak pools low, in the belly pan, on the bay floor, in a floor drain or a pit, and a spark from a light switch, a drop light or a battery lead is enough to light it. The coach's LP detector is mounted low for the same reason.

• Smell gas or hear the detector: put out any flame, don't touch light switches, fans or the shore cord, shut the valve at the tank or cylinder, get people out and open the doors.
• Shut the LP off at the tank before you open a line, a regulator or an appliance valve. Shutting the appliance off isn't enough.
• Find leaks with leak detection solution or an electronic detector. Never with a flame.
• Every LP job ends with a leak test of everything you touched. The lesson on leak testing has the procedure.

120 V: unplugged isn't the same as dead

Pulling the shore cord doesn't make the coach dead. A running generator, or an inverter with a transfer switch, can feed the same breaker panel and outlets from the batteries. And a pedestal or a shop cord can be wired wrong.

Before you open a 120 V box, a converter's AC side or an outlet, do it in this order:

1. Shore cord unplugged at the pedestal or shop outlet, with the plug where you can see it.
2. Generator off. On a coach with auto start, turn auto start off too.
3. Inverter off at its switch or remote panel, so it can't feed the outlets from the battery bank.
4. Check your meter on a known live outlet, test the circuit you're about to open, then check the meter on the live outlet again. Live, dead, live: a dead reading only counts if the meter just proved it works.

Careful: If anyone feels a tingle touching the coach, the door or the entry step, don't touch it again. Kill the breaker at the pedestal, then find out why with a meter before power goes back on. A lost ground can put line voltage on the whole body of the coach.

The battery bank

A 12 V bank won't shock you, but it will push hundreds of amps through a ring, a watch band or a wrench that bridges a terminal to the frame. That's enough to burn to the bone or blow a terminal apart. A lead-acid battery that's charging also gives off hydrogen.

• Rings, watch and bracelet off before you work near the batteries.
• Safety glasses on. Acid and a battery that pops both go for the eyes.
• Turn the converter or charger off before you pull battery cables.
• Negative off first, negative back on last. Then a wrench that touches the frame while you're on the positive terminal can't arc.
• No sparks or flame around a lead-acid bank that's charging or just came off the charger.
• Lithium packs have their own battery management and their own rules. Follow the maker's manual and never short the terminals.

Jacks, slides and anything that moves

Leveling jacks level. They don't hold a coach up for anyone to work under. Lippert's leveling manuals say the system isn't for service under the coach, changing tires included, and that the coach goes on jack stands front and rear before anyone works underneath. They also say to lift by the frame, never the axle or the suspension.

• Rated jack stands under the frame before you go under. Not blocks, not the leveling jacks, not the scissor stabilizers.
• Everyone and every tool clear before a slide or a jack moves. Lippert's manuals put it plainly: moving parts can pinch, crush or cut.
• A slide motor can move the room the moment you jump power to it to test. Know which way it will go and keep your hands out of the gap.
• Hydraulic lines can hold pressure with the pump off. Retract the jacks and relieve the pressure before you crack a fitting. A pinhole leak can push fluid through skin, and that's a trip to the hospital, not a bandage.

The roof, the AC, the water heater and the generator

These are the ones that catch techs who are in a hurry.

• Roof: find out if it's walkable before you step on it, stay on the framing, stay off skylights and vent lids, and use your shop's fall protection. Wet or frosty, stay off.
• Rooftop AC: the run capacitor can hold a charge with the power off. Discharge it before you put hands or tools on its terminals. Opening the sealed refrigerant system takes EPA Section 608 certification.
• Water heater: let it cool, shut off the water and take the pressure off at the relief valve before you pull the drain plug or the anode. That water can scald.
• Generator: never run it in a closed bay. Carbon monoxide has no smell. The muffler and exhaust stay hot long after it shuts down.

The habit

Before you open anything, say what's off: LP, shore, generator, inverter, and the batteries if you're working on them. Then prove it with the meter. It takes thirty seconds, every time, even on a quick one, and the tech next to you will start doing it too.

Shop tip

Say it out loud before you open a panel: shore off, generator off, inverter off, meter checked.

Where this comes from

• Lippert, Ground Control 3.0 Troubleshooting Guide (Forest River component manuals): the leveling system is for leveling only, not for service under the trailer such as changing tires; support the trailer with jack stands front and rear before troubleshooting; moving parts can pinch, crush or cut
• Lippert, Motorized Hydraulic Leveling with LCD Touchpad (4 point, 3 valve) Owner's Manual: do not go under the coach unless it is properly supported; jack stands at front and rear axles; lift by the frame, never the axle or suspension
• US EPA, Clean Air Act Section 608: technician certification to open refrigerant systems