Storing a vehicle properly through winter

Vehicles deteriorate when they are not used, and habitation bodies deteriorate faster than base vehicles. The mechanisms are unremarkable: standing water, trapped humidity, discharged batteries and rodents. All four are manageable with a morning's work.

Drain everything

Fresh and waste tanks, water heater, pipework and the toilet flush tank. Leave taps in the mid position and drain valves open. A litre of water left in a pipe will split it, and the repair is disproportionate to the cause.

Manage humidity, not temperature

Ventilation beats sealing. Leave roof vents on their winter setting, prop cushions on edge so air moves behind them, and lift mattresses off bases. A small dehumidifier on a timer is worth its power consumption if you have mains access.

Batteries

Lead-acid batteries sulphate below roughly 12.4V and will not fully recover. Either leave a smart charger connected or remove the battery and charge it monthly. Lithium banks prefer to be stored at around half charge and disconnected.

Tyres and movement

Inflate to the upper recommended pressure and move the vehicle a quarter turn every six weeks if you can. Where that is impossible, accept flat-spotting as a minor cost and check for sidewall cracking in spring.

Before the first trip

Sanitise the fresh water system, test the gas system for pressure drop, and run the heater for twenty minutes before you need it. The first weekend of the season is the wrong time to discover a failed pump.