Recreational Vans

Water system winterization service

Why winterization matters for mobile water systems

Frozen water expands with surprising force, and that expansion targets the weakest link in a van or towable plumbing run. Poly lines can split, fittings can hairline crack, and threaded plastic can deform. Damage often hides behind panels until pressurized in spring, leading to slow leaks that soak insulation and subfloors. A proper water system winterization service prevents those failures by removing liquid water and protecting every cavity that could trap moisture.

Modern camper layouts include components beyond a simple tank and pump. Expect a diaphragm pump, accumulator, cartridge filters, UV sterilizers, tank sensors, a water heater or heat exchanger, and a city water inlet with an internal check valve. Each can retain small amounts of water, so attention to sequence and flow direction is critical. Grey and black systems also need protection at valves and P traps where residual water sits in the bend. Getting it right keeps potable plumbing safe and saves you from springtime mold remediation.

Methods used in a water system winterization service

Technicians commonly use two proven approaches. The first is a dry method that clears lines with regulated compressed air after draining tanks and water heaters. The second is a wet method that displaces water with non toxic RV antifreeze made with propylene glycol. Both aim to eliminate freezeable pockets while preserving seals and fixtures.

Compressed air blowout

With a blowout plug and a regulator set to conservative pressure, pros push air through the system while fixtures open one at a time. The key is patience and a consistent sequence that includes hot and cold lines, showers, sprayers, and toilet feeds. City water inlets and outside showers need direct attention since they often trap water behind check valves. Air-only methods do not leave taste or residue, and they work well in regions with occasional light freezes, provided every trap and appliance cavity is cleared.

Non toxic RV antifreeze

In colder climates or for complex layouts, propylene glycol antifreeze becomes the safety net. After bypassing the water heater, technicians draw the solution through the pump and into every fixture until a uniform color flows. This displaces remaining water and protects traps, valves, and the pump head. The formulation is food contact safe when labeled for potable systems and helps condition rubber seals during long storage.

Hybrid approach and common mistakes

A hybrid service clears lines with air first, then chases the system with a minimal antifreeze volume to guard hard to purge zones. Mistakes happen when low point drains are missed, filters are left in place, or a tankless heater is not properly bypassed. Another common oversight is the city water check valve, which can hold a small slug of water that cracks the body. Finally, P traps under sinks and showers must be filled with antifreeze even if the rest of the system is air only.

What professionals check beyond the basics

Effective winterization is more than pushing air or pink fluid. A technician evaluates the entire plumbing map: freshwater tank, fill and vent lines, pump orientation, accumulator location, and any tees that can hold water. They note material differences between PEX, reinforced vinyl, and quick connect fittings to set safe pressures and flow rates.

Water heaters need special care. Tank style units should be fully drained with anode or drain plug removed, then bypassed so antifreeze does not enter the tank. Tankless heaters and heat exchangers often include internal sensors and narrow passages that require manufacturer specific procedures. Ignoring those can lead to costly replacements even if the rest of the system is protected.

Appliance valves and accessories deserve attention too. Spray wands, bidet attachments, and rear outdoor showers can be overlooked. The toilet line and flush valve must show full protection. If your rig uses a macerator, pros ensure the pump case and discharge are secured against freezing. Lastly, the city inlet’s backflow components are verified clear or filled to spec.

Regional timing and storage considerations

The best time for a water system winterization service is before the first sustained freeze in your region. A single cold night might not do harm, but repeated cycles stress fittings and trap ice deep in runs. If you travel between climates, winterize for the coldest leg of your route. During storage, open cabinet doors around plumbing to reduce cold soaking, and remove or protect any treatment cartridges. In spring, a thorough flush, sanitization, and pressure test will return your potable system to service without off flavors.

Professional winterization for vans and towables

Vans pack a lot into tight spaces: cabinetry wrapped around plumbing, hidden low points, and appliances sharing warm and cold zones. That density rewards a trained eye. A professional service maps flow paths, protects seals, and respects material limits while moving quickly and cleanly. For towables and overland rigs, the same principles apply with added focus on exposed lines and exterior valves. The result is the same goal every time: a clean start in spring with no surprises and no repair bills.

A final note on safety. Only use propylene glycol products labeled for potable systems. Do not mix with automotive antifreeze. Pressure regulators, bypass valves, and proper sequencing matter more than how fast the job goes. Quality winterization is conservative, methodical, and documented so you know every fixture and line was addressed.

Strong builds deserve careful seasonal care. If you want a pro to handle it, choose a shop that understands adventure platforms, power integrations around plumbing, and modern heater configurations.

Protect your water system before the first hard freeze. OZK Customs services camper vans, overland builds, and towables in Northwest Arkansas with careful, system specific winterization that respects your layout and components. Submit the form to reserve your service slot and head into winter with total confidence.

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