Skipping RV winterization might feel harmless, especially in a mild fall or in a region where hard freezes are rare. But one night is all it takes. Water left in an unwinterized plumbing system freezes when the temperature drops, expands as it turns to ice, and causes damage. Often, that damage isn’t visible until the spring, and then the repairs can be costly.
What Happens If You Don’t Winterize Your RV?
The scope of damage from a single freeze event can range from a single cracked fitting to a cascade of failed components, combined with undetected water intrusion into your flooring and cabinetry. The rest of this article breaks down what happens to each component if you don’t winterize, and how much it costs to fix.
Burst and Cracked Water Lines
Most modern RVs use PEX tubing, which is flexible enough to expand somewhat as water turns to ice. But the weak points are the rigid brass or plastic fittings at every joint, elbow, and connection point in the system.
When water freezes and expands inside those fittings, they often develop a hairline crack that holds up when the system isn’t pressurized but causes an issue immediately when the water pump is turned on or a city water connection is hooked up. This is why burst and cracked water lines can go undetected. The fitting looks intact, and the line holds shape until the system is pressurized and water appears where you don’t want it.
Where damage is most likely to occur:
- Low-point drain connections, where fittings are close to unheated exterior surfaces
- The water pump inlet and outlet connections
- Fittings in unheated underbelly runs, particularly near slide-out mechanisms
- Any line running close to an exterior wall in a portion of the RV without a heated underbelly
Water Heater Damage
The water heater is the most expensive plumbing appliance that freeze damage can destroy. A standard six or 10-gallon RV water heater tank retains water even after normal use. If you skip critical steps when draining the water heater during winterization (more on the winterizing process in a link at the bottom), residual water left in the tank can freeze, expand, and crack the tank. This kind of damage requires full water heater tank replacement.
A crack won’t become apparent until the system is running in the spring. Symptoms include a lack of hot water production caused by dislodged internal plastic components in the check valve, water pooling near the exterior water heater compartment door, rust staining or mineral deposits around the drain port, or a weeping pressure relief valve.
Tankless water heaters don’t have a vulnerable reservoir tank like standard models, but they retain water in the heat exchanger and mixing reservoir, which can be damaged when retained water freezes and expands. Always follow your tankless water heater manufacturer’s specific instructions recommending (or advising against) adding antifreeze when winterizing.
For a full walkthrough of the process, see our guide to winterizing an RV tankless water heater.
Water Pump Failure
Your water pump’s housing is typically made of rigid plastic or cast metal and cannot flex under expansion pressure. A freeze event can shatter a pump housing because the water inside the pump has nowhere to go as it expands. The internal mechanism that pressurizes the water, known as the impeller, is similarly vulnerable, even if the housing doesn’t crack. Additionally, the nylon pump valve assemblies can stretch even if the pump frosts, but doesn’t freeze hard.
How damage presents in spring:
- The pump runs but produces little or no water pressure.
- The pump makes grinding, rattling, or high-pitched sounds on startup that weren’t present before storage.
- The pump cycles on for a moment as the pressure bleeds off. The more frequent the cycling, the more severe the damage.
- The pump occasionally cycles on and off on its own.
- Visible cracks or splits in the pump body or at the inlet/outlet fittings, or a slight drip under the pump.
- The pump runs continuously without building or holding pressure.
Pumps mounted in unheated exterior compartments or in underbelly areas without thermal protection are significantly more vulnerable than pumps located inside the heated living space. If your pump is in an exposed location, it should be near the top of your pre-freeze checklist.
Technician Tip: The stretching of nylon water pump components mentioned above can also occur in sink faucets, toilet valves, and outdoor valves, such as tank or low-point drain valves. They aren’t broken and still function, but there will be a slow drip or a mixing of the hot and cold water.
How Much Does Freeze Damage Repair Cost?
Here’s a consolidated reference for freeze damage repair costs across the most common failure points:
| Component | Common Freeze Damage | Typical Repair Cost |
|---|---|---|
| Water lines (PEX fittings) | Cracked fittings, burst sections | $200 to $1,500 |
| Water lines – Secondary damage | Flooring, cabinetry, and walls from an undetected burst | Up to $6,000 |
| Water heater tank | Cracked tank, failed pressure relief | $600 to $1,500 |
| Water pump | Cracked housing, failed impeller | $100 to $600 |
| Faucets and fixtures | Cracked valve seats, failed seals | $500+ |
| Holding tank fittings | Cracked gate valves, split drain outlets | $200 to $800 |
Cost ranges reflect general industry repair data. Actual costs vary by location, RV type, and scope of damage. Contact a Camping World Service Center for a diagnosis and estimate.
Most of these repair costs depend on many factors, such as, but not limited to:
- How many fittings are affected and where they’re located
- How much secondary damage occurred before the leak was discovered
- The size and type of water heater on your RV
- The cost of replacement parts
- Labor rates in your specific region
The sooner you discover the damage, the quicker you can find a remedy and, in most cases, the lower your repair costs will be. In severe cases, water intrusion causes mold growth, further compounding the scope of repairs.
For a comparison of professional winterization costs vs the repair costs above, see our RV winterization cost guide.
Signs Your RV May Have Freeze Damage
If your RV was stored without being winterized, or if you’re not certain you winterized it properly before a freeze event, check these four things before you pressurize the system.
Low or no pressure when the pump runs. Turn on the water pump and check a nearby faucet. If you see little or no flow within the first 15-20 seconds, turn the pump off. Low or absent pressure is the first indicator of a cracked line, failed pump, or both.
Visible cracks, white mineral deposits, or rust staining at fittings and connections. Before pressurizing, walk through and visually inspect every accessible fitting, connection point, and the area around the water heater drain port. Freeze damage often leaves physical evidence, such as white mineral deposits where water leaked and evaporated, rust staining near metal components, or visible cracks at plastic fitting joints.
Water pooling in unexpected places when the system is first pressurized. If you do pressurize, stay with the system and check under every sink, in the water heater compartment, and in any basement storage areas. If you see water where it shouldn’t be, shut off the water immediately and locate the source before continuing.
Water heater that won’t heat, leaks at the relief valve, or shows rust at the drain port. If you see rust, persistent weeping from the relief valve, or any moisture around the heater compartment, have it inspected before use. These are indicators of tank damage that should be diagnosed before the unit is fired up. A water heater with a cracked tank may appear to function normally until it’s heated, at which point pressure and thermal expansion can make a manageable problem significantly worse.
How To Protect Your RV Before the First Freeze
Cost-wise, the math is fairly straightforward. The question isn’t really whether to winterize — it’s when, and whether to do it yourself or have a professional handle it. Learn when you should winterize based on your location, and then explore the pros and cons of professional vs DIY winterization.
If you suspect freeze damage has already occurred, don’t de-winterize or pressurize the system until it’s been inspected. A Camping World technician can diagnose freeze damage, recommend necessary repairs, and properly de-winterize the system once it is addressed.
Frequently Asked Questions
Owners must be aware that many RV insurance policies don’t cover freeze damage that results from failure to winterize. Instead, insurers classify it as preventable maintenance neglect rather than a sudden accidental loss. Some policies distinguish between freeze damage to a properly winterized RV (potentially covered as a sudden event) and freeze damage to an unwinterized one (excluded as neglect). The takeaway is to check your policy documents, and if you’re uncertain, call your insurer before you need to file a claim. Owners who can show a professional winterization service record, or detailed DIY records with receipts, are in a stronger position if a claim does arise.
Most freeze damage is repairable, though the cost varies. The key variable is time. Freeze damage caught at the start of de-winterization is almost always less expensive to address than damage discovered after the owner tries to use the RV and runs the pump or water heater. If you suspect freeze damage, have it inspected before operating the water system.
Technician Tip: Large, obvious leaks are often caught quickly before damage becomes extreme. It is the tiny, persistent leaks that often go unnoticed and lead to more severe secondary damage.
Any water remaining in the system after a partial winterization can cause damage. Partial winterization typically means one or more steps were missed. The RV’s plumbing system doesn’t distinguish between “partially winterized” and “not winterized”. Any pockets of water left behind will freeze at 32℉. If you’re uncertain whether your winterization was complete, have a certified technician verify before placing your RV into winter storage.
Before turning on the water pump or connecting to city water, perform a visual inspection. Check every accessible fitting and connection for visible cracking or mineral deposits, inspect the water heater compartment for signs of moisture or rust, and inspect the pump housing for visible damage. If anything looks suspicious, have it inspected by a technician. If everything looks clear, turn on the pump for 15 to 20 seconds. Check for pressure at fixtures and water appearing in unexpected places. Shut off the pump if there is no pressure or if you see any moisture.
Generally, standard homeowners’ insurance covers the dwelling and its contents, not a separately titled RV, even if the RV is stored on your property. RV-specific damage, including freeze damage to the plumbing system, falls under your RV insurance policy. Often, the actual freeze damage will be denied as neglect, but the secondary damages can be covered as a separate event.
Now that you understand the consequences, learn how to winterize an RV properly.
Have you dealt with RV freeze damage? Tell us what you found — and what it cost — in the comments below.
