When camping season ends and temperatures drop, your RV needs protection. The most critical task is winterizing the plumbing system. This involves draining all water and then adding non-toxic RV antifreeze to prevent pipes from bursting in freezing conditions. It’s a crucial process that prevents expensive, catastrophic damage and ensures your rig is safe for its long winter nap.
Why You Can’t Skip Winterizing Your RV
Before you begin, understand that winterizing isn’t just a recommendation—it’s essential insurance against the destructive power of ice. When water freezes, it expands by about 9%. This expansion generates enough force to split plastic pipes, crack fragile fittings, and destroy your water heater or pump.
These aren’t minor repairs. A single burst pipe can lead to widespread water damage, mold growth, complex plumbing repairs, and a significantly delayed start to your spring camping season. Think of winterizing as the final, most important maintenance task of the year.
The Core Goals of Winterization
The entire process boils down to a few key objectives. No matter which method you choose, the goal is always the same.
- Remove All Water: This means completely draining the fresh water tank, gray and black holding tanks, and especially the water heater.
- Protect the Entire Plumbing System: Every water line, faucet, toilet, and the water pump must be protected. You can either do this by blowing all the water out with compressed air or by replacing it with RV-specific antifreeze.
- Prepare for Secure Storage: Beyond plumbing, winterizing includes steps to protect your RV’s appliances, batteries, and exterior from pests and the elements while it’s stored.
A common rookie mistake is simply opening the low-point drains and assuming the job is done. Water always gets trapped in low sections of plumbing, P-traps under sinks, and inside the water pump itself. These hidden spots are where the most expensive freeze damage occurs.
Comparing RV Winterization Methods
Deciding between air and antifreeze? Here’s a quick comparison to help you choose the right method for your RV and confidence level.
| Method | Primary Goal | Pros | Cons |
|---|---|---|---|
| Compressed Air | To blow every last drop of water out of the lines, leaving them completely empty. | No antifreeze taste in spring, less expensive (no antifreeze to buy each year). | Requires an air compressor; can miss small water pockets if not done thoroughly. |
| Antifreeze | To replace all water in the plumbing system with non-toxic RV antifreeze. | Ensures every part of the system is protected; considered more foolproof for beginners. | Need to flush the system well in spring; ongoing cost of antifreeze. |
Ultimately, both methods work effectively when done correctly. The antifreeze method is often considered more reliable for beginners, while many experienced RVers prefer using compressed air.
This guide provides a clear roadmap to protect your investment. The absolute focus of winterizing is shielding that water system. It’s no surprise that industry data shows a staggering 60-70% of RV damage claims during winter are a direct result of poorly protected water lines.
Getting Your Winterization Gear in Order
There’s nothing worse than getting halfway through a job only to realize you’re missing a crucial tool. Before you touch a single valve, lay out all your supplies. Think of it as a pre-flight checklist. A little preparation now saves a ton of headaches later and ensures your RV winterization goes smoothly.
Essential Plumbing Supplies
First, let’s talk antifreeze. This is not the same product used in a car’s radiator—that is highly toxic. You must use a non-toxic product made specifically for RVs.
- RV-Specific Antifreeze: You’ll need 2-4 gallons of non-toxic, propylene glycol-based RV antifreeze. It’s typically pink for easy identification. Always buy an extra gallon—it’s cheap insurance against running out mid-job.
- Water Heater Bypass Kit: If your rig doesn’t already have one, this is a must-have. Without it, you’ll waste gallons of antifreeze filling your 6-to-10-gallon water heater tank, which is completely unnecessary.
- Anode Rod Wrench/Socket: You will need a 1-1/16 inch socket to remove the anode rod from most suburban water heaters. It’s a specific size that many standard socket sets don’t include. Have this ready before you start.
- Anode Rod or Plastic Plug: As you’ll be removing the anode rod to drain the water heater, it’s the perfect time for an inspection. If it’s more than 75% corroded, have a replacement ready for spring.
Key Tools for the Job
Next up, you’ll need a handful of tools to get into access panels, turn valves, and connect your antifreeze. Most of this is basic, but a couple of items are specialized.
A water pump converter kit (or a simple siphon hose) is a lifesaver. It allows your RV’s water pump to draw antifreeze straight from the jug. The alternative is to blow out the lines with compressed air first. For that, you’ll need an air compressor and a blowout plug that screws into your city water connection.
Here’s a quick rundown of the hand tools to have ready:
- An adjustable wrench or a socket set for the water heater drain plug.
- A cordless drill or screwdrivers for any access panels.
- Pliers for stubborn clamps or connections.
- A flashlight or headlamp for visibility in dark compartments.
My Pro Tip: Keep a roll of Teflon tape in your winterizing kit. It’s perfect for getting a good, leak-free seal on the water heater drain plug when you’re finished. This small detail prevents annoying drips and potential corrosion over the winter.
Prepping Your Tanks and Parking
Okay, last step before we get to the antifreeze. You need to deal with your holding tanks. You do not want to leave waste sitting in your black or gray tanks over the winter. Freezing can damage the tanks and valves, and the smell that greets you in the spring is unforgettable.
Head to an approved dump station and give both your black and gray water tanks a complete and thorough flush. Once they’re clean, park your RV on a slight incline before opening the freshwater drain and the low-point drains. This uses gravity to your advantage, helping coax every last drop of water out of the system. It’s a simple move that makes a big difference.
Draining Every Drop from Your RV Water System
This is where the real work begins. Your main goal here is to get every single drop of water out of your RV’s plumbing. This isn’t just a quick pull-the-plug-and-walk-away job; it’s a careful process to ensure no water is left hiding, ready to freeze, expand, and crack a pipe.
First, and this is a step you cannot skip, you must bypass the water heater. Your water heater is a tank holding anywhere from 6 to 10 gallons of water. If you don’t bypass it, your pump will try to fill that entire tank with expensive antifreeze. The tank doesn’t need antifreeze; it just needs to be empty.
This infographic gives you a quick visual of the first few moves, from draining the tanks to getting your tools ready for the antifreeze.
As you can see, a good winterization process is done in phases. You have to get all the water out before even thinking about adding antifreeze.
Find and Engage the Water Heater Bypass
Before you drain a single drop, make sure the water heater is off and has had plenty of time to cool down. Never drain a hot or pressurized tank—it’s a serious safety risk.
Once it’s cool, find the bypass valves. They’re usually on the back of the water heater, accessed through an inside cabinet, under a dinette seat, or behind a panel. Your owner’s manual can be a lifesaver here.
You’ll typically find one of three valve setups:
- Three-Valve System: The most common configuration. It has a cold water inlet valve, a hot water outlet valve, and a short connecting pipe with its own valve. To bypass, close the inlet and outlet valves and open the middle bypass valve.
- Two-Valve System: Simpler. Close both the inlet and outlet valves, and the system automatically reroutes the flow.
- One-Valve System: The easiest. A single lever is turned a quarter-turn to switch from normal mode to bypass.
With the bypass engaged, head outside to the water heater’s exterior access panel. Pop it open and carefully remove the drain plug. This is also the anode rod in most Suburban brand heaters. Be ready for a gush of water! Let it drain completely. This is the perfect time to inspect the anode rod; if it’s more than 75% corroded, you’ll want a new one for spring.
Opening the Floodgates: Low-Point Drains and Faucets
Now that the water heater is isolated and draining, it’s time to clear out the rest of the plumbing. Your next stop is the low-point drains. These are usually a pair of pipes, one for hot and one for cold, poking down from the underbelly of your rig. They might have little T-handle valves or simple screw-on caps.
Open them both up. Gravity is your best friend here, pulling water from the highest points of your system down and out.
Here’s a useful trick: I place a small, clean bucket under the drains. It’s a simple visual cue that helps me see exactly when the steady flow turns into a slow drip, confirming the bulk of the water is out. It’s an easy way to know you’re making real progress.
To get the water out faster and more completely, you need to break the vacuum in the lines. Head back inside your RV and open every single faucet—both the hot and cold sides. Don’t miss any of them:
- Kitchen sink
- Bathroom sink
- Indoor shower
- Toilet flush valve (hold it down for about 30 seconds)
- Any exterior shower or kitchen faucet
You should hear a gurgling sound as air enters the system, pushing the remaining water out of the low-point drains. That gurgle is the sound of success. Leave all the faucets open until the water stops flowing from the drains underneath. Once it’s just a slow drip, you can close up the low-point drains and all the faucets.
At this point, your tanks are empty, your water heater is bypassed and drained, and your lines are as empty as possible with gravity alone. You’ve set the stage perfectly for the next step—getting the antifreeze in.
Protecting Your Pipes with RV Antifreeze
With all the water drained, you’re ready for the final layer of protection. This is where the famous pink non-toxic RV antifreeze comes in. Pumping this solution through your pipes pushes out any stubborn water droplets left behind. It’s the critical step that ensures nothing can freeze, expand, and crack a line during a cold snap.
The goal is to methodically push antifreeze through every single water line until you see a steady pink flow from each faucet. When you see that pink, you know all the water is gone and your plumbing is safe for the winter.
Choosing Your Antifreeze Method
You have two main ways to get the antifreeze from the jug into your RV’s plumbing. Both work well, and your choice depends on your equipment and comfort level.
- Using the Onboard Water Pump: This is the most common method. You’ll need a water pump converter kit or a basic siphon hose that attaches to the inlet side of your pump. This lets the pump draw antifreeze straight from the gallon jug instead of your freshwater tank.
- Using an External Hand Pump: If you’d rather not connect to your RV’s pump, a simple hand pump is a great alternative. These connect directly to your city water inlet and let you manually pump the antifreeze into the system.
I’ve used both methods. The onboard pump is faster, but the hand pump is extremely simple and requires zero tools to connect. You can’t go wrong either way.
Crucial Safety Note: Only use propylene glycol-based RV antifreeze. Never use automotive antifreeze. The ethylene glycol in car products is highly toxic and will permanently contaminate your fresh water system. It will also destroy the rubber seals in your faucets and toilet.
Pumping Antifreeze Through the Lines
Once your pump method is set up, the next steps are the same. If using the siphoning method, turn on your RV’s water pump to start pressurizing the system with antifreeze. From there, it’s a methodical trip through your RV.
I always start at the faucet closest to the pump, which is usually the kitchen sink.
- First, open the cold water tap. Let it run until the liquid coming out is a solid, bubble-free pink.
- Close the cold tap, then open the hot water tap. Wait for that same solid pink flow.
- Once both sides are done, shut the faucet off and move to the next one.
Repeat this exact process—cold first, then hot—for every single water outlet in your rig. It’s easy to forget one, so make a checklist.
Don’t miss these spots:
- Bathroom sink
- Indoor shower (run it through the shower wand, too!)
- Outdoor shower or kitchen
- Toilet flush valve (hold it down until you see pink antifreeze filling the bowl)
- Bonus Tip: Pour about a cup of antifreeze down each sink drain and the shower drain to fill the P-traps. This prevents any trapped water from freezing and protects the traps from sewer gas.
By working from the closest faucet to the furthest, you ensure the entire system gets filled efficiently. Keep an eye on your antifreeze jug; you’ll likely need to swap to a fresh one partway through.
How Much Antifreeze Do I Need?
This is one of the most common questions. The answer depends on the size and complexity of your rig’s plumbing, but a good rule of thumb can be followed.
For most travel trailers, fifth wheels, and Class C motorhomes, 2 to 3 gallons is usually sufficient. For larger Class A motorhomes or those with appliances like a washing machine or ice maker, you might need 4 gallons or more. I always buy one extra gallon just in case—it’s cheap peace of mind.
Once you see pink antifreeze flowing from the very last fixture, you’re done! Shut off the water pump and close your antifreeze jugs. You can now rest easy knowing your entire plumbing system is protected.
Final Steps for Total Winter Protection
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Getting antifreeze in the lines is the biggest part of the job, but these next steps are what separate a decent winterization from a great one. These details ensure you return in the spring to a rig that’s ready to roll, not one that needs surprise repairs.
Let’s start with your RV’s battery. Leaving it connected is a recipe for a dead battery in the spring. A discharged battery can freeze and crack, leading to an expensive replacement.
The easiest option is to disconnect the negative terminal, which stops the slow parasitic drain. However, the best method for long-term storage is to remove the battery completely.
Take it home and store it somewhere warm and dry, like a garage or basement. Do not set it directly on a concrete floor, which can accelerate discharge. Place it on a piece of wood or plastic instead. To keep it healthy, connect it to a battery tender or a smart charger about once a month.
Prepping Appliances and Preventing Pests
Now, let’s head inside and deal with the appliances, starting with the fridge. Once it’s off, clear out all food. Give the interior a good wipe-down with a mild bleach or vinegar solution to prevent bacteria growth.
After it’s completely dry, prop the doors open. A small towel or a purpose-made latch works great. This is the single most important step to prevent musty smells and mildew.
Next up: unwanted guests. A stored RV looks like a five-star winter resort to rodents, and they can do incredible damage by chewing through wires and upholstery. The best defense is a good offense. Seal every possible entry point.
Grab a flashlight and do a slow walk around and under your rig. Look for any gaps around plumbing lines or wiring. Use steel wool or expanding spray foam to plug any hole you find. Even a dime-sized opening is an invitation for a mouse.
Securing the Exterior for Winter
The last piece of the puzzle is protecting your RV’s exterior. A good wash and wax is a great place to start. Removing road grime and dirt helps protect the finish from damage during long-term storage.
Your roof needs special attention. Get up there and carefully inspect all the seals around vents, skylights, and along the edges. Look for any cracks or gaps in the sealant. A tiny crack now can become a major leak when snow melts, leading to delamination or serious interior water damage. A quick touch-up with the proper RV sealant is time well spent.
Finally, consider a cover. It’s tempting to use a cheap tarp, but don’t. Tarps trap moisture, creating a perfect environment for mold and mildew. A quality, breathable RV cover is a much better investment. It protects from UV rays and sheds rain and snow, all while letting air circulate, ensuring your RV looks just as good in the spring.
Protecting your investment is always a smart move. In fact, even as new RV sales fluctuate, the market for products that help maintain and protect current vehicles stays strong.
Common Questions About Winterizing Your RV
Even after you’ve done this a few times, questions can arise. Getting it wrong can be costly, so here are straightforward answers to common queries.
Can I Just Use Compressed Air Instead of Antifreeze?
Yes, you can, and many people prefer this “blowout” method. You’ll need an air compressor and a special blowout plug that screws into your city water inlet. The key is to keep the pressure low—never go over 50 PSI—to avoid damaging your plumbing. From there, you go faucet by faucet, blowing all the water out of the lines.
The upside is no antifreeze taste in your water come spring and no annual cost for antifreeze.
The catch is that it’s not foolproof. A small pocket of water can hide in a low spot in a pipe or a valve. That tiny amount of water is all it takes to freeze and crack a fitting.
Personally, I prefer a “belt and suspenders” approach. I blow out the lines first to get them as dry as possible, then follow up with a gallon or two of antifreeze. This gives me total peace of mind that every inch of the plumbing is protected.
What If I Accidentally Pumped Antifreeze into My Water Heater?
First, don’t panic. This is the most common mistake newcomers make, and the good news is you haven’t broken anything. You’ve just wasted some antifreeze and created a cleanup job for yourself.
Getting it out is simple, just a little tedious.
- Open the exterior access panel for your water heater.
- Slowly and carefully remove the drain plug or anode rod. Be ready for all that pink antifreeze to come rushing out.
- Once it’s empty, reinstall the plug and fill the tank with fresh water.
- Drain it completely one more time.
You might need to repeat the fill-and-drain cycle two or three times to flush out all the residue. When you dewinterize, run the hot water taps for a few minutes to clear any last traces from the lines. It’s an annoying mistake, but it’s 100% fixable.
How Do I Dewinterize My RV in the Spring?
Getting your rig ready for camping season is much easier than putting it away. Your main jobs are to flush the antifreeze, sanitize the water system, and get all your appliances back online.
First, flush all the pink stuff out. Hook up to a city water connection or use your fresh tank and water pump. Open every faucet (hot and cold), one at a time, until the water runs completely clear with no foam. Don’t forget the toilet and any showers.
Next, get your water heater out of bypass mode. Reinstall the anode rod or drain plug. Turn the water on and let the tank fill completely—you’ll hear the gurgling stop when it’s full. Only after it’s full should you turn on the electric or propane heating elements. Firing up an empty tank will burn out the element in seconds.
The last, and most critical, step is sanitizing the whole system. Bacteria can grow in your water tank over the winter, so a good cleaning is a must.
- The standard recipe is 1/4 cup of household bleach for every 15 gallons your fresh tank holds.
- Mix the bleach with a gallon of water first, then pour it into your fresh tank. Fill the tank the rest of the way with water.
- Turn on your water pump and run each faucet until you smell the bleach, then shut them off.
- Let that solution sit in the tank and pipes for at least four hours; overnight is even better.
- Finally, drain the whole system and refill it with fresh water. Flush everything again until the bleach smell is gone.
For all your RV winterization needs, from antifreeze to water heater bypass kits, RVupgrades.com has you covered. With over 20,000 products and expert support, we make it easy to find exactly what you need to protect your investment. Shop our full selection of plumbing and maintenance supplies at https://www.rvupgradestore.com.
