How to Blow Out Water Lines in a Camper: A Complete Guide for RV Owners
Why Is Blowing Out Water Lines So Important?
Let me start with the obvious question: why should you care about blowing out your water lines in the first place? Well, imagine your camper’s plumbing system as the lifeblood of your vehicle. When winter temperatures drop, any water remaining in those lines will freeze solid. Frozen water expands, and that expansion creates tremendous pressure inside your pipes, faucets, and fixtures. The result? Cracked pipes, burst tanks, and damage that could cost you thousands of dollars to repair.
This isn’t just a problem for those living in arctic climates either. Even if you’re in a milder region, an unexpected cold snap can wreak havoc on unprotected water systems. That’s why most RV experts recommend blowing out your lines before the winter season arrives, regardless of where you live.
The Real Consequences of Skipping This Step
Have you ever thought about what happens when you leave water in your camper through a cold winter? Beyond the obvious pipe damage, you’re also risking damage to your water heater, water pump, and holding tanks. Some damage might not even show up until spring, making it difficult to pinpoint what went wrong. By then, you’ve already lost valuable time and money that could have been saved with a simple preventive procedure.
Gathering Your Tools and Equipment
Before you dive into the actual process, you’ll need to assemble some essential equipment. The good news is that you probably don’t need to spend a fortune on specialized gear. Let’s break down what you’ll actually need.
The Air Compressor: Your Most Important Tool
The centerpiece of your water line blowout operation is an air compressor. Now, here’s where many people make a mistake: you don’t need a massive industrial compressor. A modest air compressor with a tank capacity of 20 to 30 gallons should work perfectly fine for most residential campers. The pressure should be somewhere between 30 and 50 PSI—too much pressure can damage delicate fixtures, while too little won’t effectively remove all the water.
Why does the compressor need to be moderate in power? Think of it like washing dishes: using a fire hose will break your plates, but a gentle rinse won’t get them clean. Your camper’s plumbing is similar—it needs enough force to push out water, but not so much that you destroy what you’re trying to protect.
Additional Equipment You’ll Need
- An air blowout adapter kit (connects your compressor to your water system)
- Adjustable wrenches in various sizes
- Teflon tape for securing connections
- A bucket or basin to catch water
- Towels or rags for cleanup
- Safety glasses to protect your eyes
- Work gloves for grip and protection
- Your camper’s owner’s manual for reference
Preparing Your Camper for the Blowout Process
Now that you’ve gathered your equipment, it’s time to prepare your camper for the procedure. Think of this as the warm-up round before the main event—it makes everything else go much more smoothly.
Locating the Water Inlet and Connections
First things first: find your water inlet. This is typically located on the exterior of your camper and might be labeled clearly, or you might need to consult your owner’s manual. The water inlet is where you normally connect your fresh water hose when you’re at a campground. This is going to be your main connection point for the air compressor.
Disconnecting and Draining Initial Water
Before you attach the air compressor, disconnect any external water hoses and let any standing water drain out naturally. Open all your interior faucets—both hot and cold—and let them run until they stop producing water. This initial drainage removes the easy-to-access water and makes the actual blowout process more effective.
Don’t forget to open your shower valve and any outdoor shower connections you might have. Every water outlet needs to be opened so air can flow through freely.
Preparing Your Water Heater
Here’s something many first-timers overlook: your water heater needs special attention. Most RV water heaters have a drain plug on the bottom. Open this drain and let the water completely empty out. Some water heaters also have a pressure relief valve—you might want to slightly open this to allow air to escape more easily during the blowout process. Check your specific water heater model’s instructions, as procedures can vary.
The Step-by-Step Water Line Blowout Procedure
Now we’re getting to the meat of the process. Follow these steps carefully, and you’ll have your water lines blown out like a professional.
Step One: Connect Your Air Compressor
Take your air blowout adapter kit and screw it onto your camper’s water inlet. Make sure this connection is tight—you don’t want any air leaking out during the process. Then, connect your air compressor hose to the adapter. Double-check all connections before proceeding.
Step Two: Set Your Air Pressure
Before turning on the compressor, adjust the regulator to the appropriate pressure. As I mentioned earlier, 30 to 50 PSI is ideal for most camper plumbing systems. If you’re unsure about your specific system’s requirements, err on the side of lower pressure. You can always increase it gradually if needed.
Step Three: Start with Lower Pressure
Turn on the air compressor and begin at the lower end of your pressure range. Let the air flow through your system for a few minutes. You’ll likely hear a lot of sputtering, gurgling, and hissing—this is exactly what you want to hear. It means water is being forced out of your lines.
As the water exits through your open faucets and fixtures, you’ll see it spray out in increasingly violent bursts. This is normal and expected. This is why having a bucket and towels nearby is important!
Step Four: Work Through All Water Outlets
Don’t just sit back and watch the air flow. Systematically go through every single water outlet in your camper. Close one faucet and open the next, allowing compressed air to push through each line. Include your kitchen sink, bathroom sink, shower, toilet fill valve, and any exterior shower connections.
For each outlet, let the air flow for about 30 seconds to a minute. You’re aiming for that moment when the sputtering stops and you’re getting clean air with no water droplets at all.
Step Five: Address the Fresh Water Tank
If your camper has an exterior fresh water tank fill, you should blow air through this as well. This helps ensure any water in that tank’s inlet line is removed. The fresh water tank itself might still contain water, but we’ll address winterization procedures separately.
Step Six: Don’t Forget the Toilet System
Your RV toilet is unique—it’s a gravity-fed system that’s separate from your regular water supply. While the toilet tank itself might still contain water (which is actually fine because it’s typically filled with an antifreeze solution), you should still blow out the water line that feeds it. Open the toilet fill valve and let air flow through for about 30 seconds.
Safety Considerations and Important Precautions
Working with compressed air is generally safe, but there are some important precautions you should always follow. These aren’t just recommendations—they’re essential for protecting yourself and your equipment.
Always Wear Protective Gear
Even though you might think you don’t need safety glasses, I strongly encourage you to wear them. Water and debris shooting out of faucets at high velocity can cause eye injuries. Gloves also protect your hands from the force of the air and any sharp edges around connection points.
Never Exceed the Recommended Pressure
I can’t stress this enough: more pressure does not mean better results. Exceeding 50 PSI can damage your camper’s delicate plumbing fixtures, seals, and valves. Your RV plumbing system is designed for low-pressure operation, typically around 20 to 60 PSI in normal use. Compressed air at excessive pressures can cause permanent damage that’s expensive to repair.
Keep the Compressor in Good Condition
Make sure your air compressor has an inline moisture trap or filter. Compressed air often contains moisture and oil particles. These contaminants can damage your RV’s plumbing system if they’re introduced into it. A good quality compressor will have built-in safeguards, but it’s worth verifying before you begin.
Common Mistakes That People Make
I’ve seen plenty of RV owners make the same mistakes year after year. Let me share what I’ve learned so you can avoid these pitfalls.
Forgetting About Hidden Water Sources
Many campers have water lines in places you might not immediately think about. Outdoor shower lines, if-and-when connections, and auxiliary appliances like ice makers can all contain water. Missing these means water can freeze in unexpected places, potentially causing damage in areas you’re not monitoring.
Rushing Through the Process
Some people try to speed through the blowout procedure, only spending a few seconds on each outlet. This doesn’t give you enough time to ensure all water is removed. Set aside at least two to three hours for the complete process, depending on your camper’s size.
Skipping the Water Heater Drain
I mentioned this earlier, but it bears repeating: not properly draining your water heater is one of the most costly mistakes you can make. Your water heater is one of the most expensive components in your plumbing system, and freeze damage can easily cost over a thousand dollars to repair.
Ignoring the Owner’s Manual
Every camper is slightly different. Your specific model might have unique plumbing configurations or requirements. Consulting your owner’s manual before you start ensures you’re not missing any critical steps unique to your vehicle.
Troubleshooting Stubborn Water Lines
Sometimes, you’ll encounter water lines that seem reluctant to drain completely. Don’t worry—this is more common than you might think.
When Water Just Won’t Stop Coming Out
If you’re getting continuous water flow from a particular outlet even after several minutes of air pressure, you might have a low spot in the line where water pools. Try opening multiple fixtures simultaneously to increase the flow rate and pressure throughout the system. This can help push water out of these low spots.
Weak Air Pressure Issues
If your air compressor seems to be losing pressure midway through the process, it might be time to drain the moisture tank on your compressor. Air compressors accumulate water in their tanks, and when these fill up, they can’t maintain consistent pressure. A quick drain should solve this problem.
Loose Connections Causing Air Leaks
Even tiny air leaks at connection points can significantly reduce the effectiveness of your blowout. If you notice pressure dropping or sputtering that seems out of place, check all your connections. Tighten any loose fittings, and consider using a bit more Teflon tape to improve the seal.
What to Do After Blowing Out Your Lines
The blowout process isn’t the complete winterization story. There are additional steps you should take to fully protect your camper.
Adding RV Antifreeze to Your System
After blowing out your lines, many experts recommend running RV antifreeze through your plumbing system. This provides additional protection in case any water remains in the lines or in low spots you couldn’t reach with compressed air. Simply connect a bottle of RV antifreeze to your water inlet and let it flow through all your outlets until it comes out clear.
Why this extra step? Think of it as a safety net. While blowing out removes most water, antifreeze ensures that any remaining moisture won’t cause problems if temperatures drop unexpectedly.
Draining Your Freshwater Tank Completely
Your fresh water tank itself should be drained as part of winterization. Most tanks have a drain plug on the underside or rear. Open this valve and let all water drain into a bucket. A completely empty tank prevents any potential freeze damage to the tank’s walls or bottom seams.
Protecting Your Gray and Black Water Tanks
Your gray water tank (from sinks and showers) and black water tank (from the toilet) also need winterization. These typically require adding several gallons of RV antifreeze to prevent any remaining water from freezing. Follow your owner’s manual for the specific amounts recommended for your camper.
Maintaining Your System Throughout Winter
Once you’ve completed the blowout and winterization, your job isn’t entirely done. Proper storage and occasional checks will ensure your plumbing system stays in great shape.
Regular Inspection and Monitoring
Even though your lines are supposedly blown out and winterized, occasionally check your camper for any signs of problems. Look for any evidence of leaks or water intrusion, especially after particularly cold nights. Early detection of problems can save you significant repair costs.
Protecting Exposed Pipes and Connections
If your camper has any exposed water lines or connections on the exterior, consider wrapping them with insulation tape or foam pipe insulation. This extra layer of protection can prevent freeze damage even if water somehow remains in the lines.
De-Winterization: Getting Ready for Spring
When spring arrives and you’re ready to use your camper again, you’ll need to reverse the winterization process. This is just as important as the winterization itself.
Flushing Out the Antifreeze
When you’re ready to use your camper again, you’ll need to flush out all the RV antifreeze from your system. Connect your fresh water hose to the inlet and let water flow through every outlet until the water runs clear and you no longer smell the antifreeze. This might take 15 to 20 minutes of continuous water flow.
It’s crucial that you do this thoroughly. Leftover antifreeze can affect the taste of your water and potentially cause issues with your plumbing fixtures. Some people prefer to have their water system professionally flushed if they’re
