6 Best Plumbing System Bypass Kits For Winterizing Rv Water Lines
Protect your RV water lines from freezing with these 6 best plumbing system bypass kits. Find the perfect kit for your winterizing needs and shop our guide now.
The first frost of the season often signals the end of comfortable road travel and the beginning of essential RV maintenance. Failing to properly bypass your water heater before pumping antifreeze into the lines can result in six gallons of wasted chemical and a difficult, lingering smell in the tank. Installing a reliable bypass kit is the single most effective way to protect your plumbing system while simplifying your winterization routine.
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Camco 35953 Kit: Best for Easy Installation
The Camco 35953 is the gold standard for those who prefer a straightforward, no-nonsense setup. This kit is designed for DIYers who want to get the job done quickly without needing specialized plumbing experience or complex tools.
Its pre-assembled nature ensures that all necessary valves are positioned correctly, minimizing the chance of improper installation. The simple on-off orientation makes it incredibly easy to switch between normal operation and winterization mode once the season turns.
This is the perfect choice for the casual RVer who values time-efficiency above all else. If simplicity is the priority, look no further than this reliable, widely compatible option.
Valterra P23415LF: Best Lead-Free Option
Safety in the water supply is a non-negotiable factor for long-term RV living, especially when considering the longevity of components. The Valterra P23415LF stands out because it is constructed with lead-free materials, adhering to stringent standards for potable water safety.
Beyond health benefits, the build quality is noticeably more robust than generic plastic bypass valves found in older factory setups. The reinforced construction means it is less prone to cracking during high-pressure water surges or the vibrations common during travel.
Choose this kit if you are concerned about water quality or if you plan to upgrade your system to modern plumbing standards. It provides long-term peace of mind, making it a high-value investment for full-timers.
Flair-It PEX Bypass Kit: Best for PEX Lines
Many modern RVs utilize PEX tubing, and using an incompatible bypass kit can lead to leaks at the connection points. The Flair-It PEX Bypass Kit is specifically engineered for these systems, utilizing a compression-style fitting that eliminates the need for expensive PEX crimping tools.
The magic of the Flair-It system is how it locks onto the tubing, ensuring a watertight seal that resists the pressures of typical RV water pumps. It feels incredibly secure, which is essential for plumbing located in hidden, inaccessible wall cavities.
If your RV is already plumbed with PEX, this is the most logical choice. It saves the hassle of sourcing crimp rings and avoids the potential for leaks inherent in makeshift adapters.
SHURflo Pump Converter: Best Pump-Mounted Kit
Some bypass systems are designed to go at the water heater, but the SHURflo Pump Converter focuses on the water source itself. By mounting directly to the intake side of the water pump, this kit allows you to draw RV antifreeze directly from a jug into the plumbing lines.
This eliminates the need to pour antifreeze into the freshwater tank, a process that can take days of flushing to fully remove in the spring. It is a cleaner, more professional way to circulate winterization fluid through every faucet and showerhead in the rig.
This is the ultimate convenience tool for those who winterize their rigs every single year. It is highly recommended for anyone who hates the lingering taste of antifreeze in their primary water tank.
Camco Hand Pump Kit: Best Budget Solution
For the occasional traveler or those with a very tight budget, the Camco Hand Pump Kit is a functional, low-cost alternative to a permanent bypass manifold. It works by manually forcing antifreeze through the city water inlet, bypassing the need for internal plumbing modifications.
While it is slower and requires more physical effort than a hard-plumbed valve, it does the job perfectly for smaller trailers or pop-ups. It is simple to store and requires zero installation time, which is a major advantage for those with limited space.
This kit is not the best choice for frequent travelers or large motorhomes with complex plumbing. However, it is an excellent “Plan B” or entry-level solution for those who aren’t ready to commit to a permanent installation.
RecPro All-in-One Kit: Best Universal Fit
The RecPro All-in-One Kit is designed to address the headache of finding the right fittings for an older or custom-built RV. It includes a variety of adapters and high-quality valves that cover most standard plumbing configurations found in the RV industry.
The versatility of this kit makes it a favorite for those renovating older units where original documentation is missing. It provides a comprehensive solution that prevents the need for multiple trips to the hardware store mid-project.
If you are dealing with a non-standard plumbing setup or simply want to ensure you have every adapter necessary to finish the job in one go, this is the solution. It is the most robust and flexible kit on this list.
How to Choose the Right Bypass Kit for Your RV
Choosing the right kit requires assessing your current setup rather than just looking at the features of the device. Start by checking your water heater’s accessibility; if it is behind a wall, a kit with longer, flexible hoses will make your life much easier.
Consider these key factors before purchasing: * Tubing Size: Ensure your lines are standard 1/2-inch PEX or reinforced hose. * Valve Type: Brass valves are generally more durable than plastic ones but carry a higher price tag. * Space Constraints: Measure the depth of the cabinet near your water heater to ensure the kit fits without kinking the lines. * Ease of Access: If the area is tight, prioritize a kit with easy-to-reach handles.
Avoid buying the cheapest option available if you plan on living in your RV during the shoulder seasons. Cold temperatures make brittle, low-quality plastic prone to failure, which is the last thing you want when parked in freezing weather.
Step-by-Step Bypass Kit Installation Guide
- Depressurize the System: Turn off the water pump and open all faucets to bleed out pressure.
- Drain the Water Heater: Locate the drain plug on the exterior of the water heater and empty the tank completely.
- Connect the Bypass: Shut off the inlet and outlet lines leading to the water heater, then install your bypass kit according to the manufacturer’s instructions.
- Test for Leaks: Close the bypass valves, turn the pump back on, and check every connection for slow drips.
- Set to Winterize: Move the valves to the “Bypass” position so antifreeze is directed around the tank rather than into it.
Consistency is key during this process. Always verify that the valves are in the correct position before you begin pumping antifreeze through the lines, as incorrect positioning can lead to a messy and costly mistake.
Common Bypass Installation Mistakes to Avoid
The most frequent error is neglecting to bypass the water heater entirely, which leads to filling the tank with antifreeze. This is not only a waste of product but also ruins the tank’s anode rod, which can be expensive to replace.
Another common oversight is failing to properly secure the hoses after installation. RVs vibrate constantly while in transit, so use zip ties or pipe clamps to keep lines from rubbing against sharp metal edges or vibrating loose at the fittings.
Finally, never over-tighten plastic threaded fittings. If they are leaking, a quarter-turn is usually enough; excessive force can crack the plastic threads and cause a failure later down the road.
Beyond the Bypass: Your Winterizing Checklist
A bypass kit is only one piece of the winterization puzzle. Before you consider the job finished, perform these critical tasks to ensure your rig makes it through the cold months safely: * Drain the Low Point Drains: Open these valves to empty all the water trapped in the lowest parts of your plumbing system. * Empty the Fresh Water Tank: Gravity-drain the tank and open the pump intake to clear the final few ounces. * P-Trap Protection: Pour a small amount of non-toxic RV antifreeze down every sink and shower drain to protect the P-traps. * Exterior Port Clearance: Don’t forget to blow out the city water connection and the outdoor shower if your unit is equipped with one.
Winterizing is an essential ritual that ensures your home-on-wheels remains in top condition for years to come. By treating this process as a standard maintenance chore rather than an inconvenience, you protect your investment and ensure a stress-free start to your next travel season.
Frequently Asked Questions (FAQs)
What is a plumbing system bypass kit for winterizing RV water lines?
An RV plumbing system bypass kit is a valve assembly that routes water or antifreeze around appliances like water heaters and water pumps during winterization. Most kits feature one, two, or three brass or plastic directional valves and flexible hose sections. Installing this setup prevents non-toxic RV antifreeze from filling the 6- to 10-gallon water heater tank, directing the fluid straight into the active plumbing lines instead. For winterizing, this simple plumbing modification preserves your heater tank while protecting all supply pipes from freezing fractures.
What does an RV water pump winterizing converter kit do?
A water pump winterizing bypass kit connects directly to the RV water pump inlet to siphon antifreeze straight from the jug into your plumbing lines. Instead of pouring gallons of antifreeze into the fresh water holding tank, this brass or plastic valve switches the suction source using a clear siphon hose. Once you switch the valve and turn on the onboard 12-volt pump, it pressurizes your plumbing system with antifreeze without contaminating your potable water tank.
How do I install a three-valve bypass kit on an RV water heater?
Install a three-valve bypass kit by shutting off your RV water supply, draining the water heater tank completely, and disconnecting both the cold inlet and hot outlet lines. Wrap Teflon tape around the tank’s male pipe threads, then thread the kit’s inlet and outlet valves onto the tank connections using an adjustable wrench. Connect the bypass bridge pipe between the two valves, reattach the RV plumbing lines, and tighten all compression nuts by hand plus a quarter turn to prevent leaks before testing under pressure.
How do you winterize RV water lines using a winterizing bypass valve?
Winterize RV water lines by closing the bypass valves leading to the water heater tank and opening the bypass valve connecting the hot and cold lines. Next, open your pump converter valve and submerge the siphon hose into a gallon of propylene glycol antifreeze. Turn on the RV water pump, then open each faucet, showerhead, and low point drain one by one until solid pink fluid flows steadily from every fixture. Finally, flush the toilet until pink fluid reaches the black tank.
Brass vs plastic RV plumbing bypass valves: which material is better?
Brass bypass valves are generally better than plastic valves because brass resists cross-threading, handles vibration during travel, and withstands seasonal freezing stress without cracking. Plastic nylon or ABS kits cost between $10 and $20 and resist chemical corrosion, but their threads strip easily under torque. Lead-free brass kits cost $25 to $45, provide tighter seals at standard half-inch NPT fittings, and last significantly longer in sub-zero storage climates. Choose brass if you frequently camp in freezing weather.
How much RV antifreeze does a water heater bypass kit save each winter?
RV water heater bypass kits save between six and ten gallons of antifreeze every winterization cycle by sealing off the water heater reservoir. Standard RV water heaters hold 6, 10, or 12 gallons of liquid. Without a bypass kit, you must fill that entire reservoir before fluid reaches your kitchen and bathroom faucets. At an average cost of $4 to $7 per gallon of RV-rated antifreeze, a bypass kit pays for itself in just one or two winter storage seasons.
What happens if you forget to turn the bypass valve when winterizing an RV?
Forgetting to turn your bypass valve causes several gallons of RV antifreeze to flood your water heater tank instead of shielding your plumbing lines. This mistake wastes expensive antifreeze, leaves far plumbing lines empty or filled with freezing water, and can taint your hot water with residual smells for months. If you realize the mistake immediately, drain the water heater tank using the exterior nylon drain plug, switch the bypass valve to the bypass position, and pump fresh antifreeze through the fixtures.
Is installing an RV plumbing bypass kit worth the money for older campers?
Buying and installing a plumbing bypass kit is completely worth the cost for older campers that lack factory-installed winterizing valves. Older travel trailers often require owners to blow lines with compressed air or use excessive gallons of antifreeze every fall. For an initial investment of $15 to $35 and roughly 30 minutes of labor, a bypass kit speeds up annual maintenance, prevents burst PEX pipes, and reduces long-term plumbing repair bills across the RV life.
