Protecting Your RV Plumbing From Sudden Southeast Texas Freezes

If you live in Montgomery County, you know that our winter weather does not follow a neat schedule. We can have a week of sunny, 75-degree days that feel perfect for camping at Lake Conroe, followed immediately by a sharp Canadian cold front that drops temperatures below freezing in a matter of hours.

Because our winters are generally mild, many local RV owners do not think about winterizing until the local news starts warning about an incoming hard freeze. By then, it is often too late to prevent damage. When water freezes, it expands by about nine percent. In a confined space like your RV's plumbing system, that expansion has to go somewhere. The result is usually cracked plastic fittings, split PEX lines, and ruined water heaters.

As a mobile RV technician driving my converted ambulance to service calls from Willis down to Spring, I see the aftermath of these sudden freezes every year. Here is a practical, straightforward guide to protecting your RV's plumbing before the cold weather hits.

The Weak Points in Your RV Plumbing

Modern RVs mostly use PEX tubing for water lines. PEX is relatively resilient and can expand slightly without splitting, but the plastic elbow fittings, T-connectors, and threaded connections behind your cabinets are highly vulnerable.

The single most common freeze failure I encounter is the plastic water pump housing. Even a small amount of water left inside the pump head will freeze, cracking the housing and causing a major leak the next time you turn the system on. Other high-risk areas include the outdoor shower assembly, the city water inlet check valve, and the toilet valve. Because these components are often close to the exterior walls of the rig, they freeze first.

To Blow Out or to Use Antifreeze?

There are two main methods for winterizing an RV plumbing system: blowing the lines out with compressed air, or filling them with non-toxic RV antifreeze.

Blowing out the lines is a good option if you plan to use the RV occasionally during the winter. To do this safely, you need an air compressor with a pressure regulator. Never pump unregulated air into your RV lines; keep the pressure set between 30 and 40 PSI to avoid blowing out joints. You connect the compressor to the city water inlet using a blowout plug, open one faucet at a time starting with the closest one, and let the air push the water out until only mist or air emerges.

If your RV is going into storage in Willis, Magnolia, or Huntsville until spring, using pink RV antifreeze is the safer, more thorough method. It ensures that any small pockets of water left in low spots or inside the water pump are neutralized. Never use automotive antifreeze; you must use non-toxic, propylene glycol-based RV antifreeze.

The Water Heater Bypass is Crucial

Before you introduce any antifreeze into your system, you must bypass and drain your water heater. If you do not bypass it, you will waste six to ten gallons of antifreeze filling the heater tank before it ever reaches your hot water lines.

Locate the back of your water heater, which is usually accessed through an interior cabinet or under a bed. Turn the bypass valves to divert water away from the tank. Once bypassed, go outside, remove the drain plug (or anode rod if you have a Suburban heater), and open the pressure relief valve to let the tank drain completely. Leave the plug out for the winter.

Don't Forget the Low-Point Drains and Traps

Your RV has low-point drains that extend through the underbelly of the rig. Open these valves to let gravity do most of the work draining the system before you blow the lines or pump antifreeze.

Once the lines are cleared or filled with pink antifreeze, address the drains. Pour about a cup of RV antifreeze down every drain trap—the kitchen sink, the bathroom sink, and the shower. This displaces the water in the P-traps so they do not crack. Finally, flush some antifreeze into the toilet and leave a small amount sitting on top of the rubber seal to keep it from drying out and cracking.

Getting Professional Help in Montgomery County

If you are pressed for time, lack the tools, or simply want to ensure your rig is fully protected before a hard freeze hits, I can help. I bring my mobile shop directly to your driveway, storage lot, or campsite anywhere in Conroe, Montgomery, The Woodlands, or the surrounding areas to winterize your system or pressure-test your lines for existing leaks.

If you need practical, reliable RV plumbing service, call RV Paramedic at (936) 727-3066.