There are two ways to get the water out of an RV's plumbing before a freeze. You can blow it out with compressed air, or push RV antifreeze through the lines. Many owners do both: air for the supply lines, then antifreeze for the drain traps. This guide compares the two methods and the Camco parts each one needs, so you can buy the right kit once. For the full step-by-step, including draining and storage, see our RV winterizing checklist.
The two methods at a glance
| Blow-out (compressed air) | Antifreeze (pumped through the lines) | |
|---|---|---|
| What you need | A blow-out plug and an oil-less air compressor | RV antifreeze plus a hand pump kit or a pump converter kit |
| Consumables | None | RV antifreeze, every year |
| Spring start-up | Fill and run the water | Flush the antifreeze out of the lines first |
| Weak spot | Water can stay in low spots and traps if you rush it | Uses more antifreeze if the water heater isn't bypassed |
| Drain traps and toilet | Still need antifreeze poured in | Covered as you run each drain |
Method 1: blow out the lines with air
A blow-out plug threads into the RV's city water inlet so a compressor can push the water out of the supply lines. Camco's directions are the same for all three of its plugs: screw the plug into the city water inlet, open all drains and faucets, then connect an oil-less compressor and run it until all the lines are clear. An oil-less compressor keeps compressor oil out of the lines that carry your drinking water.
| Plug | Body | Connects to |
|---|---|---|
| Quick-Connect Brass Blow-Out Plug (36143) | Brass | A quick-connect air coupler |
| Brass Blow-Out Plug with Schrader Valve (36153) | Brass | A tire chuck |
| Plastic Blow-Out Plug with Schrader Valve (36133) | Black plastic | A tire chuck |
Pick the plug by the end of your compressor hose. Our answer page quick-connect or Schrader goes through the choice in more detail.
Keep the air pressure modest. Too much pressure can split a plastic fitting, so follow your RV maker's limit (our checklist uses 40–50 PSI). Then open each faucet one at a time, hot and cold, until only air comes out. Don't forget the outside shower and the toilet valve.
Best for: owners who already have a compressor, don't want to flush antifreeze out in spring, and are happy to spend the time going faucet by faucet.
Method 2: pump RV antifreeze through the system
Here you replace the water in the lines with RV antifreeze, the non-toxic kind made for plumbing (never automotive antifreeze). Camco sells two ways to get it in:
- RV Antifreeze Hand Pump Kit with Hose (36003): a manual pump with its own hose for pushing antifreeze into the RV plumbing. It needs no power.
- Permanent Pump Converter Winterizing Kit (36543): installs at the RV's own water pump so the pump can draw antifreeze in (straight from the jug, in most setups). Once it is fitted, winterizing next year is quicker.
Run each faucet, hot and cold, until antifreeze comes out, then flush the toilet until you see it in the bowl. With antifreeze in the system, the drain traps fill as you go.
Best for: owners without a compressor, RVs stored where it gets very cold, or anyone who wants the traps and low spots fully protected in one pass.
Either way: drain the water heater, and bypass it for antifreeze
An RV water heater holds several gallons. Drain it for either method, with the heater off and the water cool. If you pump antifreeze and the heater isn't bypassed, the tank fills with antifreeze you then have to throw away. A bypass isolates it:
- Quick-Turn Permanent Water Heater By-Pass Kit (35983): a quick-turn valve, installed permanently, so the water heater tank doesn't need to be filled with antifreeze.
- Supreme Permanent By-Pass Kit, 6 gal (35953): brass valves for non-restrictive flow, with an 8-inch hose for a 6 gallon tank. Camco says it saves gallons of antifreeze at every winterizing.
If your RV already has a bypass, our water heater bypass valve guide explains how to set it.
While the water heater is empty, it's a good time for basic maintenance. The Water Heater Tank Rinser (11691) lifts the sediment that collects at the bottom of the tank and washes it out. Suburban (Mor-Flo) water heaters take an anode rod: Camco's aluminum anode rod (11563) protects the tank by attracting corrosive elements in the water. Heaters that don't take an anode rod use a drain plug instead. The 1/2-inch NPT drain plugs (11630) come as a 2-pack, and Camco recommends 3–5 wraps of Teflon tape on the threads to prevent leaks.
Our take: which should you buy?
- You own a compressor: a blow-out plug, a bypass kit, and a jug of RV antifreeze for the traps.
- No compressor: the hand pump kit or the pump converter kit, plus a bypass kit.
- Belt and braces: blow out first, then pump antifreeze through. It uses less antifreeze than filling lines that are still full of water.
FAQ
Does blowing out the lines protect the drain traps?
No. Air clears the supply lines, but the P-traps under each drain still hold water. Pour RV antifreeze down every drain and into the toilet bowl.
Can I use any air compressor?
Camco's instructions specify an oil-less compressor, so no compressor oil gets into your drinking-water lines.
Do I need a bypass kit if I only blow out the lines?
Not strictly. Drain the water heater first, and air through the empty tank does no harm. The bypass matters when you pump antifreeze, because it keeps the tank from filling with it, so set it before you do.
Find every Camco winterizing part in the Camco collection. Everything ships from our warehouse in Upland, California.