RV Plumbing Fittings

What size PEX fittings do most RV water lines use?

Most RV fresh water systems run on 1/2 inch PEX, with some coaches using 3/8 inch on branch lines to fixtures. Measure the outside diameter of your existing tubing and check whether your rig uses crimp, cinch clamp, or push-to-connect style connections before ordering. This collection carries elbows, tees, couplers, valves, and adapters in the common RV sizes so you can match what is already in the bay.

Are these fittings compatible with PEX, polybutylene, and standard RV tubing?

Yes. Our RV plumbing fittings cover PEX-A and PEX-B tubing, legacy polybutylene lines found in older coaches, and standard reinforced PVC water hose. Brass and acetal (plastic) bodies are both stocked so you can match the material your system already uses. If you are mid-repair and not sure which line you have, text or call 817-984-1852 with a photo and we will confirm the right fitting.

What else do I need for a full fresh water plumbing repair?

Plan on the fittings themselves, a short length of replacement tubing, the correct crimp rings or cinch clamps, and the right tool to set them. Many owners also pick up a winterizing kit and tank chemicals while the bay is open. See related parts in Thetford tank chemicals and replacement Ventline vent accessories if you are tackling a larger maintenance round.

Do these fittings work for winterizing an RV?

Yes. Bypass valves, blowout plugs, and inline tees in this collection are the same parts used to isolate the water heater and pull antifreeze through the system each fall. If you are also servicing the tank itself, pair the fittings with a draining schedule and check our 10 gallon RV water heater collection for replacement units and anode rods.

How fast do RV plumbing fittings ship?

In-stock fittings typically ship within 1-2 business days from our Texas warehouse. Orders over $100 ship free within the contiguous US. If you need a part overnight to finish a job, call 817-984-1852 and we will confirm stock and the fastest carrier option before you check out.