What are the Common Types of Propane Fittings Used on RVs?

If there's one thing that's simple and straightforward on RVs, it's propane fittings—said no one ever.

It's no wonder propane fittings can be so confusing. There are half a dozen different types, and they all do different things. Some connect to your regulator, some connect directly to your tank, and some are found on hoses, T-fittings, and adapters. Because of this, it can be difficult to tell what fittings you have or what you need to do the job at hand, whether that's replacing a part, connecting a gas grill, adding an extension hose, or modifying your system in some other way.

In fact, we get so many questions on propane fittings, we created this guide to clear up the confusion, help you identify what fittings you're looking at, and help you understand what they do. We're not sure who decided propane fittings were supposed to be complicated, but we respectfully disagree—we'll break it all down for you below so you can become a propane fitting guru. Or you know, at least hook up your grill or use your water heater, because that's what you're really here for.

Let's do this!

You can also have our expert Jake walk you through the different types of propane fittings in this helpful video.

Types OF RV Propane Fittings

We'll start by laying it all out there; there are 7 main categories of RV fittings. (If none of them ring a bell for you, don't worry. We'll explain.)

POL Fittings
Type 1 (ACME) Fittings
Inverted Flare Fittings
NPT Fittings
Flare Fittings
Quick-Disconnect Fittings
1"-20 (Disposable Cylinder Port) Fittings

RV propane fittings have both male and female ends, and sometimes the fittings come in more than one size. So yes, there are a lot of potential combinations.

The three main criteria to look at when identifying a fitting are these:

1. Where is the fitting located? For instance, is it connected to a regulator or a tank? Is it located on a supply hose or a portable accessory? Although there is some overlap, propane setups generally use different fitting types for different purposes. The fitting's location on your setup is going to give you the biggest clue as to what it is.

2. Is the fitting male or female? This is usually easy to determine just by looking at the fitting. Again, propane setups generally use different types for different purposes.

3. What size is the fitting? Some fittings are universal (for instance, there's only one size of POL fitting). However, other fittings like NPTs and flares come in different diameters. Some of these will be more common than others and will be used in different locations. We've included a chart with the exact thread diameters in case it comes down to measuring your fitting.

Armed with this knowledge, you'll be able to identify pretty much any fitting you come across.

Thread Diameters for NPT, Flare, and Inverted Flare Fittings

So...What Type of Fitting Do I Have?

Let's take a look at the most common RV propane fittings, what they look like, and where they're usually located. Nine times out of ten, this is all you need to identify what type of fitting you have and what you need.

The biggest clue when identifying a fitting is going to be its location. Where is the fitting you're trying to identify?

On the Tank
On the Hose Going Into the Regulator
On the Hose Coming Out of the Regulator
On the Supply Hose (Connected to Main Propane Line)
On a Tee Fitting, Grill, Outdoor Kitchen, or Accessory Port
On a Portable Propane Cylinder

On the tank:

If the fitting is located on your actual tank, it's most likely a POL or Type 1 fitting. The female fittings are on the tank itself, and the male fittings connect to them.

You'll be able to easily tell whether you have a POL or Type 1 fitting just by looking at it. Type 1 fittings have a distinguishable colored connector that allows you to hand-tighten them. Type 1 fittings also run on the outside of the tank valve, while POL threads run on the inside.

You're most likely to find POL fittings on non-removable motorhome propane tanks. These fittings will connect the tank itself to the regulator. On the other hand, you'll likely find Type 1 fittings on removable propane tanks on fifth wheels and travel trailers. These fittings will connect the tank to the pigtail hose (which then feeds into the regulator).

If you'd like to connect a tee fitting to your setup, you can typically do it here by adding the tee between your tank and regulator. You'll need a tee with the appropriate fitting (either POL or type 1) to connect to the tank side.

Hose Going Into Regulator

Looking at your pigtail hose where it attaches to your regulator? You're most likely looking at a 1/4" NPT fitting or inverted flare fitting. (The female end is located on the regulator, ad the male end is on the hose.) NPT fittings are found on most regulators, whether they're single or dual stage. The exceptions are auto-changeover regulators, which automatically switch your fuel source from one propane tank to another when the first runs out. These regulators have female inverted flare fittings (called FIF fittings), and they attach to male inverted flare (MIF) hoses.

Not sure what type of regulator you have? Here's a quick reference point: if your regulator has a gold adapter fitting, it has a FIF fitting and requires a MIF hose. If it does not have a gold adapter, it has a 1/4" female NPT fitting and requires a 1/4" male NPT hose.

You can also tell the difference between male NPT and inverted flare fittings by looking at their thread size. The circumference of MIF threads becomes narrower, while the circumference of NPT threads does not (see image below).

NOTE: You might see male and female NPT fittings referred to as "MPT" and "FPT" fittings, respectively. These are interchangeable with "NPT," so don't be alarmed if you see these abbreviations at times.

Male NPT Fitting vs Male Inverted Flare Fitting

Standard Regulator vs Auto Changeover Regulator

Male NPT fitting on pigtail hose attached to female NPT fitting on regulator

Hose Coming Out of Regulator

The hose coming out of your regulator and bringing propane to your appliances will usually have a 3/8" NPT fitting. The female end is located on the regulator, and the male end is located on the supply hose.

Male NPT hose into female NPT regulator connection on propane tank

Supply Hose Connected to Main Propane Line

The fitting that attaches your supply hose to your RV's main propane line will typically be a 1/2" or 3/8" flare fitting. (NOTE: these are different than inverted flare fittings and belong to their own category.) The female ends are usually found on the supply-hose end, while the male fittings are usually found on the main line itself.

Male and female flare fittings connecting a propane supply hose to main propane line on RV

Tee Fitting, Grill, Outdoor Kitchen, or Accessory Port

Do you have a weird fitting sticking off your RV or accessory and you're not sure what it is? It might be a Quick-Disconnect, or QD fitting.

You can often find these fittings anywhere you might temporarily hook up an accessory and later remove it, and that's because QD fittings are extremely easy to connect and disconnect. They're often found in outdoor kitchens so you can connect propane grills or fire pits. They're also often found on tees.

Quick-Disconnect Fitting Diagram - Hose Connected to Grill

Quick-Disconnect Fitting Diagram - Hose Connected to Tee

Portable Propane Cylinder

Do you use throwaway propane cylinders for your grill or other propane accessory? Or maybe you want a disposable tank as backup if you run out of fuel? Your disposable cylinder most likely came with a male 1"-20 fitting (also called a disposable cylinder port). This 1"-20 fitting attaches to a hose with a 1"-20 female connector.

So, to recap, the best way to identify what propane fitting you have or need is to look at its location. Determine if it's a male or female fitting and what size it is, if more than one size is available. From there, you should be able to connect a gas grill, hook up an external propane tank, or hook up whatever propane setup you can imagine.

And if you're still not sure and have a question about your specific setup, go ahead and leave your question in the comment section below! We're happy to help take the "pain" out of "propane" any way we can.

About Amber S.

As a content writer for etrailer, I might spend my morning loading and unloading a bike on five different bike racks to figure out which is easiest to use. I might be in the parking lot, taking pictures of an impressive RV battery setup our techs came across in the shop and discussing the benefits of the setup with the owner. I might spend an afternoon in a manufacturer training class for some hands-on experience with new products, and then sit down to assemble all this information into a coherent article.

At etrailer, one of our core values is that we are always learning, and I learn something new every day. I start each morning with the goal in mind of taking all of this information and figuring out the best way to answer the questions people ask us (and the ones they don’t know to ask yet), and helping people get the solutions they need to make their lives easier, safer, and more fun. I’m a DIYer at heart, so it brings me great joy to help a fellow DIYer find what they’re looking for, whether that’s a product, an answer, or a community.

2 Steps for Hooking Up an External Propane Tank to Your RV

RV Propane 101: How Does My RV's Propane System Work?

How (And Where) to Connect an RV Propane Grill

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Written by: Amber S.

Updated on: 3/18/2022

Berta

1/26/2023

The original supply line (one that connects to the rv) is way bigger than 1/2 in or 3/8. I got a 1/2 inch female flare to connect hose to main rv supply and it is at least a size to small! I can't find information ANYWHERE on propane connections larger that 1/2 inch. Did they make connections larger than that early on? It's a trailer from the 1980s

Mike L.

1/26/2023

You might have something a previous owner rigged up, as I'm not familiar with fittings that large. We don't offer anything in that size, but your local big box store or plumbing house should offer parts that would work. I would also say that unless you're experienced in this type of work, you might want to have a shop handle this, as leaks in a propane system could prove to be dangerous if not disasterous....

Weston Z.

12/24/2022

Very helpful article. Thank you.

Mike L.

12/26/2022

You're very welcome, I'm glad we could help!

Tim

11/15/2022

Inside the tank valve (20 or 30#) there is a rubber seal. Do you have source to purchase these seals?

David B.

11/15/2022

Are you talking about the actual valve on the tank or a fitting you attach to the tank?

Tim

11/21/2022

@DavidB Yes, inside the valve.

David B.

11/21/2022

Sorry Tim but no we don't have parts to repair valves or anything like that. We have fittings tees regulators and all that jazz but nothing to replace the inner workings or seals. Just parts that attach to the tank.

Helpful Links

propane-parts

Jim T.

6/22/2022

Trying to add a tee fitting (for a quick disconnect) on my motorhome propane tank regulator (permanent mount tank) It has a 1/2 " male flare fitting coming out of the regulator with a 1/2" female flare hose attached; that's where I want to split it. So the tee fitting would need to be 1/2" male to 1/2" female with a 1/2"pipe thread on the other leg (1/2in leg size not critical )

David B.

6/22/2022

Sorry Jim, we do not have any T-fittings that size at this time, you will need to find the fittings you need at a local hardware store or someplace that sells propane and propane accessories.

John H.

10/5/2022

@JimT What brand regulator do you have? I haven't seen a regulator with 1/2 inch threads before.

Jim

6/2/2022

WHO MAKES UP THESE HOSES FOR PROPANE, CAN'T FIND ANYONE HERE IN GREENWOOD. TOOK FITTING OFF MY MAIN LINE,IT WAS VERY WET AND FULL OF BLACK JUNK! WHAT IS THAT FROM!TRAILER IS A 2014 TRAIL RUNNER. IS THERE ANY KIND OF FILTER TO CATCH THIS STUFF?

David B.

6/3/2022

The black tar material comes from the rubber hose. You can clean it out with soapy water and let air dry. Or get a new hose(I will link you to our selection.) Filters are a grey area, they work for some, don't for others. You can find one at most hardware stores.

Helpful Links

s.aspx?qry=propane+hose

Gary

4/27/2022

Hello. Are all Type 1 propane connectors required to have the auto shut off feature when there is a leak on the low-pressure side of the regulator? Are there Type 1 propane connectors available that provide this auto shut off safety feature better than other products? Thank you.

David B.

4/27/2022

Type 1 fittings do not have auto shut off features at all, there is not any regulation for that. You would need the GasStop # GS24FR . Just pair it with the GasGear 90-Degree Propane Hose - Type 1 x 1/4" Male Inverted Flare - 12" Long - Stainless # GS97FR . This will give you the peace of mind you are looking for. If you have any other questions come back and ask, I'll be here to help.

David B.

4/27/2022

Gary

4/28/2022

@DavidB Hello, Your description of Camco Type 1 connections includes "Provides thermal protection in case of fire and excess flow protection in case of broken gas line." Do all of these products have this feature? How would they or the GasStop product know the difference from all gas appliances running and a propane line leak? Thanks.

See All (8) Replies to Gary ∨

Rick M.

4/26/2022

Hello! Question please, on my camper, the propane line from my regulator to the connection on my camper is 3/8 male/female ends and a hose diameter of 3/8. I have a hose diameter of 5/16 with 3/8 ends. Will this smaller size diameter hose work with my camper propane usage? Thanks for any help…

David B.

4/26/2022

Will it work? Maybe. I would need to know the brand/item number to be able to tell you 100% yes or no. You will be running low pressure from the regulator so I'm not really worried about that. I'd just make sure it can let enough propane flow to meet the BTU requirements of your applications and regulator. If you need anything else I'll be here to help.

Helpful Links

article-categories.aspx?productgroup=propane

John

4/17/2022

Best article on the internet for this topic. Thank you! Saved me many hours.

David B.

4/17/2022

Outstanding! Thanks for the feedback.

John H.

10/5/2022

@John What sort of propane issues were you having?

Ron P.

3/19/2022

I am trying to put in a quick connect right after the regulator on my 2017 motorhome using a t fitting coming out of the regulator to the hose for the rest of the motorhome. Is there one already built to do this. I can install just need the part number can’t find one on line.

Les D.

3/21/2022

@RonP is the outlet side of your regulator a female 3/8 inch fitting?

Ron P.

3/21/2022

@LesD yes it is out of regulator and a 1/2” flare to the hose

Ron P.

3/22/2022

@LesD yes it is .

See All (7) Replies to Ron P. ∨

Gil

2/8/2022

How do I use the low pressure propane quick connect on my motorhome to refill 1lb disposable canisters? or can I? I see plenty of adapters for QCC1 / Type1 Propane Tank to 1LB Throwaway Disposable Propane Bottles but cannot find any information on using the low pressure quick connect to refill the small disposable canisters. Is it even possible? I like the mobility of using the small tanks for my small bbq so I really dont want to modify it to be connect to the motorhome with a hose. I just want to be able to refill the disposable bottles. Any thoughts on what I need to get to accomplish this? thanks

Les D.

2/8/2022

@Gil I applaud the IDEA of refilling 1-pound propane tanks, as they are non recyclable and take a toll on our environment. I know that some people attach a 20 pound tank to a one pound tank, but the method is unsafe. Also the sealing 0-rings on one pound tanks are only made for a few uses, and then are prone to leaking. I would recommend using a hose when ever possible. If you let me know your propane setup and needs I can make some specific recommendations.

Gil

2/8/2022

@LesD The motor home has a quick connect on the side, the BBQ I have is just a small weber "go anywhere" bbq designed for the 1 lb disposable canisters. I like the idea and portability of the canisters. But I guess if there is a easy way to attach a hose from the motor home to the regulator on the bbq I could use that sometimes when convenient. But would like to also be able to use the cannisters when needed. As in taking the bbq to the beach or something like that. Sounds like the recharging the 1 lb cnisters is not really the best idea, thanks for any input. Gil

Les D.

2/9/2022

@Gil propane appliances like cook tops, ovens, heaters, and such, can only have the propane source pass through one regulator. On an RV there is a regulator right after the propane tank that steps down the pressure to a usable level for the appliances to use. In the case of your Weber Go-Anywhere Gas Grill, it has a regulator right where the propane connects to the grill. If your quick-connect source is after the RV regulator, and it likely is, then your propane will be double regulated and the grill will not work properly. Trace the propane line from the quick-connect to the propane tank and determine if it is sourced before or after the RV regulator. If your quick connector is before the RV regulator then you can just hook it up to the grill. Since your grill was intended for disposable bottles you will need the MB Sturgis # 100476-120-MBS small appliance hose. f your quick connect is AFTER your RV's regulator, then it will pass through two regulators and your grill will not operate correctly. You will need to remove the regulator from the grill. However, that makes is useless to disposable bottles. In this case, You could put a tee after the RV propane tank, and before the regulator, and connect a quick connect hose. I have linked some articles that describe each of these options. I too had this same issue two years ago and in light of the effort required to change the grill settings I decided that the grill would be a dedicated camping grill only. I took the regulator off the grill and got a long hose to connect is to the camper.

David T.

1/21/2022

After I sent previous comment I realized I had not mentioned something I need verification on. When I was in Columbus that winter I mentioned and had the bulk tank installed, I was present when it got done. However I don’t remember if the propane coming from bulk tank went through a regulator or not before it entered my regulator via a copper line. I read one of your answers regarding not using 2 regulators would you please advise me on this. I found you while trying to educate myself on the national propane association guidelines/specs pages. Note: 3 other company employees were in same camp ground with me and all new to RV life. They all praised me for talking them into having installed on the rigs because of the incredible cold which started just 2 weeks after our arrival. Sincerely, just a long winded 67 y.o. retiree trying to enjoy life. David

Les D.

1/21/2022

@DavidT thanks for relating your adventures to our readers. As with most DIY projects, it pays to have a knowledgeable person to help you, and this is especially true of handling propane. If you don't feel confident, get an experienced installer. To address regulators, you are correct, you do not run propane through two regulators, as most appliances will not work under that circumstance. You can simply look at your bulk tank and follow the service line to where it goes. Most likely it attaches to a fitting between your existing tank and the regulator.

David T.

1/21/2022

Hello folks, I am so impressed with your website that I just had to say hello and tell you how much I wish I could have found info like you produce back when I started living full time RV. You get 5 stars from me. Had many adventures trying to adapt propane hoses so as to use larger tanks.I traveled for a living for 20 years, I now own my 3 rd RV ( 40 ft 5th wheel ) and retired 2 yrs ago. It is in my back yard serving as guest quarters situated so I can take it out and put it back. Recently put in new 50 amp service, water and sewer. Have been using 2 -100 lb propane tanks to supply it. Had a back injury 1 1/2 yrs ago so, loading those into a GMC 3500 Denali Dually has become Very difficult. Now working on putting in a 150-250 gallon tank requiring installation of copper line to my onboard regulator. (Note: I had a bulk tank connected to my 30 ft when in Columbus several yrs ago. We had temps of 30 below with wind chill of 40 below that winter so good thing I knew it was critical to have it done). Propane company didn’t give me any hassle. WOW, the many regulations I have encountered, with this here in north La., 1) getting a company to supply my needs, 2) their policy regarding distant from “things”, 3) they will not rent me a tank, 4) or install line to RV. However I had planned all this to the best of my ability ( raised on farm using propane and retired electrician) I am making progress and will “getter done” when I find a tank to buy ( they say tanks are in short supply nationally. Keep up the good work of this publication, RV owners/ readers need your kind of knowledge and help. Lot of topics covered and questions you answered I had to learn the hard way. Wish me luck. Thank you and sincerely yours, David

Mark

1/14/2022

By my experience most of the 2 tank regulators have a check valve where the tank lines connect. Some have a check ball and spring behind the 1/4" male npt to 1/4" female inverted flare adapter. On others the check valve is built into the 1/4' npt to 1/4" inverted flare adapter. My regulator is good but the check valve is bad. Do you have or can you refer me to a source for the built in check valve / adapter? Thanks, Mark

Les D.

1/17/2022

@Mark we do not have propane regulator repair parts - only complete regulators. I am aware that some regulators have a check valve. Some also have an Excess Flow Valve that closes if a broken line is detected by excess flow. This EFV can be reset by shutting off gas and letting it rest for 15 minutes, then opening the valves very slowly afterwards. I have posted a link to all of our regulators below.

Helpful Links

dept-pg-propane-sf-regulators.aspx+

Hi C.

12/22/2021

Hi i just purchased a stove, guy said it was connected to propane. But the hose coming out of the stove is a small yellow one i believe both ends are 3/8, so what kind of connection do i need to be able to hook it up to a propane tank from the stove which is a 3/8 connection yet the tank is type1. And do i need a regulator? Thanks

Les D.

12/22/2021

@JRogerLBC I would like to help you, but I need a bit more information. Is this a oven and cooktop in a trailer, or is this a free standing outdoor cook accessory? Can you send me the brand and model number? The "small yellow hose." Could that be a copper gas line with flared 3/8 in ends, or is it rubber?

Hi C.

12/22/2021

@LesD Ok. Its a kenmore. Has four burners an oven. Yes its 3/8 at both ends of the yellow hose. Bout three ft long. Will b used in door inside a chirch kitchen. Will be used only twice a week.

Les D.

12/22/2021

It sounds like you need a Camco # CAM57703 propane pigtail with regulator. It has a Type-1 connector on one end like you would find on a 20 pound BBQ tank, and the other end has a 3/8 inch flared female connector. If your stove has a built in regulator you cannot use another one like is on this pigtail. If you are not absolutely certain about what you are doing you should call in a propane service expert to help you make your connections and check your vents.

Dennis E.

12/19/2021

What is the size of nut on a PLO fitting, Wrench size needed?

Les D.

12/20/2021

@DennisE, POL takes a 7/8 inch wrench

Wes

12/16/2021

I am looking for a fitting that will allow me to screw on a Type 1 hose (which is meant to screw onto a 20 pound tank fitting) onto a regulator. So either a regulator with a Type 1 outlet, or a flare-nut to Type 1 adapter. Do you know of such a thing?

Les D.

12/17/2021

@Wes, I have not seen a regulator with a Type-1 Female outlet. I think if you can tell me what you want to accomplish, I can come up with a solution. For instance, do you want to use the 20 pound cylinder on your travel trailer to operate a gas grill near the trailer that needs a regulator?

Wes

12/17/2021

@LesD I want to use a 20-pound tank to power a variety of accessories that usually take a 1-pound tank. Some of these don't have regulators. So I'd like to have the regulator at the tank, and then use a conversion hose to reach the appliances.

Les D.

12/17/2021

What about the Camco # CAM57703 . This connects a regulator directly to the 20 pound tank and has a 6 foot hose one the output side of the regulator. We also have this with a 12 foot hose # CAM57721 Keep in mind, for the items that have a regulator already, you cannot have two regulators in line.

See All (5) Replies to Wes ∨

Jennifer M.

12/8/2021

Hello! I have a 1995 motorhome that I’m trying to put an extend a stay on. The one I ordered is a 1/4 in fitting but it’s apparently way too big for what’s on my motorhome. What would be the size on my motorhome if the quarter inch is way too big? Thank you for your help!

Les D.

12/9/2021

@JenniferM it sounds like you are installing a Camco # CAM591234-Port Tee with hoses. I attached a link to the product video that shows all the parts and fittings and how they are to connect. There are no fittings smaller than one quarter inch. so it is unclear what you need to do. perhaps you can send a picture of your setup?

Helpful Links

cam59123

Jennifer M.

12/10/2021

@LesD Hi Les! Thanks for taking the time to help me! I think I have POL size since the “extendA stay” fittings are far larger than my current motorhomes fittings. I’d send a picture but not sure how.

Les D.

12/13/2021

@JenniferM I have sent an email address for you to send pictures to.

See All (5) Replies to Jennifer M. ∨

James

11/18/2021

I would like to convert the tank fitting to type1 for my propane converted generator. I notice they have different BTU ratings. I have a Predator 3500 watt generator. I saw a 200,000 btu connector. Would this be suitable for me? Thank You Jim

Les D.

11/24/2021

It sounds like you are getting a pigtail where one end fits in your propane electric generator and the Type-1 end connects to your propane tank. 200,000 BTU throughput would be enough for this use. You may need a regulator unless one is built into the generator.

James

11/24/2021

Hi I purchased the dark green type1 connector. I received it yesterday. I had a Pol connector that came with the propane conversion kit. There is a regular that it's connected to. The new dark green connector. IT WORKS GREAT!

Les D.

11/26/2021

@James Glad it worked out so good.

Norman K.

11/3/2021

Clear and understadable. Well-written and informative. I will print and laminate. BTW, is there a way to fill my onboard RV tank? RV is stationary and propane company will not come and fill it. Lastly, if I opt for the company's pig and locate it next to the RV, how can I also run a 100' line to my travel trailer (has the two twenty pound tank setup.) Thanks

Les D.

11/4/2021

Mobile propane trucks will generally not fill 20-pound tanks. I have two 20-pound tanks on my travel trailer, and the local refill station makes me take them off the trailer before filling them. You won't find 100 foot rubber propane hoses because you are not suppose to use them full time. For that length run you will need the gas company to run an underground hard-line for you. You could get a 100 pound tank so you don't have to refill as often, but it is cumbersome to take to the refill station.

Norman K.

11/6/2021

@LesD Thanks got the 100# and I ran gas pipe at my home so we'll see.

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