Horizontal vs undermount propane tanks

[kennchen]

There seem to be two styles of horizontal propane tanks: regular horizontal, and horizontal undermount, which seems to cost at least twice as much for a similar capacity.

Horizontal: https://www.amazon.com/Manchester-1175TC-White-Horizontal-Tank/dp/B0006LA4FY
Undermount: https://www.amazon.com/Manchester-Tank-6813-Horizontal-Capacity/dp/B005GY9UHY

Is there any reason not to just get the horizontal tank and mount it underneath the vehicle? Are there any secret differences?

 

[highdesertranger]

is the horizontal DOT approved? I believe the horizontal is for use in forklifts and the such and most of them dispense liquid propane. the undermount is for RV's and it will be DOT approved. the undermount also dispenses propane vapor and that is what you want.

why mount the tank/cylinder?

DOT = Department Of Transportation

highdesertranger

 

[kennchen]

Looks like there are horizontal tanks that are DOT approved: https://www.amazon.com/Flame-King-YSN201HZL-Cylinder-Horizontal/dp/B07Y5PQXJ6

I don't have to mount the tank itself; in fact, I could build & mount underneath a container for the horizontal tank, so that it can be pulled out for easier refilling.

Are you sure that these horizontal tanks would dispense liquid? I have seen on RVs these kinds of horizontal tanks sitting in a small externally accessible cabinet.

 

[highdesertranger]

that one you linked to in post #3 dispenses vapor. you must make sure with the horizontal tanks as a lot of them are meant for fork lifts and dispense liquid propane. highdesertranger

 

[bonvanroulez]

I bought a trailer that had one of those horizontal tanks bolted on the hitch frame, it was the Manchester tank just like the one in your first link. It was a huge pain because it had to be unbolted to be refilled as it must be refilled vertically, and some filling station guys were put off because it was an oddball. I replaced it with a normal 20 lb bottle.

Other than that one I've only seen them in installations like a pickup bed camper where there might be vertical height limitations in the storage location.

If you're mounting it under the vehicle, recommend you use the ASME tank that's designed for permanent mounting like the one in your second link. It's designed to be under the vehicle and to be filled in place. As said, that other horizontal tank must be removed and filled in the vertical position. And the fill valve and gauge on the end will be more vulnerable to road debris.

 

[tx2sturgis]

...the undermount is for RV's and it will be DOT approved.  


DOT = Department Of Transportation

Correction:

DOT approved propane tanks are portable (carried by hand or small hand truck) and require re-certification every 10-12 years or whatever they change that to later on.

ASME tanks are not portable...they are designed to be frame mounted, and do not require periodic re certification.

Big difference.

 

[kennchen]

I bought a trailer that had one of those horizontal tanks bolted on the hitch frame, it was the Manchester tank just like the one in your first link. It was a huge pain because it had to be unbolted to be refilled as it must be refilled vertically, and some filling station guys were put off because it was an oddball. I replaced it with a normal 20 lb bottle.

Other than that one I've only seen them in installations like a pickup bed camper where there might be vertical height limitations in the storage location.

If you're mounting it under the vehicle, recommend you use the ASME tank that's designed for permanent mounting like the one in your second link. It's designed to be under the vehicle and to be filled in place. As said, that other horizontal tank must be removed and filled in the vertical position. And the fill valve and gauge on the end will be more vulnerable to road debris.

But if I put the propane tank in a box and mount the box to the underside, wouldn't that be cheaper, easier & still protect the tank?

 

[highdesertranger]

ah you are correct Texas.

Kennchen protect it from what?

highdesertranger

 

[kennchen]

Road debris, etc

 

[highdesertranger]

if you get the correct tank you don't need a box. you know you can get one from a junk yard cheaper than any of those you listed. highdesertranger

 

[Zythophile]

I've been doing a mess of research and weighing, for my needs/wants, all these different options as well. In my ideal build (yeah, we'll see, hah) I'd be going with either that exact undermount tank linked in the initial post (the second link) or something very similar, with a fill-port mounted on a bracket closer to the edge of the vehicle.

Two reasons: 1) Were there to be any leakage, it's all outside of the vehicle, so no need to build a sealed enclosure, or drill another hole in the bottom of the van for a vent; 2) That's just that much more internal cubic footage freed up for other uses.

The big disadvantage with going with this plan is filling; I expect there's far more places out there where you can fill or exchange your typical propane tank vs. places you can fill up via a hose. But it seems most folks can go a good while between fills when using these sized tanks, so that may not be much of an issue in the end.

There's a nice post on such an install here: https://www.vanlifeoutfitters.com/i...erneath-a-promaster-van-with-remote-fill-kit/

 

[highdesertranger]

Zythophile I checked that link. I hope he is not driving off pavement. if you plan on driving off pavement you need to pay extra attention to the mounting and running of hoses. highdesertranger

 

[tx2sturgis]

Just a heads up...normally with a frame-mount tank, if you are camped somewhere and that tank runs low or empty, and traveling to fill it would be inconvenient, then you can unscrew the POL coupler and then screw it into a portable 20lb tank sitting on the ground. This can be done with 'extend-a-stay' kits or you can DIY it.

 

[Zythophile]

Zythophile I checked that link.  I hope he is not driving off pavement.  if you plan on driving off pavement you need to pay extra attention to the mounting and running of hoses.  highdesertranger

I agree! I know if I ever get around to doing a project and I go this route, I'd be adding some additional protection to all that gear. Peace of mind and all that.

 

[Bear_from_OBX]

The frame mounted tanks designed for chassis mounting under an RV, bus or specialty vehicle generally have much thicker tank walls, better corrosion control coatings and different valve and fill port protection to better handle an impact during a vehicle accident, road debris impact, splashing & spraying water exposure, road salt spray from treated roads and mounts to better protect the tank and fittings from the attached vehicle flex and vibration. Most of the newer designs have an excessive flow cutoff valve built into the tank outlet that stops or minimizes the escaping gas flow if a valve or connection component is broken to minimize leaking gas in an accident as well. There is a major difference between the two tank designs and for good reason.

 

[DannyB1954]

Most propane tanks need to be re certified about every 5 years. Tanks made for RV's are usually certified by the Underwriters Laboratory and do not need to be tested. These tanks of course are more expensive.

 

[MotorVation]

I wish I had a large propane tank underneath the van but I'm not willing to fork out that kind of money for one. It would be great to fill up and not have to worry about it for months. That said, I have a 20lb tank and I use it for my Wave 3 heater and to refill 1 lb bottles for other uses. The Wave 3 sips propane on low (200 hrs on a 20lb tank) but I don't like to run the tank too low.

When I'm in Quartzite, Ehrenberg, etc, I like to go to Patty's RV Park in Quartzsite to get my propane. No attitudes because I'm not filling up an RV tank. In fact, they have two lines, one for RV's and the other for cars. 3.00 a gallon attitude-free. Love it. 455 E Main St.
I'm in no way affiliated with them. Just a happy customer.

 

[user 27148]

I'm in Santa Cruz, California, and just found a guy with a bunch of used ASME RV tanks. As mentioned already, ASME tanks are permanently mounted and don't need recertification. So, cleaning up the paint and remounting them makes for a wonderful addition to the van life.

It's good to understand what a person is doing when they install propane though; Understanding regulators, hardline and hose options, appliance regulators, additional options like shutoff valves and pressure gauges, and so on. It's also very important to understand the safety needed for proper venting, understanding CO2, having safety sensors, and so on.

Anyway, if anyone is interested in a used propane tank, let me know. We can figure out shipping and whatever other costs would be associated.

 

[Camper]

I'd like to have one if the price is fair.

 

[user 27148]

I'm going up there this Saturday. The tank that I'm picking up for myself is 12" in diameter and 34" long and weighs 71 lb empty. The rest are longer than 36", so let me know if that is within your size range (yours will be longer than 36", at least according to the guy on the phone). The guy I talked to seemed nice enough, but I'm a technician that rarely trusts others' measurements.

Anyway, figure on shipping 100lb from Santa Cruz, California for your shipping cost, or you can pick it up if you want to travel to me.

The last two photos are of what I'm picking up, the first two photos are of all of his tanks, which it looks like he has other shorter tanks. I'll see when I get there.

Now, if there are site guidelines or rules for doing business/trades like this here, get me up to speed with a link. I'm not trying to break rules, while also wanting to follow good form.