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Can you use flexible hosing to connect CO2 tank to regulator?

10K views 25 replies 11 participants last post by  dipan 
#1 ·
Does anyone run a flexible hose from their CO2 tank to the regulator? I was thinking it would allow you to permanently mount the regulator and manifold to a wall or the inside of the cabinet. This way when you disconnect the tank, your regulator and manifold remain secure, not flopping around and risking damage. It would also give more flexibility in where to place the manifold, regulator, and CO2 tank. If you've done this, pictures would be great, as would parts info for the hose.
 
#2 ·
You can and I saw others use this method.

CO2 tank to CGA-320 to female 1/4" NPT adaptor to 1/4" NPT male to 3/8" hose adapter to CO2 line then go in reverse to connect the hose to the regulator would be one way to do it.

You can also get a mounting bracket to attach the regulator to a wall stud or such.
 
#3 ·
It can be done, but you would have to consider a few things. The hose would have to me made as it would be holding 800 pounds of pressure so it will be heavy duty.


When you remove regulator you would have to bleed off that pressure and the longer the hose the more CO2 would be wasted. Might need to build the hose with a tee and a valve so you could safely bleed of the hose pressure.


I did not remote mount my regulator, but I did remote mount my needle valve, solenoid, and drop checker. I used CO2 grade hose and as it is after the regulator the pressure is down to about 45 PSI.











LionelC
 
#4 ·
The only issue would be the tubing and connectors need to hold 800 psi of pressure. Most plastic tubing won't do that. If its mounted to the wall you could do 1/4" stainless tubing to swaglock maybe, but I don't know what the max operating pressure for swaglock connectors are, but its probably fine (famous last words...)

You can also put a valve on the output of the regulator so you don't lose the pressure/gas on the line when you swap out tanks, that way you don't need a bleed off which loses you gas.
 
#5 · (Edited)
Regarding the 800psi, I was assuming that there are high pressure gas line hoses similar to what you have for hydraulics. They handle pressure in the 1000s of psi.

Regarding CO2 loss, if we are only talking at most a few feet of hose, I would think it would not be an issue unless you are prone to disconnecting and reconnecting the hose for some reason (ie new setup and you just can settle on where things should go). Hopefully for the most part you are only disconnecting and reconnecting when refilling, in which case the loss minimal.

The other option here would be to just run a hose from the regulator to the manifold, but that doesn't have nearly the appeal.

@LionelC, I've also having been thinking a bit about the value of just having the needle valve remote, especially if you have multiple valves, and even more so if you wanted a separate solenoid for each valve. Thanks for sharing the details.
 
#6 ·
I mount my reg to the tank but do the rest on tubing once the pressure is cut down. The pressures mentioned may not be high enough as a full tank of CO2 can be quite a lot higher on a warm day and it is never really good practice to run any line near the rated pressure. For concerns about the loss of gas, I would not bother as the gas itself is so cheap. The amount in the line is likely to be far less than what you blow off when clearing the valve before mounting the reg. People often don't do this but when you look at having a bug or some debris in the valve and not clearing it, the result can be real awkward. CO2 is often hauled on trucks without covers on the tanks and that can let stuff (like bugs?) wind up in the valve. When you add the reg, this can let the bug go in to stop up some little passage. From there the story gets bad! Just good practice to do a quick open/close to blow stuff out first.
 
#8 ·
When I was talking about wasted gas I was assuming you would have 8 or 10 feet of high pressure hose. A couple feet should not be an issue. I am sure you can get some SS braided high peruse hose with NPT ends and remove the bottle connection from the regulator and connect it to one end of the hose and the other end to the regulator.
You could have it mage at Swagelock, or another reputable maker, but make sure they understand that it is CO2 going through the hose. The internals of a braded hose may be rubber or PTFE, but it needs to be rated for CO2 as it degrades certain plastics or rubbers.


I would suggest, as someone above did, just using some 1/4" SS tubing and Swagelock fittings. It would be flexible enough to remove the bottle and very reliable for long term use.


LionelC
 
#9 · (Edited)
The CO2 tank is mostly filled liquid CO2, whereas the hose will have gaseous CO2 (albeit at 800psi). I know at room temperature and 1 atm of pressure that gaseous CO2 takes up more than 500x the volume of liquid CO2, so if those were the conditions in the hose (which they are not), loss of CO2 would not be an issue. What I can't find out is the density of gaseous CO2 at 800psi. Given that, the length of hose, and the inside diameter of the hose, you could convert the gaseous CO2 loss into either lbs of CO2 or liquid volume of CO2.
 
#11 ·
I still haven't found the answer to my density at 800 psi question, but I did do a worse case calculation. Assuming 8' of 3/8" hose, and assuming there is liquid CO2 in the hose (not expanded gas, which is actually the case), the loss would be about .388 lbs of CO2. With 1/4" hose, it would be less than half that.
 
#10 ·
I'm not sure what the driving force is on wanting to move the reg off the tank that would make it worthwhile to me to do much extra. I find I do like to mount the solenoid, needle valve and bubble counter off the tank. I like doing this as it lets me put those where I can reach and see them easy as well as moving the "delicate " parts out of harms way. The reg body itself mounted on the tank is a pretty tough piece that I don't mind having there. With tubing going from the low pressure side of the reg to the other parts, I find it okay to just disconnect it and lay it back when I change tanks. This puts the question of high pressure tubing and fittings out as well as cutting the expense. I use somewhat low pressure as I feed reactors so just simple airline works for me. Somebody using higher pressure diffusers would have a different need.
This is a picture of one of my first setups where I still had the solenoid mounted with the reg but the rest remote. I'm still using this setup but now I do it slightly different on new setups.
You can spot that I have all my CO2 underneath the tank and turn and arrange things so that they are easy for me rather than using what might be called "standard" arrangements. I find I need to reach the needle valve far more often than the pressure reg and I want to see the bubble counter and be able to read the gauges so they get funny positions that work better for me.

No doubt that we all have different needs and preferences so this is certainly not the only way to go. Just an example that I find works for me.
 
#12 ·
It doesn't come in 8 foot lengths, but the Swagelok tubing I linked has an ID of .28in. At 8 feet, that's a total of 5.91in3.

A hose with a 3/8" ID would have a volume of 10.6in3, or .0459 gallons. If it is filled with liquid CO2, which, as you said, it will never be, so I don't know why either of us is doing this math, except I'm hooked now, and it's your fault, but anyway, I agree with your hypothetical math. It would be around half that for the tubing I linked.

I found one resource that says that half a pound of liquid CO2 will get you about 4.98 cubic feet at 80degF. If that's true (no promises), .28" ID hose, if filled with room temperature CO2, will waste a whopping .0055 ounces of liquid CO2, and your 3/8" will account for a bit over .01 ounces (you can do the math if you like).

Another resource says 1lb liquid will get you 8.62scf at 60degF. With the 20 degree difference, that's not far off from the 5scf per 1/2lb.
 
#13 · (Edited by Moderator)
Yes, all my fault. :smile2:

10.6in3 / .0459 gallons is exactly what I calculated. The problem with your "4.98 cubic feet at 80degF" math is that the assumption is 1 atm of pressure, which is a bit less than 15psi, but the gas is pressurized at 800psi, so will take up much less volume. I haven't figure out what the volume is yet.

Found a website for calculating the weight at 800psi:

Online - Calculation - Carbon dioxide

I used 853psi and 70F. I chose 853psi because I found the calculator called the state the CO2 would be in as the "boiling curve", and gave both fluid and liquid densities for it. I assume this is the state your CO2 in the tank and hose is always in as long as there is still some liquid CO2 in the tank. The tank cannot go above 853psi at 70F without first completely filling it with liquid (no gas).

At 853psi and 70F, the fluid density is 3.74x the gaseous density. So going back to my original calculation of a 3/8" diameter hose at 8' of length having .388 lbs of liquid CO2, it would have 0.104 lbs of gaseous CO2. So if you have a 10lb full tank, you would have to connect and disconnect the hose about 100 times before the tank would be empty. Now with a more reasonable .28" diameter and 3' length, it would be more like 500 times.
 
#16 ·
I used stainless steel braided lines like what would be used in a car's fuel system to go from my regulator to my manifold. Dont have a great photo showing it well, but its visible coming off the manifold at the bottom of the photo below. I'm sure something like this could be used to go from a tank to an externally mounted regulator as well if you can source the correct fittings. A good auto parts place (likely an old mom n pop and not one of the chains; or better yet a race shop if you've got any nearby) should be able to help fab something up if they dont have it available off the shelf.
 
#17 ·
Hoses are much harder to make so they don't leak at all with high pressure gas in them then they are for liquids. It takes a very tiny leak to dissipate all of the CO2 in the bottle over a few days. For that reason alone I would never try to connect the regulator to the bottle with a hose of any kind.

Years ago I worked a lot with 2000 psi air and regulators. We always, and I mean always, used stainless steel tubing to connect remotely mounted regulators to the air bottles, just for safety reasons. High pressure gas is very dangerous compared to high pressure liquids. This is the primary reason for not using any flexible hose or piping with high pressure CO2.
 
#18 ·
Apologies for the thread resurrection, but this is exactly what I was considering doing, remote mounting regulator and distribution manifold for 3 aquariums with 3 needle valves and solenoids, or just mounting the distribution manifold (low pressure hose connection) and leaving the regulator on the tank. Bettatail on this forum brought up this possibility for a new regulator build I asked for.

Anyone have any pictures of a remote setup, reg+manifold or just manifold? For some reason I am having a hard time picturing it, but it would be nice to have all the delicate bits like the metering valves and solenoids, fixed in the stand and not subject to injury during tank changes. It might also allow for use of a larger tank as there might not be as much clearance needed for bubble counters and tubes going straight up.
 
#20 ·
Apologies for the thread resurrection, but this is exactly what I was considering doing, remote mounting regulator
WORD of caution.. again.. Hardware store brass fittings, braided water hoses are NOT approved for 600-1000psi pressure..
You can easily "remote" your reg but it is not as easy nor cheap to do as one thinks ..


https://www.grainger.com/category/p...gs?attrs=Max.+Pressure|3000+psi&filters=attrs
https://www.interpumpfluidsolutions.com/wp-content/uploads/2019/07/PTFE-Hoses-EN.pdf
https://www.hydraulicspneumatics.co...uplings/article/21885071/its-a-material-world


Just pick the right fittings for the pressure.don't guess..


Anything past the regulator is a piece of cake pressure wise..
https://www.kegworks.com/2-to-9-way...gIVkIbACh27egTJEAQYASABEgIeAPD_BwE#item-16374


Of course you have choices.. 1 solenoid before the "manifold" or separate solenoids for each outlet.
You would need a metering valve for each though in all likelihood. If only to balance the outputs.
Yea gets complicated a bit.
Pic of 4 outlets, 4 valves, one solenoid..
You can do the same thing w/ plain pipe pieces..

https://greenleafaquariums.com/products/gla-pro-ds-4-aquarium-co2-regulator-dual-stage-modular.html


$15 and you have 5 1/4npt outlets. May need to modify the inlet (well remove the 3/8" part..)
https://www.northerntool.com/shop/t...MIwNmw0s2P6gIVD77ACh0XSgIhEAQYAiABEgIFRvD_BwE

Again all is put past the reg outlet..low pressure side
 
#19 ·
I no longer have pictures of my setups for using the reg on the tank and the rest remote but it is actually pretty simple if we get past the idea that a manifold is something complex. We call it a manifold but it is more a set of tee, y's, etc that let us split the flow.
So it gets down to add the reg on the tank, fittings and line of choice to the first place you want CO2, add a tee there and a needle valve at the end of that line and continue on to the next tank, adding tee and needle valve at each point of use until you get to the last stop. Being in your area, you likely know irrigation, so think of the irrigation system as one giant manifold!
One point to consider is the way pressure will work in the system. As we open one needle valve, more gas pressure goes out there and that means less flow at the other tanks. Your house plumbing is a large manifold situation and you know what happens when somebody flushes the stool while you shower?
So it can make it a little more tricky to get each tank set and keep it set as we change other tanks flow.
 
#21 · (Edited)
here is the picture of the possible setup from the web, but I do have several of such regulators with the support station manifold, actually my personal Co2 work station is such setup with two protocol station manifolds.
for such setup with protocol station(actually a supported manifold), it can be mounted on wall, in the cabinet or fish tank stand, connect to co2 tank with high pressure rating stainless steel hose(normally 3500 - 5000 psi pressure rating).
the multi output post body can be connected to the regulator, one of the reasons such "off the co2 cylinder" setup, the regulator and its bulky post body(multiple output) can be placed to some place more secure, and you can figure out rest of the good reasons depends on your need.

the regulator can be connect to this protocol station directly(undetachable), or through a CGA320 adapter(regulator detachable)



do not have a complete picture of my co2 work station atm, but from these two pictures you can see my personal co2 work station where the swagelok and concoa regulators connect to:



I can work on three co2 systems at the same time.



as Jeff mentioned, the protocol station is not cheap, but all the parts in our high end co2 system are not cheap neither, we can have them build because these parts are cheap enough if we know what and where to find the parts, and last, know how to make them work..
 
#22 ·
and after 4 years, to answer the original question of this thread, my answer is "yes", but only use the high pressure rating hose and the supporting station for such regulator-off-the cylinder-mounting purpose.

for off-cylinder mounting, there is pressure regulator panel we can use as well....
 
#24 ·
In some ways the higher pressure may help but in other ways it also has a downside. What I first look at is what pressure is going to work best for the type diffusion I will be using and that does require all diffusers on the same reg to be moderately the same pressure, for instance all reactors at low pressure or all ceramic, etc. at high pressure.
I do not like the ceramic, etc for the amount of fuss they require to keep them clean and working at a stable rate. I can also mass produce Grigg's style reactors in one size which serve all the different size tanks I have tried. Buying PVC pipe in ten foot and small parts in bags of ten is much more cost effective than bought separately. I can easily cut the cost from $20 to $10 when mass produced and it is always handy to have a few to pull out for trading "value added" deals!
So I favor low pressure but it also avoids some issues like buying higher cost /higher pressure fittings and tubing. I run at ten PSI which lets me use simple airline tubing on 10-32 barb fittings than come in less than a dollar each and it lets me be much more versatile in location and placement as it also lets me move away from mounting the bubble counter or flowmeters on the reg where they break so easy.
So factor, not so easy to see, is the way higher pressure tends to make tubing expand (balloon?) as the pressure is on/off. This ballooning makes the settings tend to creep more but also tends to make any movement in the tubing try to creep out of fittings, even when compression fittings are used and barb fittings are totally out for higher pressure as they blow off too easy.
So it gets down to what one wants to get done. I want cheap,easy and workable over the long term, so I go with plastic from the output of the reg and solenoid, use the much cheaper and simple to mount Fluval bubble counter or flowmeters and low pressure.
Others who want all metal may go for stainless and more appearance concerns. I have Swaglok dealers here in the local area but I find I can get the parts and build a new system in less time than it takes to ship in parts for a different setup.
It gets down to personal preference on what we each find works best for what we do.
 
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