Does anyone know where we a CNG fill up station is in NY? We are purchasing a boat and cannot find one.
CNG
- Thread starter ncleary1225
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I hope this helps: Public Compressed Natural Gas (CNG) stations and prices in New York, NY (cngprices.com)
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You will need to buy or assemble a CNG fill adapter to be able to fill a typical boat CNG cylinder from a commercial CNG fill station. They operate at a pressure of over 3000psig and your boat tank is probably closer to 2000 or 2400 psig or so. You may or may not be able to use the commercial station since the pressure exceeds the rated pressure of your tank. In addition, you tank needs to be current on its pressure certification.
All that being said, its not really difficult to assemble a fill adapter and to fill the tank. Its a little "scary" at first. The key is to have a "throttle valve" in the adapter before it gets to the fill gauge and tank so you can crack it open and fill slowly. Otherwise it will fill very very quickly and it heats up when you fill quickly and its easy to overshoot the pressure allowed by your tank. All your fittings and components of the fill adapter you assemble or build should be rated at or above the pressure of the fill station so 4000 psig rated components is a must.
Here is a picture of my adapter. You are fully and totally responsible for safety of your assembly and I take no, zero, nada, responsiblity for what you buy or build.
All that being said, its not really difficult to assemble a fill adapter and to fill the tank. Its a little "scary" at first. The key is to have a "throttle valve" in the adapter before it gets to the fill gauge and tank so you can crack it open and fill slowly. Otherwise it will fill very very quickly and it heats up when you fill quickly and its easy to overshoot the pressure allowed by your tank. All your fittings and components of the fill adapter you assemble or build should be rated at or above the pressure of the fill station so 4000 psig rated components is a must.
Here is a picture of my adapter. You are fully and totally responsible for safety of your assembly and I take no, zero, nada, responsiblity for what you buy or build.
Smokey hi
I have a CNG system with four cylinders.
I have the adapter which came with the boat when I bought it this past April.
I finally found a self service station to refill in Mulberry Florida, 2:30 hs drive from where my boat is.
I went there and tried to refill on my own. I didn't know everything you wrote here.
Bottom line it took seconds to reach 3500-4000 psi (it got hot too) but the reading in the station dispenser was about one gallon in GGE units!
I don't know if that's the capacity for a cylinder about 30-35 inches hight x 7-9 inches diameter. In fact I couldn't find a reference online for its capacity.
How can I know the cylinders capacity in GGE (Galon of Gasoline Equivalent) which is the volume unit used at the CNG station?
Then I tried to hookup the regulator to the cylinder (male-female type of connection) and dispite tightening very well, when I open the valve, gas comes out very strong. The seal is not good.
Does the connection need a gasket or anything like that?
Where online can I get it?
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Instead of being concerned with finding a CNG source ( which seems to be a vanishing commodity), and trying to make a risky DIY adapter, why not convert to propane cylinders? Its fairly easy to change the stove fittings from one to the other, and any other device you may have. People who own home gas grilles have that done often..
Hi and thanks for your comment.
I didn't build the adaptor. It's what is supposed to be. It comes with a 4000 psi Gauge
I did think about many times to change, and also I am aware of your suggestion of changing the stove fittings. It is indeed much easier to do what you say. I lived many years using propane canisters in my house when I lived in South America where electric was very expensive and Natural Gas was not available for homes.
The problem I have with Propane is that it's a much higher risk than CNG. Propane is explosive while CNG is flammable.
Propane is lighter than air and if you don't have a proper outside instalation, if there is a leak it accumulates in your bilge being heavier than air. That's very risky.
Natural Gas is lighter than air, if there is a leak it goes up and escapes through any vent into the atmosphere.
For this reason I chose to stick to CNG.
Most boats (if not all) with Propane instalation have an outside Compartment with a drain out of the hull. My boat, a Morgan 384 doesn't have it and that means keeping canisters on the deck, not a great choice.
@Joshua770: Until you know more about your tanks and regulator and related CNG pressures I would suggest you do not try to refill on your own any more. It can be done safely but you need to know the parameters, risks and what you arer doing before you do it. Just because you have a 4000 psi gauge doesn't mean you should be slamming 3500 or 4000 psi into your tanks.
Can you post pictures of your tank(s), valves and regulator? If they are similar to what others here have you might be able to get some help.
p.s. "When compressed to 3,600 psi, one GGE requires .51 cubic feet of space in a CNG tank". You can do the math on the gallon equivalent for your tank size.
Can you post pictures of your tank(s), valves and regulator? If they are similar to what others here have you might be able to get some help.
p.s. "When compressed to 3,600 psi, one GGE requires .51 cubic feet of space in a CNG tank". You can do the math on the gallon equivalent for your tank size.
If it were just a matter of changing the stove jets it could be easy and inexpensive. A lot of the CNG stoves are old though and parts can be difficult or impossible to find. That combined with the related solenoid valve, switches, thermocouples, vents and isolated lockers that are needed in a switch to propane are what keep a lot of people sticking with CNG.
Thank you so much for your advice.
indeed I was a bit scared when I filled the tank and I didn't let I go beyond 1 GGE which literally took seconds to fill in. The CNG station has a capacity of 3600 PSI.
I've been trying to load my pictures from the app in my phone but for some reason it doesn't work.
@Joshua770
Where it says 3AA2250 means the rated pressure is 2,250 psi. I would be very nervous filling it to anything more than that. There are some rules that say the rated pressure is at 70 degrees or something like that and if the tank is hot from filling it is okay to overpressurize it to a certain extent (but never over 125%) as long as it drops to no more than the rated pressure after cooling down to 70 degrees.
Where it is stamped in red "12 10" means it was last inspected / hydro tested in December 2010. My understanding of the rules are that the tanks need to be tested at least every five years so unless there is another, more recent, stamp it is way out of date.
I get my tanks tested at a gas supplier that does hydro testing on their site. About $25 per tank.
See Smokey73's post #3 about an adapter with a "throttle valve". I think you definately want that. Otherwise you have to be very quick to shut off the pump before getting too much pressure in the tank. I would not use an adapter without the throttle valve. I wouldn't even want to be standing around someone using an adapter without one. A friend of mine does and it makes me nervous just hearing him talk about it. You have seen how fast the pressure rises.
My regulator appears almost identical to yours. I don't use a gasket. When attaching the regulator to the tank I make sure the mating surfaces are clean and when doing the final tightening I let the regulator twist a bit, maybe an eighth of a turn, as I'm snugging up the nut. I usually get a good seal but test it by turning on the gas to pressurize the system then turning off the gas and seeing how long it takes for the pressure gauge to go down. If it's an hour or more I figure that is good enough.
PS: You said "The problem I have with Propane is that it's a much higher risk than CNG. Propane is explosive while CNG is flammable."
I don't think that is correct. I don't know for sure but I assume CNG is very explosive. One of the safety factors is that it is lighter than air and will dissapate rather than pool. In an enclosed compartment it could still concentrate and I assume explode.
I have read this "...the average person can detect odorized natural gas at concentrations as low as 0.3 percent. ... for combustion to occur, natural gas requires a concentration of at least five percent. In other words, a driver will detect the smell long before combustion conditions are met." So use your nose.
PPS: Note that the gauge on your regulator only goes to 3000 psi. I might not want to attach that to a tank that had as much pressure you suggested you might have put in your tank.
NB: Nothing here should be construed as my giving advice or suggesting that you should fill your own tanks. This is just to relate my experience and suggest you do your own research before making any decisions about doing so.
Where it says 3AA2250 means the rated pressure is 2,250 psi. I would be very nervous filling it to anything more than that. There are some rules that say the rated pressure is at 70 degrees or something like that and if the tank is hot from filling it is okay to overpressurize it to a certain extent (but never over 125%) as long as it drops to no more than the rated pressure after cooling down to 70 degrees.
Where it is stamped in red "12 10" means it was last inspected / hydro tested in December 2010. My understanding of the rules are that the tanks need to be tested at least every five years so unless there is another, more recent, stamp it is way out of date.
I get my tanks tested at a gas supplier that does hydro testing on their site. About $25 per tank.
See Smokey73's post #3 about an adapter with a "throttle valve". I think you definately want that. Otherwise you have to be very quick to shut off the pump before getting too much pressure in the tank. I would not use an adapter without the throttle valve. I wouldn't even want to be standing around someone using an adapter without one. A friend of mine does and it makes me nervous just hearing him talk about it. You have seen how fast the pressure rises.
My regulator appears almost identical to yours. I don't use a gasket. When attaching the regulator to the tank I make sure the mating surfaces are clean and when doing the final tightening I let the regulator twist a bit, maybe an eighth of a turn, as I'm snugging up the nut. I usually get a good seal but test it by turning on the gas to pressurize the system then turning off the gas and seeing how long it takes for the pressure gauge to go down. If it's an hour or more I figure that is good enough.
PS: You said "The problem I have with Propane is that it's a much higher risk than CNG. Propane is explosive while CNG is flammable."
I don't think that is correct. I don't know for sure but I assume CNG is very explosive. One of the safety factors is that it is lighter than air and will dissapate rather than pool. In an enclosed compartment it could still concentrate and I assume explode.
I have read this "...the average person can detect odorized natural gas at concentrations as low as 0.3 percent. ... for combustion to occur, natural gas requires a concentration of at least five percent. In other words, a driver will detect the smell long before combustion conditions are met." So use your nose.
PPS: Note that the gauge on your regulator only goes to 3000 psi. I might not want to attach that to a tank that had as much pressure you suggested you might have put in your tank.
NB: Nothing here should be construed as my giving advice or suggesting that you should fill your own tanks. This is just to relate my experience and suggest you do your own research before making any decisions about doing so.
Richard thank you so much.
Finally I know how to read the engravings in the tank.
I'll take safety measures based on your information. They make a lot of sense.
And please don't worry. Everything you wrote is to lower the risks, nothing to make it riskier.