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bobrok
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# Posted: 22 Sep 2014 07:57pm
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I've been hesitant to post here because I thought it would be too far off-topic, but with the current direction of this thread I'm now comfortable doing so.
First off, can someone tell me the difference between type K, type L, type M, and refrigeration copper coil as related to LPG gas usage for the typical cabin needs (lights, heat, refrigerator)?
I have a brand new box with 20' of 3/8" O.D. copper coil marked "refrigeration" and I'm wondering if it is OK to use this to add line(s) to my existing 3/8" soft copper system.
Is it a little heavier- or lighter- walled? Can't find the difference and I'd like to know before I open this box.
I do have other sizing questions to follow, but I want to attack this in order; less confusion.
thanks
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MtnDon
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# Posted: 22 Sep 2014 08:29pm - Edited by: MtnDon
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Type K has the thickest wall section of the three types of pressure rated tubing and is commonly used for deep underground burial such as under sidewalks and streets, with a suitable corrosion protection coating or continuous polyethylene sleeve as required by code. In the United States it usually has green colored printing.
Type L has a thinner pipe wall section, and is used in residential and commercial water supply and pressure applications. In the United States it usually has blue colored printing.
Type M has an even thinner pipe wall section, and is used in residential and commercial water supply and pressure applications. In the United States it usually has red colored printing. It is NOT rated for LP gas.
Refrigeration tubing, also called ACR for air conditioning and refrigeration, is made to higher internal cleanliness and dehydration requirements. It comes in a coil with ends closed. It is filled with nitrogen. Refrigeration tubing is also sized differently.
K, L & M are sized by the I.D, where a 1/2" tube is 1/8" larger in the O.D., making the so called 1/2" tubing actually 5/8 O.D. The wall thickness varies from thickest being type K and type M being thinnest.
A piece of 1/2" refrigeration tubing is 1/2" on the O.D.
There is also DWV type that is not to be used under pressure. Drain Waste vent just like in ABS DWV pipe. There is also MED, for medical gasses.
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MtnDon
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# Posted: 22 Sep 2014 08:34pm
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Pressure wise I believe ACR is somewhere between K and L in a given size. That's not a guarantee but I think that is so. Since K and L are okay for most LP gas applications that should make ACR okay. Best is to check local LP regulations.
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bldginsp
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# Posted: 22 Sep 2014 09:23pm
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Toyota- you thought standard low pressure propane is 11 lbs- it's 11 inches water column, which is 6 ounces or 1/2 psi, so I learned today of google.
Seth- quoting you- Do you think I should run everything off of one small tank? One thing you can do is gang together two or more small tanks, which gives a greater ultimate flow capacity, but with your smaller needs and Costa Rica high temperatures this may not be a concern. Your idea to use a separate tank for lights makes less plumbing at the tanks, but you have to have two regulators, and more piping to the appliances instead of one run of larger pipe.
Since there are lots of parts involved and you have to bring them all, have you considered building the complete system at home so you know what you need, then disassemble it and pack it up?
If you are getting elec soon, maybe just bringing propane canister lanterns down for a year would work. They are cheap, but go through a lot of canisters. Next thread- how to refill propane canisters from a 20 lb tank.
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Turbogeno
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# Posted: 23 Sep 2014 06:04am
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I have 2 of the Mr. Heater gas lamps and had a lot of trouble getting adequate light output from them. It seemed they weren't getting enough gas and just sort of glowed orange instead of bright white. I have the correct orifices, 11" WC and short, individual 3/8" runs of copper pipe. They work OK as long as I use the preformed mantles but are not as bright as they should be. I used a brand new 100 lb. tank so maybe there was contamination in the tank or I got bad propane. I'll see what happens when I get a refill.
Thanks, Geno
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toyota_mdt_tech
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# Posted: 23 Sep 2014 10:46am
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Quoting: bldginsp Toyota- you thought standard low pressure propane is 11 lbs- it's 11 inches water column, which is 6 ounces or 1/2 psi, so I learned today of google.
Thanks bldg insp for the correction, I just remember the "11" from years ago. 
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Seth
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# Posted: 23 Sep 2014 02:08pm
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Quoting: bldginsp Since there are lots of parts involved and you have to bring them all, have you considered building the complete system at home so you know what you need, then disassemble it and pack it up? If you are getting elec soon, maybe just bringing propane canister lanterns down for a year would work. They are cheap, but go through a lot of canisters. Next thread- how to refill propane canisters from a 20 lb tank.
I'd like to try flaring at home before I get down there, but because I don't have the distances measured exactly I can't really assemble the whole thing until I get there and make some final decisions. As for bringing down propane canisters, I don't think I'd be able to get them through the airport - and it might turn out that as with many things in the country, the 'one year' I have to wait for power may well end up being a few years actually, so I'm willing to invest a bit - and the three Humphries were free.
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bldginsp
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# Posted: 23 Sep 2014 03:59pm
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What I was thinking was building the whole system at home, minus the long lengths of pipe, just short ones, but with all the appliances, fittings, etc. That's what I've done several times with copper water fittings for my water system, I assemble it dry at home, sweat what I can, but lay out all the parts on my bench. I hate driving 1/2 hour to the nearest building supply to get one part when I'm up at my place, so I get a few extras at home.
What happened with your horizontal siding? did you leave it as was installed by your carpenter?
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Seth
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# Posted: 23 Sep 2014 04:03pm
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Yeah I will definitely at least make sure I have plenty of parts - extra, even - and give a try to fitting some together before I go down. I'll only have a couple days with lots of other prep to do, but I definitely want to have everything I'll need and then some when I arrive.
As for the siding, I've been in Alaska since the end of April so haven't yet had a chance to do anything about it. According to my girlfriend who has checked on the place about once a month there has been no water leaking in - just some mold growing on my clothes and books (insane humidity down there). So, I'll certainly assess re-doing all the siding if I think I can make it happen, but seems to be holding up so far - thanks for remembering.
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bobrok
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# Posted: 23 Sep 2014 08:34pm - Edited by: bobrok
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@ MtnDon: thank you for the valuable info. I'm more comfortable now that I can use that tubing.
Also would like to continue/expand the thread just a bit more with another question.
I'm ready to install a third Humphrey propane light fixture at my cabin. After reading and re-reading this thread I'm conflicted about whether to install a trunk line or simply tee off for the new fixture.
My cabin is 20" x 20". I have a 200 lb. propane tank and the entire system from the regulator is 3/8" flare fitted and with tees added where needed. The person who built my cabin did a rather crappy job and for no apparent reason ran switchbacks and tees all over the place, hung rather haphazardly, but there are no leaks. I could literally redo my system and have tubing left over.
Now with the addition of the third fixture I am finally ready to fix the mess. The problem is (or isn't) that the LP tech who tested my system told me I had great pressure and didn't need a trunk. System was tested with everything on: heater, fridge, lights, stove, oven, water heater.
I should note here it's rare, if ever, that those appliances are used all at the same time.
Reading above and viewing those charts gives me confusion and now I am stalled on the project. Obviously it would be easier to just re-do the bad work.
Am I not realizing some advantage in having a trunk line?
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MtnDon
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# Posted: 24 Sep 2014 02:17pm
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A good sized trunk line can make it easier to add some higher use propane appliance sometime down the road. If the trunk is copper future branches are easy enough to insert by cutting and re-flaring the ends to accept a tee. For iron pipe it can be better ti install some un-used tees here and there.
I also favor a trunk that has a shut off valve where each branch line connects to the trunk line. That makes servicing any one item possible without shutting down others.
My 2 cents
As for the existing system there's 2 schools of thought. (a) don't mess with something that is working and does not leak. (b) it is nice to have everything neat and tidy and if the mess bothers you, change it.
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bldginsp
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# Posted: 24 Sep 2014 06:01pm - Edited by: bldginsp
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Bobrok-
If all your existing appliances will operate simultaneously with whatever piping you have, that's all you need and installing a trunk line won't help you. But if you plan to instal more, as MtDon said, you may need to make alterations.
Even though your present system is not leaking it sounds funky to me. I'm really strict when it comes to gas because I've heard horror stories, and flexible copper tubing carrying gas scares me to begin with. Then you tell us it's obvious the previous owner did a funk dog job of it. Well.... I'd consider replacing the whole system just for safety, but I go to extremes sometimes.
As for just adding one propane light to the system, that is pretty minimal as they use so little gas. But I'm amazed that your system uses only 3/8 tubing for stove, heater and water heater. Do each of these have their own 3/8 line that goes back to the regulator, or are there any splits or Ts? Whenever it splits, you then have multiple appliances being fed off one feeder line, and 3/8 isn't big enough to handle that many btus, or so I thought.
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bobrok
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# Posted: 24 Sep 2014 07:14pm - Edited by: bobrok
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I have one 3/8 tube beginning at the regulator. It travels underneath the cabin and then begins it's crooked, zig-zag travels.
I have not mapped out the system yet to see where my appliances/fixtures tee off, but to answer one question, I have only one line and it is quite possible that there are tees running off tees under there. That's why I want to re-do everything.
I know a total system re-do is in order and I'm going to do that; no question. My original post stems from my questioning whether or not I really need a trunk line since I've been tested to have good pressure as it is now. I can re-do the system minus the trunk line by re-using the existing tubing and tees.
And as you've said, one additional light fixture won't put much more demand on the system.
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MtnDon
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# Posted: 24 Sep 2014 08:00pm - Edited by: MtnDon
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Add up the total BTU's used if everything was on at the same time. Refer to a chart like this one. There is data for all the popular propane piping types. Determine the minimum size line for the distances involved.... Do some playing around to see if the same size would do throughout or if a trunk main would be advatageous in the future if there were additional items added.
And while you are playing with numbers be certain the regulator is up to the maximum.
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bldginsp
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# Posted: 24 Sep 2014 08:09pm
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I seriously doubt that if you did a proper gas pipe sizing calculation that your 3/8 trunk line would be anywhere near what the chart says. But, you are able to run all appliances at once with the setup as is, so this proves that the pipe sizing charts are quite conservative and you can exceed them and get by. But it could be that when you have the heater and water heater on at the same time that they are not burning correctly which could screw up the appliance eventually and/or make them operate less efficiently.
I would suggest doing a full ppe size chart and calculation to see how far off you are from the chart. If its way off I'd say you've been lucky up to this point and for peace of mind put in a minimum sized trunk line of 1/2 or 3/4" hard pipe only up to the point where the last major appliance Ts off. No problem Ting off 3/8 for the sake of the lights.
Because you have only a single 3/8 coming off the tank, all your appliances must be Td off of that. Since 3/8 ID pipe at 20 ft is supposed to be able to handle only 50k btu, you are way off. Your water heater is that at least. Your installer said you 'have good pressure', I wonder what that means, since the regulator should limit the pressure in any circumstance.
Do you know the btus of all your appliances, and the length of pipe from the furthest appliance (even if a lantern) to the tank?
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MtnDon
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# Posted: 24 Sep 2014 08:51pm - Edited by: MtnDon
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A pressure test doesn't prove the pipes have the right capacity for flow, unless the pressure test was done at the end of the pipe run with all the devices burning. Flow is by pipe size and demand (BTU/hr).
Depending on what/how the branch lines are run presently you may be able to run a main/trunk line that can connect with more or less ease to those branches. Might not be necessary to redo all the lines to the lamps for example.
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bobrok
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# Posted: 25 Sep 2014 06:13pm - Edited by: bobrok
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Quoting: MtnDon Add up the total BTU's used if everything was on at the same time. Refer to a chart like this one.
That link only returns to the forum. I would appreciate it if you could try that again.
Quoting: bldginsp ...when you have the heater and water heater on at the same time that they are not burning correctly which could screw up the appliance eventually and/or make them operate less efficiently.
My thoughts exactly. I have already decided to do a trunk line. It will actually make the job easier because I can run that, add new tees, and then switch over one appliance at a time.
Quoting: bldginsp put in a minimum sized trunk line of 1/2 or 3/4" hard pipe
I presume those charts Don referred to, in addition to my adding up the btu ratings of everything, will help me determine whether to go 1/2" or 3/4"
I like the idea of copper pipe rather than iron for the trunk since upwards in the thread somewhere its mentioned that you need to transition carefully from iron to copper. It makes sense to me to stay all copper, even if more expensive.
Edit: Hey you guys, I really do appreciate your input on this.
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bldginsp
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# Posted: 25 Sep 2014 06:22pm - Edited by: bldginsp
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I don't know about the risks/problems with connecting iron to copper in the case of gas piping- maybe your propane supplier can help you. There must be an appropriate dielectric fitting that will prevent galvanic corrosion at the connection. But I suppose you could use standard copper water pipe, I don't know if there is any code provision not to- never seen hard copper pipe used for gas.
If you choose to stay with a copper trunk line you may need a larger one to handle the total btu capacity. The charts MtDon refers to are the same ones linked to earlier in the thread- it's the code propane pipe sizing chart.
The trunk line you have now is too small. If you want to stick with copper 3/8, you could run multiple lines back to the tank, one for each major appliance, then branch off those for the lights.
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Seth
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# Posted: 25 Sep 2014 06:25pm
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Quoting: bldginsp What I was thinking was building the whole system at home, minus the long lengths of pipe, just short ones, but with all the appliances, fittings, etc. That's what I've done several times with copper water fittings for my water system, I assemble it dry at home, sweat what I can, but lay out all the parts on my bench. I hate driving 1/2 hour to the nearest building supply to get one part when I'm up at my place, so I get a few extras at home.
Well, I just went to my local hardware store and found a super-friendly lady who found everything I'd need from the propane tank to my third and final light, but it totaled up to nearly $340... much more than I was expecting... and a bit much for something that I'll only need until I get electricity next year. Given that I won't be able to find spare parts for any of it while I'm down there and the huge up-front cost, I think I'm going to either just use candles this year or see if I can convince a neighbor to let me run 12 ga. Romex wire from their house to mine. (They're probably 300' away). Anybody know much about wire capacity over that distance? I'd have about 5 incandescent lightbulbs, a small fridge, a computer to charge once in a while, and the electric shower head if possible.
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MtnDon
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# Posted: 25 Sep 2014 06:31pm
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120 VAC, 300 feet, 12 gauge wire, 5% voltage drop = maximum of 4 amps.
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bobrok
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# Posted: 25 Sep 2014 06:35pm
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@Seth, I am sorry to be walking all over your thread here with my own problems; they seem to be rather associated and I guess its OK with the mod to keep these conversations together  .
Quoting: bldginsp If you want to stick with copper 3/8, you could run multiple lines back to the tank, one for each major appliance, then branch off those for the lights.
That would be a lot of 3/8 tubing and I'd probably have to fashion some sort of manifold at the regulator end to accommodate everything. Sounds like too much work. I think I'll plan towards installing a trunk line and then separate 3/8" tees to each appliance.
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Seth
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# Posted: 25 Sep 2014 07:14pm - Edited by: Seth
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Quoting: MtnDon 120 VAC, 300 feet, 12 gauge wire, 5% voltage drop = maximum of 4 amps.
MtnDon, for a layman like me who knows nothing of amps and volts, does 4 amps max mean I can't get a lot out of that cable? I'm looking at my computer charger now, it says Input: 15A AC 100-240V 50/60hz, Output: +16.5v, 3.65 A.
Is 3.65 A the amps? Meaning I could charge my computer but not run the fridge at the same time? I found through a search that small fridges (~4 cubic feet) typically use 2 amps or less.
If you have any suggestions for how I could make this work, I'd be very interested. Thicker gauge wire? Anything I can do?
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bldginsp
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# Posted: 25 Sep 2014 08:22pm - Edited by: bldginsp
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Bobrok- sounds like a good plan. The 'proper' thing to do is a set of pipe size calcs to determine pipe sizes, but you could say that your actual installation shows quite pragmatically that your pipe sizes, as are, are functional (if funky). So upsizing with a 1/2" trunk can only improve the situation. You could use 3/4 for just the first section, to the first T, just for insurance, then 1/2 to the next Ts and 3/8 to each appliance, you'd probably be fine.
Seth- it's a shame to waste those two nice propane lights, how about setting a tank between the two of them, and running only the lines you need to the lanterns? That could remain in place as your backup lighting when the local power is out. 300 ft is a long way for an electrical feed. I think the 14 input amps is what you need to supply for your charger, not sure, seems too high. Wire costs increase dramatically as size increases, as you probably know.
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Seth
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# Posted: 25 Sep 2014 08:34pm
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Quoting: bldginsp Seth- it's a shame to waste those two nice propane lights, how about setting a tank between the two of them, and running only the lines you need to the lanterns? That could remain in place as your backup lighting when the local power is out. 300 ft is a long way for an electrical feed. I think the 14 input amps is what you need to supply for your charger, not sure.
A lot of the cost is in the tools, regulator, and tubing, and every little connector adds to it, so even if I downgraded I wouldn't really save much. And since the lamps in their packaging plus all the equipment for installation would take up quite a bit of space in my luggage also, it's just not looking like such a great idea anymore. I'll check prices in the Boston area as I move through there on the way to CR, but I don't imagine things will cost significantly less.
That's a bummer about the long electrical feed not working... looks like I may be enjoying a lot of candlelight, charging the laptop at a friends, and using a cooler and ice blocks - won't be so bad really, but we'll see. I could end up buying a generator down there.
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bldginsp
Member
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# Posted: 25 Sep 2014 09:20pm
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Small solar pc charger?
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MtnDon
Member
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# Posted: 25 Sep 2014 09:24pm
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Quoting: Seth MtnDon, for a layman like me who knows nothing of amps and volts, does 4 amps max mean I can't get a lot out of that cable? I'm looking at my computer charger now, it says Input: 15A AC 100-240V 50/60hz, Output: +16.5v, 3.65 A. Is 3.65 A the amps? Meaning I could charge my computer but not run the fridge at the same time? I found through a search that small fridges (~4 cubic feet) typically use 2 amps or less. If you have any suggestions for how I could make this work, I'd be very interested. Thicker gauge wire? Anything I can do?
The 15 amps input can not be right. My laptop AC adapter is 1.5 amps. That is maximum draw.
I was curious and got out my clamp meter. Right now the laptop battery is full and it is just coasting along on a float current. The 120 VAC draw metered at .10 amps. If the battery was down and it was charging it would still be running less than one amp IIRC.
The 3.65 amps figure is the OUTPUT of the adapter/charger. That is a higher amperage than the input as the output volts is lower.
when comparing in / out volts and amps on something, when the volts go down the amps go up. That is because Volts x Amps = Watts. Watts is the measure of the work being done. It will stay the same for any task. So if volts change up, the amps change down. And vice versa.
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Wire.....
1. The greater the wire resistance the greater the voltage drop. Longer wires have more resistance. 300 feet is long.
2.
Our electrical systems have a nominal 120 VAC. 108 VAC is the lowest voltage many devices will operate at. That would be a 10% voltage drop. For 120 VAC circuits 3 to 5% is looked at as the maximum design voltage drop. You could use that 108 volts as a theoretical maximum. That would raise the maximum current to 8 amps.
3. When the voltage being supplied to the electric device drops, the amps drawn increase. That is because the device still wants the watts it was designed for. Say 600 watts total. At 120 volts that 600 watts = 600 / 120 = 5 amps. When the voltage drops to 108 that changes things significantly. We still need 600 watts. So 600 / 108 = 5.55 amps.
If the wire size was marginal to begin with at 5 amps when the voltage drops and the amps go up the situation worsens. A nasty circle of cause and effect.
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300 feet of copper wire, even only 12 gauge is not cheap. As bldginsp mentioned the cost goes up quickly with each increase in size. For safety the wire should/must also be outdoors rated and should be trenched and buried. It quickly can get out of hand. All that effort trenching... might as well use larger wire to make the effort pay bigger dividends... that boosts the price....
If you do go for larger wire there is a point where going to aluminum makes $$-sense. The gauge needs to be larger most of the time but Al is cheaper than Cu.
~~~~~
Would it make sense to shuttle batteries back and forth? Have a set on a charger at all times and another set in use. That means a good 3 stage charger ($$) and a lot of shuttling. Also probably shortened battery life. Probably not a real good idea.
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MtnDon
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# Posted: 25 Sep 2014 09:30pm
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FYI, a good clamp meter for a reasonable price is this one from Sears Craftsman.
Good enough accuracy for most DIY work. It reads very close to the readings from my Fluke but it wanders a percentage point either way.
Funny how we transitioned from propane to electricity.
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Seth
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# Posted: 29 Sep 2014 06:06pm
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Quoting: MtnDon Would it make sense to shuttle batteries back and forth? Have a set on a charger at all times and another set in use. That means a good 3 stage charger ($$) and a lot of shuttling. Also probably shortened battery life. Probably not a real good idea.
Thank you so much MtnDon - you've taught me a lot! I'll bring all this info down there with me on Wednesday, get an accurate distance measurement to the neighbor's house, and figure something out soon enough. Thanks again, I really appreciate you taking the time to explain it so thoroughly.
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Seth
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# Posted: 29 Dec 2014 09:17am
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Quoting: MtnDon 300 feet of copper wire, even only 12 gauge is not cheap. As bldginsp mentioned the cost goes up quickly with each increase in size. For safety the wire should/must also be outdoors rated and should be trenched and buried. It quickly can get out of hand. All that effort trenching... might as well use larger wire to make the effort pay bigger dividends... that boosts the price.... If you do go for larger wire there is a point where going to aluminum makes $$-sense. The gauge needs to be larger most of the time but Al is cheaper than Cu.
Thought I'd post a little update here. Shortly upon arriving back in Costa Rica I was able to work out a deal with the church at the bottom of the hill and had them put in an additional electrical meter on their property in their name. I bought 190 meters (~620') of #4 aluminum cable (~$330) and strung it up to my house, re-did some of the electrical installation inside the house as the builders hadn't put any ground wire in any of the outlets, and after living a month and a half with candlelight I am now fully illuminated.
First electrical bill was $14. Not too shabby! I set up the bill to be automatically paid so the church never has to deal with it. I've had no trouble using power tools, recharging laptop, I've got a mid-size fridge, rice cooker, slow cooker, and an electric shower head and everything's working splendidly. Many folks in the village said I could get away with #6 cable but I'm glad I paid a bit more for #4.
It's a temporary solution until the electrical company puts posts up to my land which may or may not happen in 2015. When it does happen I'll have a much shorter distance (~30 meters) to a post and I'll have some used cable for sale.
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Seth
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# Posted: 17 May 2015 08:43pm - Edited by: Seth
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Back in AK now after 7 months at the cabin - thought I'd post a little update. Before I went down I headed to a hardware store and lined up everything I'd need for propane lighting system - it was going to be over $400. So I said 'screw it' and went down there hoping to find another way - which I did, pretty quickly.
After learning that the electric company wouldn't put posts up to my place until sometime in 2016 I had the church at the bottom of the hill ask the electric company for an additional meter in their name on their post and I bought 200 m of 4-gauge three-strand aluminum cable, strung it through the trees and connected it to my house. The cable cost less than what all the copper tubing and tools would have cost.
My account in the local bank pays the bill automatically and so it's no hassle for the church. The power arrives with strong voltage and my electric shower head gives hotter water than any shower I've ever used in that village - I think most other far-flung houses bought cheaper, thinner gauge cable and so they lose quite a bit of voltage over the distance - but not me.
The bills have been very reasonable too, from $10-15 a month. After living a month and a half without power, relying on neighbors to charge laptop and phone and store meat, it's been a whole new world having power. And next year when the electric company finally puts posts up to my land I can take down the cable, cut it to the 30 or so meters from my house to the road, and have a normal treeless setup. Woohoo!
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