A propane tale September 03, 2014, 12:16:01 pm Yahoo Message Number: 148424My wife and I were camping in the Eastern Sierras last week when we had a strange experience. We both had sinus problems due to colds/allergies. Going to bed that night, I awoke about 2:00-am with a very bad headache and stuffed up head. I got up and took something for it. Later my wife had a bad headache too. Waking early, I still had the headache but my head had cleared a bit, enabling me to catch an very faint occasional whiff of propane. Getting dressed, I went out side and found the propane regulator was leaking with a noticeable hiss. The primary diaphragm in the regulator had ruptured, allowing several gallons of propane to slowly leak out overnight.With the escape hatch open and the bath Fantastic fan on, raw propane had been pulled into the interior all night, leading to a long term exposure to the propane, the cause of both of our headaches. The saturation level never reached the threshold for the propane detector to alarm. Propane detector only measure the existing level, not measuring the accumulated exposure, the way good carbon monoxide detectors do.I shut the propane off and then opened the windows and turn the fans on to ventilate the interior and within an hour of so, both of or headaches disappeared. The only advice I can give is to pay attention to how you feel. Both of our headaches were unlike any we had before. Our LD's propane detector is less than two years old and appears to be working properly. The propane regulator had been replace a couple years ago. this should not be an age-related problem. A propane detector that has the ability to measure accumulated exposure would be the best warning system but I do not see this type of detector available for RV use.Larry
Re: A propane tale Reply #1 – September 03, 2014, 02:04:22 pm Yahoo Message Number: 148428Thank you for taking the time to report this experience. First, I trust that both of you are well and without lasting effects. I hope so. We have a rear bath and often operate exactly as you describe. My understanding is that propane is heavier than air, which is why the detector is mounted at floor level. If that is true, do you have a hypothesis as to how the hatch intake on the roof (with negative pressure due to the fan exhaust draw) would be able to draw propane about 9 feet up and then across to he center of the roof to the hatch? Do we overestimate the heavier-than-air effect and underestimate the drawing power of the exhaust fan? It would seem so. FYI, I told Vince once that I had wired an installed whole-house inverter to the fridge, so it would operate on AC, allowing us to shut off the propane when traveling (and relieving us as well of remembering to shut it off before entering a gas station). He maintained that shutting off the propane while driving is unnecessary, as modern tanks are designed to shut down automatically if the line is ruptured. He needs to hear your story.Thanks again for alerting us. Ted
Re: A propane tale Reply #2 – September 03, 2014, 03:07:39 pm Yahoo Message Number: 148429"My understanding is that propane is heavier than air, which is why the detector is mounted at floor level. If that is true, do you have a hypothesis as to how the hatch intake on the roof (with negative pressure due to the fan exhaust draw) would be able to draw propane about 9 feet up and then across to he center of the roof to the hatch?"TedThe wind came up frequently in small gusts during the night, possibly whipping up the pool of propane. We also had the driver door window down about an inch. The propane tank is located just to the rear of the driver's door, the fan could have pulled propane in through the open window. It was faint enough that neither of us noticed it during the night or concentrated enough to set off the detector. What was most notable was the type and severity of the headaches, Neither of us had ever had a headache of this type.The rupture safety device, built into the propane's tank outlet valve, operates when flow exceeds a calibrated rate. This leak obviously was below the valve's threshold. What concerns me more is why the regulator failed when it's only a year old, a Camco model, bought on Amazon. The only replacement I could find locally was another Camco regulator. We did have the propane tank filled the day before and the tech seemed to do it right. I was surprised to see 7-gallons pumped in less than a minute, much faster than our local place.Larry
Re: A propane tale Reply #3 – September 03, 2014, 03:58:15 pm Yahoo Message Number: 148430We did have the propane tank filled the day before and the tech seemed to do it right. I was surprised to see 7-gallons pumped in less than a minute, much faster than our local place. --- Larry, do you think that it's possible that the OPD valve "failed" and the guy overfilled the tank? Might the resulting overfill pressure have caused the regulator rupture? The "speedy" fill rate puzzles me; might the regulator *already* have been blown out when he filled and because your "smeller" was off due to ambient "mercaptan" stink and having a cold/allergies, you didn't notice?Please post when you figure out why the regulator ruptured; one would think that is the thing was faulty in the first place, it would have blown out long before this. I don't know who makes the Camco brand two-stage regulators, but Manchester Tank makes the ASME tanks on our rigs (and most others!) and Pro Tank might be worth a call, too.http://www.protanksupply.com/propane-regulators.asphttp://www.mantank.com/products/rvproducts.htmJoan
Re: A propane tale Reply #4 – September 03, 2014, 04:37:41 pm Yahoo Message Number: 148431Propane is about 2.5 times heavier than air. It has a expansion ratio of around 270:1. It's not toxic but can displace oxygen.
Re: A propane tale Reply #5 – September 03, 2014, 07:13:04 pm Yahoo Message Number: 148435"We have a rear bath and often operate exactly as you describe. My understanding is that propane is heavier than air, which is why the detector is mounted at floor level. If that is true, do you have a hypothesis as to how the hatch intake on the roof (with negative pressure due to the fan exhaust draw) would be able to draw propane about 9 feet up and then across to he center of the roof to the hatch?" The molecular weight of air is about 29 g/mol, that of propane about 44 g/mol. While the propane would settle below the air with no flow velocity, all bets would be off given any drafts, given the close mass density of the two. This just shows that relying on one safety check is no guarantee.Steve
Re: A propane tale Reply #6 – September 04, 2014, 02:20:06 am Yahoo Message Number: 148446Well, that changes everything. What I find particularly interesting (and disturbing) is that the amount inhaled was enough to give you severe headaches, but not enough to allow you to smell it or to trigger the detector alarm. I had no idea that a significant amount could be present without smelling it. Ted
Re: A propane tale Reply #7 – September 04, 2014, 12:19:14 pm Yahoo Message Number: 148448" I had no idea that a significant amount could be present without smelling it"TedBoth my wife and myself were suffering from summer head colds/allergies, so our sniffers were not up to par. Normally, my wife's super-nose would have noticed it long before me.You can bet I will not be leaving the driver's door window open at night anymore, the most obvious entry point. With the bath Fantastic fan running, it would be easy for the raw propane to get sucked into the interior. The breezy conditions would vary the amount entering. It was a rare situation that may never happen to us again.Larry
Re: A propane tale Reply #8 – September 04, 2014, 05:52:08 pm Yahoo Message Number: 148461" I was surprised to see 7-gallons pumped in less than a minute, much faster than our local place".Man, that is really a "fast fill" My experience has been about 1 GPM. Maybe this place has a super high pressure pump of some type, If so is it is possible that the high pressure applied to the tank ruptured the diaphragm, or maybe just "cracked" it a bit. I assume that the was not a Ferrelgas or Amgas retail outlet?Doug
Re: A propane tale Reply #9 – September 04, 2014, 07:00:18 pm Yahoo Message Number: 148464is it is possible that the high pressure applied to the tank ruptured the diaphragm, or maybe just "cracked" it a bit. ---- That was one of my thoughts, too, Doug. (Post #148430) I have never experienced an LPG fill at a rate even close to the speed that Larry described. Joan
Re: A propane tale Reply #10 – September 04, 2014, 07:50:28 pm Yahoo Message Number: 148466I guess it's a good reminder to turn the propane off before filling. I hadn't realized a need before hearing about this but I will from here on.
Re: A propane tale Reply #11 – September 04, 2014, 08:23:30 pm Yahoo Message Number: 148468"If so is it is possible that the high pressure applied to the tank ruptured the diaphragm, or maybe just "cracked" it a bit. I assume that the was not a Ferrelgas or Amgas retail outlet?"DougNo, it was at a fishing resort at Twins Lakes, above Bridgeport, Ca. He was filling several 25-gallon tanks, used by local cabin owners when I showed up. Maybe the pump has a high-volume mode for large tanks. I had never seen propane or natural gas pump with such a high volume rate, except for LNG fueling stations.Anyway, it has been at the back of my mind that during the filling the tank was possibly over pressurized or some kind of hammer occurred, damaging the primary stage regulator.. I will in the future close the main tank valve, never have in the past but have always made sure the propane appliances are turned off.Another case of whatever doesn't kill you, makes you stronger (or smarter)? We'll see.Larry
Re: A propane tale Reply #12 – September 04, 2014, 09:34:24 pm Yahoo Message Number: 148471I would be very surprised if the truck's pump did NOT have a high-volume mode; otherwise, the guy would never get his daily multiple-tank route done! I bet your tank got a warp-speed gas blast that blew the innards of the defenseless little regulator!
Re: A propane tale Reply #13 – September 05, 2014, 05:51:10 pm Yahoo Message Number: 148493Based on past experience, Art and I feel you were very lucky that a spark did not set off a fire - either turning on or off the fans. Sandy VT
Re: A propane tale Reply #14 – September 05, 2014, 05:56:21 pm Yahoo Message Number: 148494I know that the "propane filler" is supposed to make sure that the propane outlet valve is closed. However, I have seen this action ignored many times. When I get propane I now always do three things: open the compartment door, close the outlet valve, and remove the cover from the "propane fill" connector. Then repeat the process when the fill is completed. I also watch to see if the fill hose is properly attached and if the "vent valve" is opened. I have asked more than one "certified, card carrying propane attendant" if the really know what the H___ they are doing. Most of them really know, but cut corners because "it won't hurt anything."Doug
Re: A propane tale Reply #15 – September 06, 2014, 02:28:04 pm Yahoo Message Number: 148505Doug: exactly what I do! Open the door, shut the valve and pull the fill port cover.
Topic: A propane tale (Read 28 times)
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Topic: A propane tale (Read 28 times)
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