dartmouth01 Report post Posted December 16, 2016 (edited) Hi guys, so desperate situations call for desperate measures. We've been travelling in single digit temps or below for the past week, as we cross the country to get to Maine for the holidays. If I we were standing still, I would be able to keep the rig warm enough for the water system to work even in these temps (skirting, heat lamps, etc) but driving in these temps are requiring some more creative thinking. I have winterized the water pipes, but we still use jugs to flush the toilet, etc. I have heated tanks, but the dump valves were poorly laid out and there are exposed waste pipes and dump valves. Even mixing in a couple gallons of RV antifreeze doesn't keep the valves and exposed pipes from freezing (RV antifreeze even crystallizes at these temps, I've found), so I'm thinking of adding rubbing alcohol into the waste tanks to keep them from freezing over, and hopefully the valves as well. Any negatives to this besides cost? Thanks! Edited December 16, 2016 by dartmouth01 Quote Share this post Link to post Share on other sites
Second Chance Report post Posted December 16, 2016 Isopropyl alcohol (rubbing alcohol) is flammable... ignites easily and burns nicely. I wouldn't put anything flammable in a holding tank in my rig. Completely draining the tanks and adding several gallons of RV antifreeze (check the minimum temp to which the brand protects) would be preferable. Rob Quote Share this post Link to post Share on other sites
gjhunter01 Report post Posted December 16, 2016 How about some heat tape used around the valves and exposed piping? You could even plug it into a inverter while traveling or just wait until parked to thaw everything out. I would caution what you put into your tanks, especially anything toxic that might harm a septic system. Greg Quote Share this post Link to post Share on other sites
dartmouth01 Report post Posted December 16, 2016 Already found that -50 degrees antifreeze doesn't work, still freezes at full concentration (doesn't burst till -50 tho). So when mixed with water in the tank, the effectiveness is further reduced. The major ingradients of rv antifreeze are alcohol, propylene glycol, and water, so I am thinking I'll just up the alcohol concentration, unless a source of propylene glycol is available readily and not too expensive? I also thought of the flammable issue but of it is mixing with water in the tank, how much risk is there? Quote Share this post Link to post Share on other sites
dartmouth01 Report post Posted December 16, 2016 I may end up trying this, though currently I don't have an internal inverter system, and even running power to the heat tape would require an extension cord outside while driving down the road. I'm inclined to try alcohol first, I've read antedotal evidence that would support my idea, so I may just be a guinea pig. This is not a long term solution, just something I would need to do when the temps drop down to near zero, and rv antifreeze won't cut it. How about some heat tape used around the valves and exposed piping? You could even plug it into a inverter while traveling or just wait until parked to thaw everything out. I would caution what you put into your tanks, especially anything toxic that might harm a septic system. Greg Quote Share this post Link to post Share on other sites
Randyretired Report post Posted December 16, 2016 Propylene glycol is used in solar hotwater systems and is readily available. If you were near me I have 5 gallons in my garage but that is in Colorado. Quote Share this post Link to post Share on other sites
Barbaraok Report post Posted December 17, 2016 Already found that -50 degrees antifreeze doesn't work, still freezes at full concentration (doesn't burst till -50 tho). So when mixed with water in the tank, the effectiveness is further reduced. The major ingradients of rv antifreeze are alcohol, propylene glycol, and water, so I am thinking I'll just up the alcohol concentration, unless a source of propylene glycol is available readily and not too expensive? I also thought of the flammable issue but of it is mixing with water in the tank, how much risk is there? Actually, full strength will not provide -50° protection. That is what you get when mixed 50/50 - - it is called colligative properties, but essentially the more particles in the mixture the greater the protection. Isopropanol is not what you want to use, you want the propylene glycol - has more OH groups which helps prevent water from forming ice crystals. Barb Quote Share this post Link to post Share on other sites
dartmouth01 Report post Posted December 17, 2016 Thanks Barb. Anyone know where I could obtain propylene glycol? Solar shop sounds like an option, guess it isn't something stocked at auto zone or home depot? Quote Share this post Link to post Share on other sites
Randyretired Report post Posted December 17, 2016 Amazon has it and I have seen it on ebay Quote Share this post Link to post Share on other sites
skp51443 Report post Posted December 17, 2016 Generic Miralax can be fairly cheap in an emergency, ordering the powder/liquid is cheaper if you have time. As Barb suggested don't add too much, just a small amount and add more as you add water. https://smile.amazon.com/s/ref=sr_pg_2?rh=i%3Aaps%2Ck%3Apolyethylene+glycol&page=2&keywords=polyethylene+glycol&ie=UTF8&qid=1481949026&spIA=B00KDOT734,B00RC2FHPW Quote Share this post Link to post Share on other sites
dartmouth01 Report post Posted December 17, 2016 Miralax? Interesting, clears blockages in multiple ways, eh? Thanks, I bet walmart has that on the shelf, may come in handy in a couple days. It warms up in Cinncinati tomorrow but then back to cold temps as we head north. Quote Share this post Link to post Share on other sites
oscarvan Report post Posted December 17, 2016 Even though the "pink" turns slushy, it is still a long ways from turning solid and doing any damage. I have winter camped and used 50/50 in gallon jugs as the flushing agent. That way I don't have to worry about what the mixture is down there. As far as flammables down there....... I think the methane concentration I create is far more dangerous than some rubbing alcohol. Quote Share this post Link to post Share on other sites
Ray,IN Report post Posted December 19, 2016 (edited) Hi guys, so desperate situations call for desperate measures. We've been travelling in single digit temps or below for the past week, as we cross the country to get to Maine for the holidays. If I we were standing still, I would be able to keep the rig warm enough for the water system to work even in these temps (skirting, heat lamps, etc) but driving in these temps are requiring some more creative thinking. I have winterized the water pipes, but we still use jugs to flush the toilet, etc. I have heated tanks, but the dump valves were poorly laid out and there are exposed waste pipes and dump valves. Even mixing in a couple gallons of RV antifreeze doesn't keep the valves and exposed pipes from freezing (RV antifreeze even crystallizes at these temps, I've found), so I'm thinking of adding rubbing alcohol into the waste tanks to keep them from freezing over, and hopefully the valves as well. Any negatives to this besides cost? Thanks! Use RV anti-freeze, it's the cheapest protection you can buy. Some brands protect to -50F, and on sale cost $1.99/G at Menards. I always buy a case each fall; use about 2.5G if I winterize, and carry 2G for holding tank protection until we get far enough S to de-winterize. I pour 1G into each holding tank first, that mostly lays down in the valve plumbing, which prevents freezing. The sloshing from driving mixes added contents with it. Don't believe the folks who say RV anti-freeze is toxic or harms the environment. You eat the active ingredient every day in processed food. SDS for Peak RV anti-freeze Edited December 19, 2016 by RayIN Quote Share this post Link to post Share on other sites
dartmouth01 Report post Posted December 19, 2016 I used rv antifreeze. It still froze @ 0 degrees. As other have mentioned, it will turn slushy, tho it won't burst till -50. When mixed with waste water as well, it gets diluted and freezes faster. I'm out of the super cold for now (mid 20s now) but I'm trying out mixing propylene glycol in powder form ( miralax generic from walmart) to see what happens. Quote Share this post Link to post Share on other sites
skp51443 Report post Posted December 19, 2016 If using liquid antifreeze in the holding tanks you might want to go with concentrate instead of pre-mixed, that would take less volume to get the same level of protection. https://smile.amazon.com/s/ref=nb_sb_noss?url=search-alias%3Daps&field-keywords=concentrate+RV++antifreeze Quote Share this post Link to post Share on other sites
slackercruster Report post Posted December 27, 2016 I've used window diluted washer fluid in a pinch, but only in the traps and cassette toilet tank. Quote Share this post Link to post Share on other sites
oscarvan Report post Posted December 28, 2016 ZERO? Holy cow...... Quote Share this post Link to post Share on other sites
noteven Report post Posted February 15, 2017 Methanol will mix with water. I forget what ratio will freeze at what temperatures.... Quote Share this post Link to post Share on other sites
Sehc Report post Posted February 16, 2017 If you keep your holding tanks empty, any antifreeze will work. Any rubbing alcohol mixed with water will freeze. https://smile.amazon.com/Safe-Anti-Freeze-Coolant-Year-Green/dp/B001444SCM/ref=sr_1_fkmr0_2?ie=UTF8&qid=1487285980&sr=8-2-fkmr0&keywords=evirmental+safe+antifreeze+coolant Quote Share this post Link to post Share on other sites
