Texman 182g Mods

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Insulating the fresh water tank discussion:

Is it really necessary and/or beneficial to this project? 
The tank will be the last to freeze.  But if insulated, it will save fuel and reduce cycle times thus saving amp hours.  so, if testing results indicate that the recirc system operates within an acceptable energy usage range without insulation, then no insulation needed. Unless you just would FEEL better having done it. (me)
If insulating is to be done, here are what is see as viable options and their pros/ cons:
Spray Foam-Pros: R value, total encapsulation, closed cell so no water penetration or absorption.  
Cons: Ugly, subject to road grime buildup, costly, messy application, impairs serviceability of the area encapsulated (which there shouldn't be any)  needs protection IMO

Rigid Insulation Board-Pros: cheap, good R values, easy to form, serviceable
Cons: must be protected, attachment to pod problems, rigid 

Closed Cell Foam Insulation sheets(kflex)-pros: flexible, good R values, easy to work with and form, serviceable.
Cons: mid priced (less than $100 to cover) needs protection from road debris (not durable) attachment to pod problems

Protection Options (to cover the above options): 
Sheet metal-use a local sheet metal fabricator to build a shell to attach to the underbody framing.  Pros: fairly inexpensive (i think) durable using galvanized, neat appearance, should be easy to attach if properly fabricated by using self drilling screws into the tank framing. fairly serviceable. it would cover any of the above insulation options.
Cons: Cost,  not water proof (probably have small holes at corners) 

Heavy EDPM (40-80mil) pros: easy to form and attach using self tapping screws and a rigid piece along attachment point to reinforce edges.  Cheap. waterproof, serviceable
Cons: would being waterproof cause condensation buildup? need weep holes ? not beautiful

40 mil PVC (shower pan liner) pros: cheap, easily sourced, same as EDPM advantages
Cons: Same as EDPM cons

TPO Forgot this one 

What are the thought on these options or any i have not mentioned?  
Thanks. 

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texman Members Profile Send Private Message Find Members Posts Add to Buddy List Senior Member Joined: 24 Jul 2014 Location: TeXas Online Status: Offline Posts: 446	Topic: Texman 182g Mods Posted: 21 Feb 2019 at 10:23am
	Insulating the fresh water tank discussion: Is it really necessary and/or beneficial to this project? The tank will be the last to freeze. But if insulated, it will save fuel and reduce cycle times thus saving amp hours. so, if testing results indicate that the recirc system operates within an acceptable energy usage range without insulation, then no insulation needed. Unless you just would FEEL better having done it. (me) If insulating is to be done, here are what is see as viable options and their pros/ cons: Spray Foam-Pros: R value, total encapsulation, closed cell so no water penetration or absorption. Cons: Ugly, subject to road grime buildup, costly, messy application, impairs serviceability of the area encapsulated (which there shouldn't be any) needs protection IMO Rigid Insulation Board-Pros: cheap, good R values, easy to form, serviceable Cons: must be protected, attachment to pod problems, rigid Closed Cell Foam Insulation sheets(kflex)-pros: flexible, good R values, easy to work with and form, serviceable. Cons: mid priced (less than $100 to cover) needs protection from road debris (not durable) attachment to pod problems Protection Options (to cover the above options): Sheet metal-use a local sheet metal fabricator to build a shell to attach to the underbody framing. Pros: fairly inexpensive (i think) durable using galvanized, neat appearance, should be easy to attach if properly fabricated by using self drilling screws into the tank framing. fairly serviceable. it would cover any of the above insulation options. Cons: Cost, not water proof (probably have small holes at corners) *Heavy EDPM* (40-80mil) pros: easy to form and attach using self tapping screws and a rigid piece along attachment point to reinforce edges. Cheap. waterproof, serviceable Cons: would being waterproof cause condensation buildup? need weep holes ? not beautiful 40 mil PVC (shower pan liner) pros: cheap, easily sourced, same as EDPM advantages Cons: Same as EDPM cons TPO Forgot this one What are the thought on these options or any i have not mentioned? Thanks.
	TexMan 2015 182g 2018 Sequoia TexManMods

offgrid Members Profile Send Private Message Find Members Posts Add to Buddy List Senior Member Joined: 23 Jul 2018 Online Status: Offline Posts: 5290	Posted: 21 Feb 2019 at 12:03pm
	My thoughts: The tank would be the last thing to freeze and even if it did it probably wouldn't hurt anything, especially if it was kept pretty full (not not so full that the ice had nowhere to expand to). But as it is in the heat recirculation loop it will never have a chance to freeze anyway, since it needs to be kept above freezing or the pump supply line can freeze up. Ergo, the need to insulate it to keep the propane consumption down. I'm pretty sure it will be high otherwise, but its not going to hurt anything to wait and see. I'd add to the cons with the options where the insulation is directly attached to the tank the need to adhere the insulation to the poly tank surface, which can be problematic. A pro for these is there isn't any need to cover every inch of the tank surface, you could leave access points open for servicing fittings, sensors etc. To the cons for the ones which aren't attached add the need to create a tight seal over the whole tank against wind entry. On the spray foam, I think its around a $100 option too so probably not any different from most of the others. And personally I don't care what it looks like under there, its not like its someplace I plan to spend a lot of time . Spray on closed cell roofing has been in use for 50 years and holds up well. You can paint it if you want to, on roofs you have to to protect it from UV. Your idea of using a flexible liner of some type reminded me of another possible option. When I insulated the floor of my (elevated) house a year ago I had to do it from underneath and wanted an easy and inexpensive way to get a higher r value than using the pink stuff. I stapled landscape cloth between my floor girders and filled the entire 20 or so inch space with blow in insulation on top of that. Then installed the plywood underpinning. So how about a "bag" of landscape cloth filled with some type of loose fill water resistant insulation, like maybe polystyrene packing peanuts? That would be very inexpensive, give a high r value, and be removable in future just by pulling the bag and insulation off and throwing it away.
	1994 Chinook Concourse 1995 RV6A Experimental Aircraft 2015 Rpod 179 - sold

lostagain Members Profile Send Private Message Find Members Posts Add to Buddy List Senior Member Joined: 06 Sep 2016 Location: Quaker Hill, CT Online Status: Offline Posts: 2587	Posted: 21 Feb 2019 at 12:33pm
	What about fabricating a metal tray to mount under the trailer with enough space between it and the FW tank to allow insulation. Remove the tank to use as a mold [with mold release smeared all over it] and fill the space between the tank and the tray with foam insulation, then when the foam has cured, remove the tank, reinstall it, then mount the tray with the insulation below the tank. If you need access points and such you could allow for them in fabrication of the tray and application of the foam. The insulation would adhere to the tray, not the FW tank. I haven't a clue whether this would work, but it seems like a possible approach as you could fabricate the tray to be pretty tight against the underbody so it would not let in much moisture.
	Never leave footprints behind. Fred & Maria Kearney Sonoma 167RB Our Pod 172 2019 Ford F-150 4x4 2.7 EcoBoost

texman Members Profile Send Private Message Find Members Posts Add to Buddy List Senior Member Joined: 24 Jul 2014 Location: TeXas Online Status: Offline Posts: 446	Posted: 21 Feb 2019 at 1:42pm
	thanks for the feedback. do you think that condensation is a concern with the metal or "unbreathable" liners ? Water in the tank will be warmer than outside the enclosed space. I like the idea of using a liner like TPO and enclose it like you said with the peanuts or something. (good idea on peanuts BTW) I like the metal too and that is good idea to form the insulation. Not sure i want to subject myself to removing the tank, but that would work well. but it would cost more and TPO is super tough and should be easier to attach. metal could have access doors/panels which would be nice too. i think i have a source for TPO from a roofer friend. Comes in 10 ft wide rolls. he is gonna donate it so worth a shot.
	TexMan 2015 182g 2018 Sequoia TexManMods

offgrid Members Profile Send Private Message Find Members Posts Add to Buddy List Senior Member Joined: 23 Jul 2018 Online Status: Offline Posts: 5290	Posted: 21 Feb 2019 at 2:02pm
	The tank will get condensation on it overnight in warmer weather. I've seen it on mine. Insulation will reduce that a lot of course, but I'd be a little afraid of an impermeable membrane. Maybe just punch some drain holes in it?
	1994 Chinook Concourse 1995 RV6A Experimental Aircraft 2015 Rpod 179 - sold

offgrid Members Profile Send Private Message Find Members Posts Add to Buddy List Senior Member Joined: 23 Jul 2018 Online Status: Offline Posts: 5290	Posted: 23 Feb 2019 at 6:49am
	Re: using loose fill polystyrene, there is an issue with pour filling it into cavities due to static buildup. So its going to be an problem with filling an irregular cavity in bag surrounding the water tank with beads or peanuts too. The beads are going to have to be blown in to get a nice tight pack I think. A shop vac used as a blower could work, or you could make up a gun using compressed air to draw the beads in at a venturi. Here's a commercial gun that does that but its not cheap. https://www.amazon.com/ROYAL-PneuVac-Air-Gun-Model/dp/B00207I9MM https://www.youtube.com/watch?v=Z5BIzGa-EAo And a home made gun using a show vac as a blower. https://www.youtube.com/watch?v=GK0-UCWwtE0
	1994 Chinook Concourse 1995 RV6A Experimental Aircraft 2015 Rpod 179 - sold

lostagain Members Profile Send Private Message Find Members Posts Add to Buddy List Senior Member Joined: 06 Sep 2016 Location: Quaker Hill, CT Online Status: Offline Posts: 2587	Posted: 23 Feb 2019 at 7:13am
	What about using polyurethane rigid foam. You could spray it from cans and to ensure complete coverage, put a few access holes into the base or "tray" that will be mounted below the FW tank. The hardest thing with that kind of foam is to get it evenly applied so that you don't have excessive expansion that could distort the FW tank. The problem I see with polystyrene beads is that it's hard to keep them where you want them once you spray them inside and there is no way to bond them to one another.
	Never leave footprints behind. Fred & Maria Kearney Sonoma 167RB Our Pod 172 2019 Ford F-150 4x4 2.7 EcoBoost

offgrid Members Profile Send Private Message Find Members Posts Add to Buddy List Senior Member Joined: 23 Jul 2018 Online Status: Offline Posts: 5290	Posted: 23 Feb 2019 at 7:29am
	Spray on two part closed cell polyurethane foam was my original suggestion and is still my favored approach. But texman is concerned about it for several reasons he has identified in an earlier post. You don't want to use plain old open cell "great stuff" type foam, it will become water logged. And it will be important to test to be sure it adheres to the polyethylene tank, its hard to get anything to stick to that. If the tank is filled with water when you spray it I can't imagine there would be any tank distortion, its going to be like spraying foam on a rock
	1994 Chinook Concourse 1995 RV6A Experimental Aircraft 2015 Rpod 179 - sold

texman Members Profile Send Private Message Find Members Posts Add to Buddy List Senior Member Joined: 24 Jul 2014 Location: TeXas Online Status: Offline Posts: 446	Posted: 23 Feb 2019 at 9:16pm
	I
	TexMan 2015 182g 2018 Sequoia TexManMods

texman Members Profile Send Private Message Find Members Posts Add to Buddy List Senior Member Joined: 24 Jul 2014 Location: TeXas Online Status: Offline Posts: 446	Posted: 23 Feb 2019 at 9:23pm

	TexMan 2015 182g 2018 Sequoia TexManMods