T310SR Enclosed Tanks Option (with Pics)

[JohnB]

Fellow Sunliners

For those curious on what an enclosed tank option looks like on a TT by Sunline, here are pics of mine. The T310SR was only made during 2003 and 2004. So I do not know if all T310SR's had this or it was an actual option. In my case I’m glad I have it.

The tank layout is good in my opinion. The dump valves are way up inside to not have cold weather affect them. The fresh tank is right over the axle so when filled it does not add/subtract tongue weight.

The enclosure, this needs some work. I know this is considered to be an “extended season” tank enclosure but there are some things that just do not look Sunline. Mostly in craftsmanship. A little more time spent and the design would of looked/worked a lot better. In time I will update this area and feel I can then truly extend the camping season with water still on board. I have a good design start from Sunline, all I have to do is cleanup the insulation and bottom cover support, plug some big holes and redo the fresh tank drain to be an inside shut off drain spout.

I also found a few things that where in need of fixing and glad I caught it now. Here are the pics of inside:

Here is a shot of the bottom cover. It is a plastic corrugate sheet. I have seen this on many other enclosed tanks campers.


And the front area. A metal cross members blocks/creates the front and rear.


And the sheet laying off the camper


Now the insides, The slide side looking back. You can see the black tank dump valve at the end of the tank


A more central shot looking to the back


A shot looking to the front, the gray tank


A shot at the back of the enclosed area. You can see the fresh tank over the front axle


And the fresh tank with the low point pocket. I’m glad to see this. I will soon convert the side suction port to tee into the bottom drain port and gain another 3 to 5 gallons of usable water from the tank before the pump sucks air in. I did this on my T2499 and it worked very well. I could suck down to the last quart in the tank and not air lock the pump.


There is also something unique to Sunline here maybe. See the large metal strapping under the fresh tank. That is a good thing. That strapping supports the bottom of the fresh tank when you are towing with full fresh water. I have seen my friends Jayco and Skyline and those 2 campers only have thin wimpy pipe strap tape holding the fresh tank in. I would be real nervous towing with those setups, but Sunlines with this heavy tank strap, I tow often with full fresh water and no worries the tank is coming out. Both of my Sunlines have this feature. I do not know when it became standard, but it was there in 2003 and 2004.

Now here is the first OMG! . See the black tank dump handle about ready to completely unscrew it self. I fixed this with a jam nut to keep the long pull rod from coming off. I also did it to the gray tank rod. That would have been an issue if it came undone at a CG or worse rolling down the road.


Then there is this. That is the manual slide drive shaft where you can put a crank on the outside of the TT to move the slide if the motor burns out or battery is dead. 2, issues.



First the rod is wearing a hole in the side of the air duct. Second, the roll pin fell out of the rod to the motor shaft. Glad I did not have to use this. So I corrected this while was in there. I put a plastic pipe sleeve around the manual shaft to protect the duct. There was no way to move the duct. And I put a screw with double nuts/lock washer on the shaft.


This is all for now. More as improvements come.

First is added bottom insulation. I’m looking at this. Flex Foil http://www.ipcpack.com/foilbuildapp.cfm The R value pending application really high and it is friendly with wetness if it gets wet. And it is not very thick and is light. I was going to put this on as a first layer, then the plastic cover over it on the bottom.

I found this at a Jayco plant tour this summer. They use it on the bottom of there fiver’s. They claim it to have an R15 value.

Anyone ever see or use this stuff?

Hope you enjoyed the pics.

John

[Tweety]

John,
Is there heat to the enclosed tank area? Was there any insulation, or just the corragated sheet?
Pam

[frank]

Thanks for the pictures, John. I've been seriously considering enclosing and heating the two tanks on the 2363 to allow for cooler weather camping. Because of the way the tanks sit, I'm thinking of 1/4" ext grade ply boxes lined with foam..

That insulation looks interesting. Going by the example install shots and the estimated R values, it seems they are using the air pocket created by the foilbuild to gain R. The bigger the pocket created, the higher the R value. So the R15 doesn't seem too far fetched with a 4" frame channel when going by the manufacturers info there.

- Frank

[JohnB]

Originally Posted by Tweety

John,
Is there heat to the enclosed tank area? Was there any insulation, or just the corragated sheet?
Pam

Pam

The Pink foam board insulation around the sidewalls was there. About 1” thick. Maybe ¾” I did not measure but it is one of the 2.

The heat,

When the furnace runs, radiant heat from the ducts is given off heating the space. I have seen this concept on other TT makers as well. I have an ambient air temp sensor I will add to this space with a digital readout inside the TT so I can monitor what is going on. Nowhere can I find anyone to tell how cold one can go with this type of enclosed tank setup. They only say extended season. So I have to monitor and prove myself. Pending the findings if the radiant heat is not enough, I may add a very small damper off one of the ducts to pump real heat into the space. And ideally be able to control it as needed.

The first key is closing up the area a lot tighter then it is. The area has many large holes in this setup. The slide square shaft has a 5" square hole for a 1" slide shaft, the dump pipe has very large triangle shaped holes next to it. And then there is a lot of leakage around the perimeter where the large corrugated sheet attaches. If I just purely insulate better I can get by from the night freezes when day is above freezing. Which is really all I’m after. I will not attempt it if night and day are well below freezing. In Ohio I can get the month of November, part of December, maybe a little January pending the year and some of late March. February/March seems to miserable that I have not been able to camp for other rotten weather reasons.

John

[JohnB]

Originally Posted by frank

Thanks for the pictures, John. I've been seriously considering enclosing and heating the two tanks on the 2363 to allow for cooler weather camping. Because of the way the tanks sit, I'm thinking of 1/4" ext grade ply boxes lined with foam..

That insulation looks interesting. Going by the example install shots and the estimated R values, it seems they are using the air pocket created by the foilbuild to gain R. The bigger the pocket created, the higher the R value. So the R15 doesn't seem too far fetched with a 4" frame channel when going by the manufacturers info there.

- Frank

Frank

Yes the Flex Foil does look interesting. The roll I get will also be used towards my sons house crawl space.

As far as heat, I really do not want to heat real hot, just keep it like 40 on a night that is 20 or 15. I'm thinking if it is too hot, 60 to 70, then condensation may/will come from it. Actually the water in the tanks are probably 40 or so. So they create a level of heat and when hot dish water/shower goes down the drain. If we can keep the drafts out the rest may take care of a lot of it.

I also thought your fresh tank was under the bed. Was it? If so then that tank is already inside.

John

[frank]

Originally Posted by JohnB

Frank

Yes the Flex Foil does look interesting. The roll I get will also be used towards my sons house crawl space.

As far as heat, I really do not want to heat real hot, just keep it like 40 on a night that is 20 or 15. I'm thinking if it is too hot, 60 to 70, then condensation may/will come from it. Actually the water in the tanks are probably 40 or so. So they create a level of heat and when hot dish water/shower goes down the drain. If we can keep the drafts out the rest may take care of a lot of it.

I also thought your fresh tank was under the bed. Was it? If so then that tank is already inside.

John

John,

40 sounds like a good figure and is right around what I had in mind for "heating".. I'm still deciding on what to use to generate the heat, but there's some Klixon thermostatic switches out there that have set points right around the 40 mark. I have to run a little test or two, but I suspect a section of heat tape inside the box may do the trick.

Like you said, just getting them directly out of the cold breeze may be more than enough to comfortably extend the season.

You are correct, fresh is under the bed. The grey & black tanks are mounted not quite side by side underneath. I think I can actually (and even rather simply) enclose the two tanks, drain pipes and the valves in one (maybe two) pieces. Obviously, I'll need a door for valve access

- Frank

[JohnB]

Originally Posted by frank

I'm still deciding on what to use to generate the heat, but there's some Klixon thermostatic switches out there that have set points right around the 40 mark. I have to run a little test or two, but I suspect a section of heat tape inside the box may do the trick.

Snip... Obviously, I'll need a door for valve access

- Frank

Frank

Yes the Klixon switch is about the most simplistic. Have to figure out what differential they have. At set point +- 2 or 3 degrees??

Depending on ones stash of left over stuff…A low temp thermostat running a relay. Have not yet sorted this one out yet as I can run the furnace and get heat form the ducts.

On heat tape, I “thought” they had 2 types. The one type it will melt the tape if it is not wrapped around a pipe with water to cool the tape. I had some of those years ago. The other type, they could be loft out in the open and not burn up. Have to read the packages.

Actually a 40 watt rough surface shop light bulb might be enough. Or a 60 or a 20 watt. You screw in or plug in the light blub thru your access door when you get to camp. And take out when traveling and bouncing down the road. You can also see what holes to the outside world exist at night….

This winter I will have temperature data off my sensor to help see what it is we really do have and will share with the group. I know others are up to this enclosed tanks topic too.

John

[frank]

Originally Posted by JohnB

Frank

Yes the Klixon switch is about the most simplistic. Have to figure out what differential they have. At set point +- 2 or 3 degrees??

Depending on ones stash of left over stuff…A low temp thermostat running a relay. Have not yet sorted this one out yet as I can run the furnace and get heat form the ducts.

On heat tape, I “thought” they had 2 types. The one type it will melt the tape if it is not wrapped around a pipe with water to cool the tape. I had some of those years ago. The other type, they could be loft out in the open and not burn up. Have to read the packages.

Actually a 40 watt rough surface shop light bulb might be enough. Or a 60 or a 20 watt. You screw in or plug in the light blub thru your access door when you get to camp. And take out when traveling and bouncing down the road. You can also see what holes to the outside world exist at night….

This winter I will have temperature data off my sensor to help see what it is we really do have and will share with the group. I know others are up to this enclosed tanks topic too.

John

Yes, this topic should generate some interest

I took a look at some of the Klixon type switches. The stuff that most places carry off the shelf have wide differentials (20F) and typically high set points. Common to use these for attic fans, etc so it makes sense. On "special order" you can have just about anything you desire, from below zero set points to single digit differentials. I bet the minimum order on those contains a lot of zeros, so your thermostat suggestion might be a more viable alternative.

Either way, I plan on including something for a high limit cut-out.

I believe you are correct with the different types of heat tape. I seem to remember using different types when wrapping some pipes vs. setting up a de-icer on someone's roof.

The light bulb is a workable option. I know some people strategically place them inside their trailers to prevent pipes from freezing up, and I've seen some high-school incubators heated quite nicely with light bulbs as well.

One thought I had was using a section of rope light - it's very low profile, easy to get, relatively inexpensive, runs usually around 6 watts per foot, can be cut to length to produce the desired wattage, and can be snaked around to spread the heat and eliminate hot spots. In quantity, this stuff can produce some serious heat - I saw a guy leave a 100' spool plugged in on a wooden floor for about a half hour - It did indeed char the floor and produce some smoke. Spread out, the heat is much more tame.. most packages I have seen of that stuff (and every roll) states to not plug it in when it's bunched up

Sorry for hijacking your thread!!

- Frank

[MACK C-85]

Another prospective......We ordered our trailer with the Heated Tanks option from the factory, we have two switches on the wall above the kitchen sink, one for the Potable Water tank, and one for the black and gray tanks. We have camped twice where the temp dropped into the low twenties/high teens overnight (35-40's daytime) without any issues. Of course you have to make sure you have water in all the tanks, but they seem to work (with admitted limited use) very well. None of our tanks are enclosed and I have often wondered if that would be a help or if it might overheat? The switches are currently on/off only, no temp control.

[Sunline Fan]

Originally Posted by MACK C-85

None of our tanks are enclosed and I have often wondered if that would be a help or if it might overheat?

Nothing like a big boiling tank of sewage under your floor!

Jon

[SanDimasJoe]

John,

Exactly what did you do to keep the dump tank release handle from unscrewing itself? My black tank dump tank handle unscrewed itself while on the road between New Mexico and Arizona. There was enough threads left on the end so that I could cut off the part that was ground down by the dragging on the asphalt. I could then screw the end back into the valve. I keep the handle secure with a flexible tie on the handle to the frame. But I would rather have something more secure.

Joe

[MACK C-85]

Nothing like a big boiling tank of sewage under your floor!

That definitely wouldn't be a good thing But.......

I'd be more worried about the blob of melted plastic that used to be my black (or gray or fresh water) tank laying under the trailer

I did a little research and most of the commerically available heater kits do have cutoffs....on 40 deg. off around 60 deg......so I guess cooking the tank isn't that great of an issue. I will have to look and see what brand SUNLINE used.

See the black tank dump handle about ready to completely unscrew it self.

Thanks John.......I also just discovered this problem on our last trip, it hadn't seperated yet, but it was close. I just screwed it back on the valve stem at the campground, but now I know I can crawl back under with an easy fix

[Sunline Fan]

I'm not sure if I have these extra long handles or not, but would loc-tite solve the problem? I've never checked them, so if I do have them, I should probably secure them now instead of when it's too late.

On a side note, one of our friends who have a Jayco FW found a problem with their black tank recently. The wife had gone up to use the coach with a friend and they leave the hose for the black tank flush hooked up all the time, with a tee off the auxilary spigot. She went to turn the sprinkler on (on the other side of the tee) and turned on the wrong valve. The black tank flush filled up the tank and started to come up through the toilet. One of them went to go to the bathroom and picked up the cover, only to discover it was about 30 seconds from over filling. As a result, like John said, it has really flimsy straps holding the tank up, and it bent those right now because the whole tank bowed. To make it even worse, this all happened inside the front basement! So they spent the early part of this past weekend visiting a welding shop to get some HD brackets and straps and then installing them until 2 A.M. I'll be ugly if the black tank flush is left on now!

Jon

[MACK C-85]

John B's method is probably the simplest fix, I'll summerize until he can respond (a picture would be worth.... .):

Unscrew the handle
Thread a properly sized nut onto the threaded control rod
Reattach the handle
Tighten the nut you added against the handle to "jam" it in place.

Both the Black and Grey rods are extended on our trailer and will get this fix after "Hanna" does her thing this weekend.