Single beam tongue problems. Propane tanks and mini split???

[mikeyk101]

>>> as there is some ventilation?

"SOME", is not the immediate answer, as you really need to replicate the ability to circulate the same CFM in and out as it would if it were outside. Now that seems easy enough if you just measure the sq inches of the openings the unit already has, right ? But you have to realize that would be "Free Air" CFM, and outside does not have to address any drag or restriction caused by added duct work.

So, the obvious answer to that is to leave enough headroom (slightly larger ductwork and or less bends) to provide for that. And, if you can not, you add additional forced air methods to move air thru the condensor. Some might not want to add additional current draw with even more fans, but you either size up the ductwork or deal with the extra draw.

Propane tanks show up INSIDE all over in these builds be it right or wrong. Yes, bad things can happen if they overheat like: venting, catching a lick of flame and blowing up. Blevies are cool on youtube but I would not want to be there!

But it's no different really than a leak in a line leading inside the trailer anyhow. People who put them inside a small box create a small vent above for air inlet and a vent below for the propane to escape (it goes/flows down naturally). By the way, why so much propane with diesel heat options ?

Venting the room is pretty easy. Yes, small scoop.evac vents work while underway, but when stopped, there can be all sorts of options. First though, the minisplit needs a dedicated, ducted in and out. I dont like venting forward because it is harder to keep rain out into a 60mph headwind. So, I'd vent heated air out the bottom, and inlet air via the sides thru stainless vents. Check the marine industry... lots of beautiful stainless vents made for just that.

Hey, you might just crack both doors for starters, but I've seen whole floors removed or open, which I would not advise.. I'd make doors that open and close under there... and by the way, that section that is walled off ? Do not keep the same height as your trailer floor. Remove the floor up there and make an aluminum pan that sits down on the frame (corrosion protection between obviously). That way any drips or leaks can get out thru designated duck drains before it can ever reach floor height.

Crap... gotta go to work.... I'll look later if I covered everything.....

Wow, that is a lot to digest but great info. So ventilation is key, I think I can manage that. Changing out the flooring shouldn't be too hard and being able to open a floor hatch is very doable. Again, something I didn't even think about.

Just thinking out loud but since heat rises, wouldn't it be better to vent the heat out of the ceiling? I could install a a 14x14 ceiling fan with a cover like one of these:
https://www.campingworld.com/camco-vent-cover-white-94931.html?cgid=vent-covers and I know these work well at keeping rain out. I added one on my toyhauler after going through a storm and not being able to open the vent for fresh air. And then have a decent sized hatch on floor for fresh supply but will need to cover the opening with some kind of screen to keep critters out.

As far as 20lb tank, its also more about readily available replacements if out somewhere and need a refill. They can be found at just about any gas station but maybe 20lbs is overkill. I wasn't planning on installing a furnace so one less thing. I would probably go with a 12v fridge so propane not needed there as well. I was considering an on demand water heater so that would require propane. I will probably just have a sink, not sure about shower but leaning against that right now but hot and cold running water in sink would be nice. I was thinking maybe a 2 burner cooktop but don't want an oven. I never use the one in the toyhauler I have now anyway. I do have outdoor grills that get used the most and an easy way to hook up to propane for that would be a plus. And lately, I've been using a propane fire pit so I wouldn't mind having a quick disconnect on a longer propane hose to use with that. Those are much easier than wood fires.

And Im just now learning about the diesel space heaters. I like what I see over propane heaters especially about the lack of condensation building up. I think I will have to look into those a little further. But also as far as heat, I'm seeing that many of the mini splits are actually heat pumps and provide both cooling and heating. Since I usually dont go camping in single digits or sub zero, do you think that the mini split might be sufficient?

I'm kind of glad that I am just planning the conversion now as I will have plenty of time before next spring to get it ready. It is a lot easier working out as many details as possible upfront instead of having to go back and make changes. Especially once holes are made and studs cut. Right now I'm just looking a blank canvas ready to be created with no need to rush.

[Grummy]

>>wouldn't it be better to vent the heat out of the ceiling?
Yes, but, in the case of the Mini Split, you really do not want it just running blowing hot air around in the room. You really want to duct cooler air in the intake and duct the hot air out somewhere it is not just sucking the hot air back in. So, it comes down to ductwork for that condenser.

It'd be no different for a window air unit when you bury it inside a cabinet. You have to provide cooler air to each SIDE of the part that usually sticks out the window, then separately sealed from that, ductwork on the section that goes straight out that is blowing the hot air. With either system, efficiency is depleted if you are sending the hot air right back into the cool air intake. So the better the separation, the better the efficiency. Obviously, a Min Split has a front and a back, of which cool air comes in one side and hot out the other as the cool air cools the coils inside.

>> I could install a a 14x14 ceiling fan with a cover like one of these:

Yes, you could.... I dont think I saw what your front roof section looks like. Some are tapered down towards the front in the V Section. But again, if you get a good duct system, you shouldn't be venting much heat. If I was using this new V Section as a mechanical room, I wouldn't want everything and anything in there getting heated. So if you need to vent, at that point, you are venting for other reasons, like the potential for a propane leak or perhaps battery gas if you use lead acid (Battery gas goes up and is kind of corrosive, Propane gas goes down - Lifepo doesnt gas at all, but you want to avoid heating it too much or freezing it).

>>> As far as 20lb tank, its also more about readily available replacements...
Indeed. I only use propane for hot water via one of the instant, under $150 units (I think I bought a Foruvee). LOVE that thing. It uses very little gas, and because it is the only thing I use Propane for, I have a 5lb cylinder. Yes, I have to have it filled, but 1) it lasts a long time (when I run out, I spin on an expensive 1lb'r until I get home) and 2), 1lb'rs cost over $6 now, and I think a 5lb refill was under $4 last time I filled.

Your comment on Moisture from Propane furnaces are when you use an internal combustion heater... I'd recommend against for the reasons you already know. Way, way too much water creation. But there are external combustion propane furnaces available. Not as efficient as these diesel units though.

I've had the expensive diesel heaters in the past in rigs (Espar, Eberspacher) and they gave me a few fits once in a while. You simply have to clean them once in a while if you have run them on low heat too much. My Eberspacher was undersized for the rig it was in and it did better because it ran on high a lot more. Now I run the Chinese heaters. At the $129 cost, you just can't beat them, and you can purchase like 6 of them for the cost of one German one.

They do have one issue though in comparison, and that is that the Chinese ones generally do not have a full functioning thermostat like the german ones. The German ones will idle up and down as necessary, even shutting completely down when temps have been reached and restarting when temps drop. Chinese units just have a range of heat from low to high..... if you buy one that is too big, you ROAST all the time. If you buy a smaller one, it can idle lower, and not cook you as easily.

>>> I would probably go with a 12v fridge

Some of these new ones are awesome. I've got two ICECO's and love them. I only have 400 watts on the roof and they run without worry.

>> I was considering an on demand water heater so that would require propane.... sink... shower

So, this too is where the separate mechanical room is great. Well, if you are going to do underframe tanks. For me, with underframe tanks (yes, not the ultimate for cold winter camping), you can put your entire water system in that mechanical room (water pump, Water heater, valving etc, then run your main line under the trailer, using T's to go up directly to the location of use. Doing this limits how much damage you get when you get a leak. The parts with the most "joints" ends up being in the mechanical room.. the one with the slightly lower floor area... the one where a puddle of water doesn't hurt much and can find it's way out easily.

>> maybe a 2 burner cooktop
I've had them in earlier rigs, but they burn precious counter space and frankly, dont like cooking inside anyhow. I used to drag around a typical dual burner coleman propane job, but it sits on the shelf in the garage now. I purchased two of those $20 Butane ones from Wally world and love them. Grab one, set it anywhere (though I bring a few door shims along to level them when necessary). Light, small, instant because there is nothing to setup or connect. Well, er, I do have those flipfold aluminum wind block things, but they store flat at least.

>>> I do have outdoor grills that get used the most and an easy way to hook up to propane for that would be a plus.... fire pit.

Well then you probably do need the 20lb'r and the QD's. No problem. You have a big enough trailer !

>>> I usually dont go camping in single digits or sub zero, do you think that the mini split might be sufficient?

Probably. If you do the mini, I wouldn't invest in any other furnace until you find out if it's enough.

>>> I'm kind of glad that I am just planning the conversion now as I will have plenty of time before next spring to get it ready.

I wish I was doing another. Half the fun is the rough drawings, then moving to CAD to really see how things will fit.
Proper balance is a good deal of guess work, like predicting exactly how things change when you have a full verses Empty water or waste tank. I have a water tank, but I only have a grey waste tank. No black. I've used the 5gal Thetford curve porta units and have been very happy doing so.

Another tip is to keep a self tallying spreadsheet of every item you install regards WEIGHT. It adds up fast. With additional columns, you can divy up the weight of things as they exist or cross over into different sections of the trailer, giving you a rough total of each corner of the trailer. I've been lucky enough to live near a facility that has TWO scales right next to each other and have been able to get my actual weights from every aspect, right to left without tongue, right to left with tongue shared across the two scales. Total Axle with and without tongue. It's pretty cool to see how it all pans out !

Keep this group posted on your progress. It needs more good conversion discussion !

[mikeyk101]

More great info. Thank you, thank you, thank you!!!

Just to reply to your last post about heat, I was mentioning condensation as a result of a stand alone propane heater like a Little Buddy since I am not planning on a furnace anyway. And a Little Buddy style was not what I wanted either because of this. If the mini split ends up being able to provide enough heat, I have killed 2 birds with one stone, heat and AC.

My roof is flat from back to front to the point of the V and is a one piece roof with those radiused panels surrounding the edge. So a ventilation fan wouldn't be too hard but after what you mention, I will investigate further and try to figure out what the best way forward will be. It seems like I have multiple options.

And what you say about a countertop stove makes sense too. I think I will nix that idea. Like I mentioned, a lot of cooking gets done outside anyway so that will just have to be the way it's done which I really don't mind. I do think I would like to have a microwave though. My toyhauler microwave sees way more use that the stovetop too. That and a coffee maker...So as far as countertop, my plans are to just have a sink and space to put stuff.

I have been going back and forth about mounting tanks under the frame. I know it's a possibility but I would still have to take cold temperatures into consideration. Years ago I had a travel trailer at a campground in Indiana. It was an old Fleetwood. It had the freshwater tank mounted inside under a fold up couch. I kind of like the idea of an interior fresh water tank as that could extend my camping season. I know there are heater pads that can be put in underside of these tanks to keep them warm but they require power to work which would reduce my electrical capacity unless on shore power. So a small fresh water tank hooked up to a pump to provide water to the sink could be ideal. The sink would be the only thing that uses water since I plan on using a standalone portapotty for when nature calls. So a blank tank will also not be needed. That would leave only a grey tank for the sink discharge. A possibility to handle that might be to figure out a way of fitting in one of those portable waste tanks under the sink. That could be the best and easiest because than I wouldn't have to move the trailer to empty it. So no need for tank sensors or a panel to monitor it.

And yes, weight distribution is something to keep an eye on. Id like to occasionally use this on trips without the trike. So if I put too much stuff forward, without the trike, the tongue will be overloaded. I will see what I can do to balance things out to get a happy medium. As far as scales, I'm lucky because I have 2 truck stops within about 10 miles away that have the CAT scales and with the app, it's very simple to do it. Unfortunately they won't do side to side weight or weight on individual tires. And I also have a Sherline tongue weight scale that I bought just after getting my toyhauler. It will measure up to 2000lbs which should come in handy too.

With all this good information upfront, I feel like I'm ahead of the game now. A couple weeks ago, I only had a vague idea that I wanted to do a CTC and now I have an actual path forward to make it work.

[Grummy]

>>> a Little Buddy

Ya, if your in the cold with only that, one might not realize just how much water your adding to a room, even with windows open. And of course adding the water... well, mold in the corners of everything is just awful.

>> I do think I would like to have a microwave though.

I went that route too... it's just a handy thing to have. I have done just the sink too, and built a fitted cutting board for the hole. One of your two birds scenarios. To keep from going in and out to use a sink, I found that just having a nice collapsible sink for outside is a must. To get the water there, I took a regular old sink sprayer, changed the hose out to a 3/8" ID really flexible tube. In both the front and rear of the trailer, I have a hot water port I can plug into to either fill the collapsible or just spray things off. Rather than set the hot water heater to blazing hot, I just keep it at perfect hot so it works for just about any need.

The above is just an example of how I changed what I thought I NEEDED in a rig. I once had everything.... now I realize that less really is more.

>> tanks under the frame. ..... cold temperatures...

You will have to figure out what fits your style in this regard. I love to winter camp, but the reality is I have less time to actually do it than I think I do. I went with under tanks with the same thought that I could heat them. But then I realized in my case, if I want to winter camp, I just simply apply the twin 5 gallon jug concept under the sink and not use the under tanks. Best of both worlds. It's also why I stick with the 5 gal porta potti rather than a black tank. BUT, only you can figure out what is best for your type of trailer living. And, you have a lot more space than I have... I only have a 6x12 ! So I have to compromise perhaps where you do not.

>>> I wouldn't have to move the trailer to empty it.

Dont forget the option to drag along one of those blue tank buggies.. you can empty into that and haul it away without moving. Just another thing that might end up in that "Mechanical Room". Lol !

>> Without the trike, the tongue will be overloaded.
I've dealt with similar. I just want to haul a 300lb scooter... on occasion. I did a front bed so I do not have to unload anything to sleep when enroute. I essentially put every fixed item on the drivers side wall, then compensate with things under the right side like the fresh water tank and a flush in the floor tool storage area. Above the floor on the right, I have a removable frame work that holds my larger ICECO fridge, Ice maker and moveable soft tubs. All these items when in place and loaded counterbalance the left side within 30lbs and the trailer rides level side to side.

When I haul the scoot, that framework comes out and the fridge and tubs get relocated forward or in the two vehicle. Indeed, it DOES take some forethought when you have a come and go loading scenario, or you have some real issues that are harder to solve later.

>>> I will see what I can do to balance things out to get a happy medium.
With the trike, your goal might be to locate that trike as on top of the axles as possible when loaded so that nothing really changes when unloaded except overall weight. You'll have to get creative with flexible, relocatable or collapsible furnishings behind the trike area when you have to haul it. In a worst case scenario, a rear fresh tank... actually whatever placement works best, can always be "adjusted" for targeting tongue weight when enroute and filled when you get onsite.

Post your progress !


With all this good information upfront, I feel like I'm ahead of the game now. A couple weeks ago, I only had a vague idea that I wanted to do a CTC and now I have an actual path forward to make it work.

[featherliteCT1]

Grummy has provided great advice.

Here is my 2 cents:

I installed a Walmart window air conditioner in my 7x16 V Nose trailer. I have experimented with 5k btu, 6k btu and and 8k btu units. I settled on the 6k unit due to the maximum amp draws that my 12v DC electrical system can handle.

Taking into account inverter inefficiencies, the 5k, 6k, and 8k units draw approximately, 35A, 40A, and 53A, respectively, when the compressor is on, but about 4 times those amps at start up. These are actual numbers measured in use.

With my 1,400 watts of solar panels (14 x 100 watt panels) mounted on my roof, flat, in decent sun, I can barely keep up with the amp draw of the 6k unit.

My 1000 watt inverter would not consistently start the 8k unit. So, I use the 6k unit which starts up without issue.

I have researched mini split air conditioners and believe the smallest one that runs on 120V AC current is about 9k btu and draws about 58 DC amps when the compressor is on. As a rule of thumb, inverters are only 85% efficient which means 15% more amp draw than what is posted on the sticker of the air conditioner. I have no idea what the start up amp draws are for the mini splits. There may be some mini splits that do not have inductive motors and thus do not have the huge start up draws. In any event, the solar powered electrical system to run one of those mini splits would have to generate significantly more watts than my system can handle or produce. I do not have enough roof space for more panels.

The BMS for my 280A Lifepo4 battery can only handle 120A continuous, which means any 120V inverter run off of that BMS can be no more than 1500 watts.

I run a 1000 watt inverter because:

(i) I already had one 1000 watt inverter plus a spare and did not want to buy two new 1500 watt inverters to replace them,
(ii) a 1500 watt inverter is physically larger and I did not want to rewire my entire electrical system to make room for the 1500 watt inverter, and
(iii) my solar system would have to be massively enlarged.

Finally, I am concerned about vibrations breaking my air conditioner. My $180 Walmart window air conditioner is available at almost any Walmart and can be fairly easily replaced when it eventually/inevitably fails.

[mikeyk101]

Grummy has provided great advice.

Here is my 2 cents:

I installed a Walmart window air conditioner in my 7x16 V Nose trailer. I have experimented with 5k btu, 6k btu and and 8k btu units. I settled on the 6k unit due to the maximum amp draws that my 12v DC electrical system can handle.

Taking into account inverter inefficiencies, the 5k, 6k, and 8k units draw approximately, 35A, 40A, and 53A, respectively, when the compressor is on, but about 4 times those amps at start up. These are actual numbers measured in use.

With my 1,400 watts of solar panels (14 x 100 watt panels) mounted on my roof, flat, in decent sun, I can barely keep up with the amp draw of the 6k unit.

My 1000 watt inverter would not consistently start the 8k unit. So, I use the 6k unit which starts up without issue.

I have researched mini split air conditioners and believe the smallest one that runs on 120V AC current is about 9k btu and draws about 58 DC amps when the compressor is on. As a rule of thumb, inverters are only 85% efficient which means 15% more amp draw than what is posted on the sticker of the air conditioner. I have no idea what the start up amp draws are for the mini splits. There may be some mini splits that do not have inductive motors and thus do not have the huge start up draws. In any event, the solar powered electrical system to run one of those mini splits would have to generate significantly more watts than my system can handle or produce. I do not have enough roof space for more panels.

The BMS for my 280A Lifepo4 battery can only handle 120A continuous, which means any 120V inverter run off of that BMS can be no more than 1500 watts.

I run a 1000 watt inverter because:

(i) I already had one 1000 watt inverter plus a spare and did not want to buy two new 1500 watt inverters to replace them,
(ii) a 1500 watt inverter is physically larger and I did not want to rewire my entire electrical system to make room for the 1500 watt inverter, and
(iii) my solar system would have to be massively enlarged.

Finally, I am concerned about vibrations breaking my air conditioner. My $180 Walmart window air conditioner is available at almost any Walmart and can be fairly easily replaced when it eventually/inevitably fails.

From the research I have found, it seems like you are way off on the amp draw for mini splits. I don't doubt what you say as far as window AC units but it looks like mini splits draw far less than those. Take a look at just one web site I found.

https://learnmetrics.com/how-many-amps-does-a-mini-split-use/

Looking at this, I could easily get away with a 9000btu or even a 12000btu setup without depleting the batteries too quickly. And this is only one of a number of sites that confirm similar results.

[featherliteCT1]

Are all those amp draws based on 220 volts?

[mikeyk101]

Are all those amp draws based on 220 volts?

I'm not sure now. I will look

[mikeyk101]

Ok, I found this page that specifically gives amp draws in various voltage. Here is what I found for 115v

https://airconditionerlab.com/how-many-amps-does-a-mini-split-use/

[Grummy]

Those amp draws stumped me at first too, but I think he's right. I think my 5000btu window shaker (which is plenty for my 6 x 12) pulls just under 40 amps FROM THE BATTERY when running. It's like 400 watts on 120v, but with the 12v math involved, it is near 40a,

I only have 200ah of battery and 400watts of permanently installed panels. I can hold my own if I plug in 200 more watts in good sun, but it is not something I bother doing. If I know I need the genset along, I take it and it just idles along quietly.

[mikeyk101]

I have no doubt featherliteCT1 is correct for regular window AC units but he is basically saying that there is a bigger draw when using a mini split than those Window AC units

I have researched mini split air conditioners and believe the smallest one that runs on 120V AC current is about 9k btu and draws about 58 DC amps when the compressor is on. As a rule of thumb, inverters are only 85% efficient which means 15% more amp draw than what is posted on the sticker of the air conditioner. I have no idea what the start up amp draws are for the mini splits. There may be some mini splits that do not have inductive motors and thus do not have the huge start up draws. In any event, the solar powered electrical system to run one of those mini splits would have to generate significantly more watts than my system can handle or produce. I do not have enough roof space for more panels.

Everything I am finding shows just the opposite and that mini splits are much more efficient and use significantly less amps than a standard window AC. Maybe I'm missing something?

[Grummy]

I think the mini split comes around as more "efficient" because of its ability to ramp up and down.. dialing in to need, rather than just running at one or two "speeds" ? I see them listed with amp draw ranges.

If you think about a window air, they have one motor that drives both the evaporator and condenser fans, whereas the Mini has two completely separate units, meaning each side has to have it's own fan motor.

I lean towards featherlites comments for replace-ability issues, Surely one dies on you when your anywhere on the road and you might be able to plop a brand new window air in its place rather than track down someone who can service the mini. Not only that, you now buy those "extra warranties" and get replacements free or really cheap.

On the other hand though, I think the mini split is easier for the average guy to install because the two halves are completely separate. With the window air unit, to "build it in" and really do so without compromising its full capability, you do have to isolate the front and backside as if it is in a window like it was intended to be used without inserting any restriction to its original "free Air" CFM. I have seen quite a few people complain that the unit does not cool like they thought it should, but when you see pictures of their install you can see that the backside is not able to bring in cool air and exhaust the hot air without the two being intermixed, or restricted.

I'm not against the minsplits at all, I just don't like the look of them tossed up there on the tongue of a otherwise great looking trailer. I've seen some where they mount them on the back when they do not have a ramp door, or have just an entry door off to one side,.. I've seen them on the roof of some, and one I recall in a large front tongue box with no floor in it at all.

[Gulfcoast]

I love to see a mini split unit on the tongue of a trailer. They have maximum cooling without any restrictions.

[halbraun]

I love to see a mini split unit on the tongue of a trailer. They have maximum cooling without any restrictions.

I worked for Trane a long time.. I would never suggest putting the outdoor unit “indoors”. Even on the tongue it requires a couple of inches clearance. Plus, while MUCH quieter than other units (rooftop or window) it would transmit more noise inside rather than outside an insulated trailer.

I agree with Gulfcoast.. With the right heat pump mini split, you get great efficient cooling, and adequate heat (down to 34 or so) at minimal draw. My 12500 btu draws about 8 amps at 120 for both the compressor and air handling unit. I have hauled it well over 10,000 miles without a hitch. I live in FL so I don’t worry about the heating so much, but it kept me comfy in CO down in the thirties..

Easy to mount on unistrut on the front, it’s a mount and forget item.. PS.. make sure your jack handle has room to go 360 degrees!

viewtopic.php?f=42&t=73773

[featherliteCT1]

... featherliteCT1 is ... basically saying that there is a bigger draw when using a mini split than those Window AC units

To clarify, I was not saying that a mini split is less efficient than a window AC. I was just trying to point out that I think you were underestimating the number of amps that are required to run an air conditioner, mini or window, when drawing from a 12v battery utilizing an inverter.

Please keep us updated concerning your planned electrical system.