Power/holding tanks/solar???

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SouthernStyle

Member
Joined
Aug 16, 2019
Posts
6
Location
Louisiana, at the moment..
I am so new and over my head here. Any help is greatly appreciated!
I recently purchased a 1979 serro scotty sportsman. It is 12ft with the indoor shower combo. Everything original and working.
      I removed the propane stove after it flamed up 2 ft when I lit it. The dometic fridge and roof AC/heat work great..if its plugged in. There is no battery anywhere.
      So, IF I were to go with solar how many, what size, or how long would that last?
What about a solar generator? I have a 1500 watt inverter I just do not know the best off grid power source to set up IN CASE I am somewhere unable to plug in.
        Guess I will hit ya'll with my next question while I'm here..
This camper has only one holding tank. Fresh water, heavy iron that is probably the original one. I am replacing it with fresh and grey tanks but what gallon size would you recommend..
I will be the only "traveler"..
        I live in a tiny rural place and am doing this work myself and any advice is welcome!
Tell me what to do and I can do it but trying to figure out which works best with so many choices and I'm lost!
Thank you so much!
(Be prepared because I definitely have more questions?)
 
I kind of hate to tell you this, but your Scotty doesn't have enough roof for solar to do very much good. 
Why you have in inverter and no battery is a mystery.  I would guess that the PO took it out and never replaced it.  The battery is also required for the Break-Away function of the unit's electric brakes.  That is the little cable that you attach to the hitch is for that.
The Dometic reefer may also require 12VDC if it is a newer (less than 30yo) unit.  If it works right on shore power then it is OK without it. 
Most RVs that period had only a potable tank, a small gray tank and black tank.  The heavy potable tank was so it could be pressurized to make running water.
As to what size tanks?  All you can fit.
I will suggest that if you still have the propane stove, you get it repaired if you ever want to have anything warm to eat. 
Memories (Old) are working here.  Was the stove really propane or was it a Coleman sort that ran on liquid fuel?  If it was that, get it back and learn to use it right.
As to what to do for power when dry camping or boondocking, a small generator might be your best bet, but there is probably nothing that you can lift and carry that will start and run the roof A/C unit.
Nobody can tell you what will work best until you tell us how and where you expect to use the unit. 
Good Luck
Matt
 
An excessively large stove flame usually means the regulator at the tank has failed and there's too much pressure in the propane system.  It's supposed to reduce the tank pressure of 100-150 PSI to around 0.5 PSI to send on to your gas appliances.

Replacing the regulator is simple and inexpensive.  Just make sure you get a two stage regulator designed for an RV, not a single stage one used in portable stoves and grills.

Here's one example - notice it has two stages in series.  A single stage regulator lacks the smaller first stage, if that is what you have on your trailer it's the wrong one.

https://www.etrailer.com/Propane/Camco/CAM59323.html

Others are available for different mounting positions, with preselectors that automatically  switch between two tanks, etc.

Like Matt said, the heavy, metal fresh water tank uses compressed air to provide water pressure.  You'll have to add a 12 volt water pump if you replace it with a modern plastic unpressurized tank.
 
What about a solar generator? I have a 1500 watt inverter I just do not know the best off grid power source to set up IN CASE I am somewhere unable to plug in.
A solar "generator" is an inverter + battery+ solar panel. Think of the solar panel as the battery charger and the system becomes simple to understand. The inverter runs off the battery, depleting its stored energy. The solar panel puts energy back in the battery.  Like your bank account, you can't take more energy out of the battery(s) than you put in.

To actually get 1500 watts worth of energy from batteries would require more space and weight than you could possible have in a 12 ft Scotty.  As a practical matter, once you install one or two medium-size batteries, you can use the inverter to charge a phone, run a computer and maybe watch some tv.  The batteries also provide some 12v power for lighting, fridge circuit board, a water pump, etc.

The heavy water tank implies the pressurized water system that Matt described, but that seems hard to believe in a 1979 model. Pressurized water system in RVs went out of style a decade before that. I would have thought a 1979 would have a non-pressurized system.

Your trailer should have a single battery and a small (20A) converter-charger that produces 12 when plugged in and also re-charges the battery.


I'm not sure what year this is, but there is a Sero Scotty owner manual online at http://www.nationalserroscotty.org/img/manuals/2008HiLanderManual.pdf
And a brochure, circa 1970:  https://serroscottytrailers.com/Serro-Scotty-Brochure.pdf
 
The inverter is new and was gifted to me. It did not come in the camper. I think I knew that solar was just a wish because of the roof room. So, I should get a couple of batteries to power the inverter that will then power a light, fridge, phone and maybe TV? What size batteries? Do I plug my camper plug straight into the inverter?
    I have two 15 amp breakers. One operates the fridge, lights, plugs. The other operates the roof AC/heat unit. If I put the camper plug straight into the inverter to operate the fridge etc, should I flip the AC breaker off?
    Mercy! I am learning about things I never really wanted to learn...like algebra..?
    At least now I know that solar is not gonna work so I can strike that confusion off my list..thank you for that advice.
I may never stay anywhere that I can't plug in, but I would like to have some kind of back up power source just in case.
      The propane issue was from flames shooting up before I even turned the knob on the stove. Made my heart stutter..?
      I only have one small sink and the shower so I'm looking into the small electric tankless water heater unit for each. Good idea? Bad idea?
      I'm good with a small microwave and double electric hotplate for any cooking..plus my little grill.
      I have room for a 40/30 gallon fresh and grey water unit I just didn't know if that was overkill.
      I have never camped or "lived" in any camper aside from trips in my 20's in my parents motor home so I really am clueless..
Clueless but determined.
      Sorry for all the useless extra info..
 
SouthernStyle said:
So, I should get a couple of batteries to power the inverter that will then power a light, fridge, phone and maybe TV? What size batteries?
  What brand/model inverter is it?  That will dictate whether it's up to the task of charging and maintaining your house batteries.  What size and number of batteries did it originally come with?
If I put the camper plug straight into the inverter to operate the fridge etc, should I flip the AC breaker off?
Assuming this unit has a propane refrigerator, it and pretty much everything else in the camper should operate directly off of 12V.  No inverter necessary, with the exception of maybe the TV set.  The 120V breaker likely fed a charger unit that powered the 12V devices.
  Mercy! I am learning about things I never really wanted to learn...like algebra..
An EE degree is a good start...
  I only have one small sink and the shower so I'm looking into the small electric tankless water heater
Heating water is probably your biggest challenge.  I don't see anywhere this thing came with a water heater.  Heating water electrically works fine but you won't be able to do that off of a battery (just like you can't practically run A/C).
I'm good with a small microwave and double electric hotplate for any cooking..plus my little grill.
Microwaves and hotplates are also non-starters on battery.  On generator this is fine, as would be a coffeemaker.  Otherwise, I'd be looking at replacing or upgrading your propane stove with one that has an oven.  In my RV I call it the easy bake oven because it's so small and cute but it really does a fine job both warming up and cooking small meals.  Part of the schtick of camping is to not be in a hurry and while my RV has a microwave, the stovetop and easy bake oven gets way more use.  Just so much nicer to not have to fire up a generator to warm up a bowl of stew or heat up leftovers or whatever.  Just plan ahead a bit to give them time to warm up/cook on the stove in peaceful quiet.

If you resign yourself you will always have shore power or a generator running then some of the logistics of what you want to do become simpler.  There's a reason that even contemporary motor homes and campers come with propane appliances and that is simply it's a lot more difficult and expensive to try and run things off of batteries, "free" solar notwithstanding.  Having some amount of battery storage is a good idea but be cognizant of what you need to use vs like to use.  Fitting LED bulb replacements, using a vent fan instead of closing things up and running A/C, and being aware of what's drawing power and when are all steps we take to making a limited power source work.  Any watt not used is a watt that doesn't need to be generated or stored.  While you may think you'll always be on shore power, if you design for that you can probably bet there will be times you'll be sitting in a cold, dark camper.  Probably not realistic to think you'll turn this into a luxury motor coach either but you'll definitely want to design to some degree of autonomy.

If someone hasn't offered these already, here's a start towards your EE degree:

http://www.marxrv.com/12volt/12volt.htm
http://www.marxrv.com/12volt/12volta.htm

Mark B.
Albuquerque, NM
 
The inverter is a "PowerDrive" 1500 watt that my son bought when he went over the road driving. He gave it to me after he went into a truck that had a built in inverter. It does have a propane/electric fridge that I know works when plugged in but I'm not certain on propane. I snatched that tank off the camper before you could blink when the stove acted possessed. Probably a mistake in hindsight but I was so sure anything else would be easier and safer. Now..I see I may have screwed up
    There is a water heater in the camper that has outside access and a pilot you have to light. I haven't checked it either.
    12V and 120V breakers and batteries...you may as well be speaking ancient Chinese.
Sadly my life has always been "plug that in"... "flip that switch" or "turn it on" and VOILA I it worked. Now I have to get a "E E DEGRREEE"!
    So, if assuming everything works on propane does that mean the AC also? Lights?
Because even when the tank was there I only had lights if I was plugged in. There was not a battery in the camper when I got it so I have no clue what size, kind or where it even goes.
    I don't want to always have to be plugged in. I just need to know what my options are.
Should my hashtag be #StupidIsAsStupidDoes? thank you for the links!
 
A couple of points here, first off traditional deep cycle lead acid batteries have a limit on how fast they can discharge their stored power, the bigger the battery bank the faster its maximum rate of discharge with minimal voltage drop will be.  In order to run your 1,500 watt inverter at full output, such as when powering a microwave over, or other high draw appliance, you will need at a minimum a pair of group 27 deep cycle 12V batteries wired in parallel or a pair of 6 volt  GC1 golf cart batteries wired in series to output 12Volts DC.  This has nothing to do with how long the batteries will carry the load, just that when fully charged that they can provide 1,500 watts of output continuously  without excessive voltage drop which would cause the inverter to cut out, assuming appropriate (large) size wires are ran between the inverter and the batteries.

The capacity of the battery bank is a second concern, we have established that you need at least 2 deep cycle batteries to power your inverter at full output, (2 group 27's, or 2 6V GC1's) are actually marginal for this).  A good brand name group 27 battery holds about 100 amp hours of electricity, it is a good rule of thumb to never discharge them more than half way so as to maximize service live, so for a practical consideration, this means 2 X 100 AH group 27 deep cycle batteries discharged to 50% gives you 100 AH of electricity to use before needing to recharge.  1 amp hour is going to be about equal to running a 12 watt load for 1 hour, is about how much power a typical modern LED household "75 watt replacement" light bulb consumes.  Running through an inverter will result in some efficiency losses, which we will ignore for now as most modern inverters are around 90% efficient, at least at heavier loads.  By contrast a small "dorm room" type 500 watt microwave oven will draw about 950 watts of electricity while running.  Or about 100 amps DC from the battery, at this rate running your microwave for 1 hour would completely discharge your battery down to its 50% safe discharge limit.  (for those lurking yes I know this is a simplification).  Of course people rarely run microwave ovens for more than 3-6 minutes at a time, so cooking some frozen entree in the microwave for 6 minutes would in reality only consume about 10% of your available battery capacity.

You can see from this that you have to account for both how much power you are using in your appliance (watts, and how long your are using it)

1 modern LED household light bulb, you can run for about 100 hours on a pair of group 27 batteries, or you can run a small microwave over for about 1 hour total,  Typical modern flat panel TV's under about 42 inches in size consume between 20 - 45 watts of power depending on size, if they are "smart" how loud the volume is turned up, etc.  Other loads like the water pump are going to be trivial as you will run out of water tank capacity long before they amount to more than 10% of your battery capacity.  Your furnace blower is likely to one of the bigger draws, but again will depend on run time, how many minutes out of each hour your furnace blower fun needs to run.

As to the solar side of things more is better, though as little as 100-150 watts of solar panels can make a difference in extending your dry camping run time.  If possible though I tend to say 300-400 watts is the smallest solar panel setup someone should ever consider, of course the question in your case is do you have enough roof top real estate for 300-400 watts of solar.

P.S. Keep in mind solar panels only work when the sun is up, and work best when pointed directly at the sun, flat mounted solar panels on an RV roof, in full sunlight can be expected to produce about 5 hours of peak equivalent output per day, in average mid America conditions, so a 100 watt solar panel will output about 500 watts of power per day.  (in other words about enough power to run that microwave over for 30 minutes) or enough to half way charge your battery bank, if nothing is being ran at the same time to deplete it, this assumes no clouds, etc. so not exactly real world.
 
Thank you Isaac. I think I have crossed off the solar idea. I may have to revisit the propane but I still don't know if my AC/heat unit in the roof runs on propane as an option. I don't see anything on it to indicate it does. 
      Is there a place or person I could call and have a conversation with about all this? Someone who would say "get this and this and that and hook that one there and do it like this"..lol This figuring it out when I do not understand some of it is like trying to get out of a room that has no door. I just don't know how to apply what I'm being told.
I do thank everyone for the ideas and tools to help me along in getting this EE Degree..?
 
I don't know of any good place to call, though asking questions on forums like this is a good place to start.  Also there are a number of helpful (and some not so helpful) youtube videos on all aspects of RV life.

As to what runs on Propane, I can tell you certainly that your air conditioner does not run on propane.

In a typical RV you will have a propane powered water heater, as well as a propane powered furnace, and likely a dual operating absorption refrigerator that will run on propane, or AC power when connected to shore power.  Most modern versions of all the the above appliances also require some DC power from the onboard deep cycle battery to operate their control electronics, though there are few exceptions.
 
Southern,

It is clear at this point that what you really need is a native guide, a mentor or something like. 

You will not be the first single lady on the road, but it is clear that you are at the bottom of a steep learning curve.  It is steep, so some help can make a big gain for you at this point. 

A lot of us here were born knowing all this stuff.  (Yeah, RIGHT!!)
We all had to climb this mountain to get where we wanted to be.  Some of us had help and some of us made lots of expensive mistakes. 

Do you have a friend, acquaintance or family member that has been at RVing for a while? 
If yes, get with them.
If no, time to make a new friend.  Look around your neighborhood.  Is there an RV that comes and goes a lot?  You should (as I suggested before) get hooked up with Tin Can Tourists <tincantourists.com> and try to get to a local event.  Take pictures of the Scotty with you.       

I don't often suggest FaceBook because the censorship there is just appalling.  But it can be useful.  You have to be careful as some suggest that they have knowledge and experience that they do not.  There is at least one group for ladies on the road.

Matt
 
SouthernStyle said:
The inverter is a "PowerDrive" 1500 watt
You could probably use that for some things but it's really not the kind of inverter you find in most RV's.  It doesn't have an integrated charger, any controls or metering, and some devices may not be compatible with the kind of output it has.  So I'd hold that in reserve until you know for sure just what your final system will end up looking like and if it's a fit.
It does have a propane/electric fridge that I know works when plugged in but I'm not certain on propane.
Even if it doesn't, it's likely repairable knowing the cooling unit is OK.
There is a water heater in the camper
Oh, nice.  That makes things easier.  Even if it's busted the facilities are there to support one.
Now I have to get a "E E DEGRREEE"!
Don't worry, it gets better.  You get to be a load master, work through chassis dynamics, power generation/load management, HVAC, plumbing, wood and metal fabricator, and CFO all at once.  Just the EE part is a walk in the park.
There was not a battery in the camper when I got it so I have no clue what size, kind or where it even goes.
The intertubes are your friend.  Get on the google and see what you can dig up about this model. There's enough similarities between models and brands of trailers that you'll figure things out in short order.  My first pass at the battery location is to follow the wires, and look for where the battery tray or box is/was.  There's nothing terribly complicated electrically (EE hat on) about a small trailer like that, so the answers will present themselves with nominal investigation.  The way I approach an unknown as you have is to assume that everything works and is as built until a symptom or problem shows otherwise.  So base it on faith that most if not all of the systems are OK and you won't have to mess with them until you uncover a problem.  Odds are excellent you won't have to repair or replace every single thing in the trailer, hopefully just a few simple things to get it to a point where you can start using it.
I don't want to always have to be plugged in. I just need to know what my options are.
No, you don't but the good news is folks figured all this out in 1979 and well before, so I think it's more a case of you understanding what the capabilities are and fitting your uses within those.  I'm guessing you haven't done a lot of tent camping because most of that translates directly to basic trailer living (without the hassles of a tent).
Is there a place or person I could call and have a conversation with about all this?
You're not going to find a step by step instructions because what you're doing is unique to you and your goals.  Subsections of your project are likely well published but first you need to divide your project into those component parts.

Part of your education as an EE and now project manager is to identify what needs to be done, then the materials, resources and process that will realize it.  This may be as direct as identifying a widget that needs to be installed, and hiring someone to do it for you.  Or it could be a highly detailed and complex project of engineering, fabrication and integration (a teardown and buildup).  A journey of a 1000 miles begins with the first step and depending on what your goals are this might not be that bad, and the journey may take you in directions you didn't expect that can be fun and interesting.  By working with a basic trailer like this you will learn about things you never thought you'd have to but you will also gain the advantage of being self supporting with your equipment.  There's a confidence and Independence that results from not having to depend on others to deal with every issue you'll encounter with a camper. 

I've built, repaired, rebuilt and restored a number of things in my life.  From my perspective here as a third party observer is before I got too financially and emotionally involved with this camper is to see and make sure, by laying eyes and hands on every square inch, what I have to work with.  Is the chassis sound and is the structure intact?  This thing has been around the block since 1979 and no telling what it has seen and what has happened to it.  Even if it sat in a nice garage for most of it's life there can still be issues with water damage, insects, rodents and general decomposition and decay.  Wood rots, steel rusts, plastics get brittle and crack, seals and sealants dry out and don't seal.  Just a tiny leak in the roof or a bad window seal can cause a lot of damage once water seeps in.  Repacking wheel bearings, new tires, checking trailer lighting and inspecting the frame for corrosion, bends and breaks would be on the list.

Part of completing a large and complex project is defining the finish line.  What does this thing need to do and what should it look like when it's done?  From there you create sub tasks of repairs, replacements, additions and subtractions.  Again, it's perfectly OK to just identify things you like and making them someone else's job but you as the project manager have to be able to describe what the end result should be like.  There's a budget aspect too, it's nice to think you can push tasks onto others but it's not free, and you have to weigh the convenience and cost against the value to you.  Old stuff like this has little inherent value so figure most of what you spend will be lost when you sell.  So keep that in mind as you think of new things you'd like to do to it.

Again, from my casual observer perspective here you would be doing pretty well at your experience level to just functionally restore what's there.  Put in a working stove/oven, install a battery and get everything working again as it was in 1979.  Make sure it's roadworthy, and weather tight.  Then use the thing.  Nothing like a bit of real-world travels to reveal what you like about it and what you'd change if you could.  You might find that what it already has is adequate and no need to replace, or you could hate everything about it and sell it on craigslist after two trips.  But before I got all starry eyed about turning it into a palace on wheels I'd want to be comfortable with what's there and then figure out what can realistically and practically be done with and to a 40 year old trailer. 

Mark B.
Albuquerque, NM
 
SouthernStyle said:
Is there a place or person I could call and have a conversation with about all this? Someone who would say "get this and this and that and hook that one there and do it like this"..lol This figuring it out when I do not understand some of it is like trying to get out of a room that has no door. I just don't know how to apply what I'm being told.
I do thank everyone for the ideas and tools to help me along in getting this EE Degree..?

Right here on the Forum is a good place to start.  Break the projects down into individual tasks and post a question asking about it.  A seperate Topic (message) for each task is best to keep the replies seperated and uncomplicated.

Don't get overwhelmed trying to fix everything at once!

 

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