Seeking your input on a new project.

[Midwilshire]

Will be a difficult build as you have laid out. But that is what makes this hobby great! Go for it. Thinking outside the box is what it is all about...Do some research on your hvac. Suggest minni split  inverter technology. Probably two 9000 BTU heat and cool would serve you well from the teens to 100F.  Would only pull a max of 13 amps. where two roof tops or window ac would pull up to 40 amps on start up.  Also look into induction cook tops. Much more efficient than drop in ranges. Toaster ovens or the induction dutch ovens can supply oven needs. Saves space and dollars. Eliminate LP  from the coach. Led lighting is inexpensive also.  Good luck    Bob

Bob, Gigi and I checked out your build pictures.  Wow.  You're in a whole different league!  We got some great ideas from your pics.  But I fear we'll still look like a rag-tag gypsy wagon parked next to one of your rigs.  (This is not meant to disparage gypsies.)

We're looking into mini-splits now.  I agree with your suggestion of two 9000 btu units.  Any recommendations as to brand / supplier / install "gotcha's?"

[Eric]

24 volt lighting is easy to get as you can still used most 12 volt fixtures... As far as your alt is concerned you have a Massive amount 400 amps if it's a 50dn if I recall. Use the power of the net bulbs pumps te whole works are easily attainable as most marine applications use 24 volt... I can't help you on the hot water heater but I can tell you our current rig holds 80gallo s of propane and I expect that to last most of the summer... Load balancing is making sure each "leg" has an equal load as you main will be few off 2 120 legs basically do t put all your eggs in one basket spread the load equally... Hope some of that helps oh and
And sure what ever inverter you buy is a "PUrE" sign wave not modified many motors and son sensitive electronics will no last long nor operate well with a modified one... And dont ask why I check the bus board at 3 am it's generally my first cup of coffee.

Keep em coming

Eric

Oh and Sean is the archival master of this board... Just an FYI he knows his stuff!!!

[Sean]

...  One concern I have is whether I'll risk burning out the alternator on my 5C with the additional load?  Is there even a risk of this?

Well, nothing is risk-free.  But the 50DN is rated for its full nameplate output continuously.  You will have batteries in the system in parallel with the alternator, so if your load temporarily exceeds the rating of the alternator, the additional current will simply come from the batteries.  The batteries will begin charging again when the load drops.  Your 50DN can supply 6.5-7.5 kW of power depending on model, which is more than many RV generators.

Don't forget the alternator was running the road air/heat blowers when the coach was in passenger service, which is probably more load than you will ever put on it.  That said, you might have the alternator checked if you have any reason to believe the bearings may be worn (probably not if your suspicions about mileage are correct).

Would I be leaving much low-cost energy on the table by not tapping into this source?

In short, yes.  Even if you don't run loads such as roof airs from the alternator while driving, this is still an important source of battery charge -- 20 times more that your solar panels on the sunniest of days.  Because the main engine is already running in a thermally efficient mode while driving, the extra ten HP or so it takes to make power from the alternator uses much less fuel than a stand-alone engine/generator would use.  I discussed this in the second half of this post:
http://www.busconversions.com/bbs/index.php?topic=7622.msg74699#msg74699

I'm quite open to going this route if it makes sense and if my noggin can handle the added complexity of tying the chassis and house systems together.

If the house and chassis systems are the same voltage, then tying them together is a simple and inexpensive process.  Several ways to do it, which have been gone over ad nauseam on this board already so I won't repeat it all here.

If the house and chassis are different voltages, then it becomes a much more involved affair.

...  If we tied it to the alternator, that would sway me toward removing the OTR air conditioner, which would free up valuable space in this 35-footer.  Not sure which way to go here.

This, again, has been extensively covered in the archives.  My take on this is that electric air can be used when parked OR when driving, whereas road air can only be used while driving.  Driving generally constitutes a tiny percentage of the time you spend aboard the coach -- we drive more than most, and it still figures to just 500 hours a year.  The other 8,000 hours we are parked.  The road air costs a lot to maintain, takes up a lot of space and weight, and is of minimal benefit.  JMO, YMMV, and FWIW.

... we haven't been to a campground before and ddn't realize it was 240.  At 50 amp, I probably shoulda known.  Can you describe how to "balance loads between the two legs?"  I'm okay with electrical stuff, but have zero experience/knowledge of 240 (except when I cobbled together my welder's NEMA plug).

At the risk of sounding like a broken record, this too has been extensively covered in the archives.  I can also recommend George Myers' excellent guide, "Electrical Systems for Converted Coaches," which addresses this and many more issues.

Since your inverter will be 120v single-phase (as opposed to 240/120v split-phase), typically the inverter is placed on one leg by itself, with all its connected loads, and whatever other loads there are, such as air conditioners, washer/dryers, electric heaters and/or water heater elements, etc. are all placed on the other leg.  Connecting the A/C to the inverter instead of the second leg while driving can be accomplished with a relay actuated by alternator output.  Lots of other load-balancing tricks can be implemented, such as those described under "energy management" on my bus pages.

Those plans are all in my head -- haven't been transmitted to the project architect because she's been tied up packing for our upcoming move.  But here's the summary:

•   Tankage = [100 gal freshwater tank under bed & 100 gallon grey/black tank in rear bay. The grey/black is made out of plywood/fiberglass (what a mess and PITA that was), spans the bay and has 3" valterra valves on both sides.  The architect / video engineer is putting together our first youtube video of this project.
•   Plumbin is pretty straight forward and is basically taken out of the Bus Converter's Bible.  The only open questions I have are (1) which pump should we buy, (2) which LP tankless heater should we buy, and (3) should I include radiator misters on a stand-alone system running distilled water?
•   We will have LP for the kitchen burners, two heaters, the water heater, and a BBQ grill on home-made sliders in the bay.

If you go with a 24v house system the pump I recommend is the SensorVSD which runs on that voltage.  It comes in two sizes and I suggest the larger 4.5 gpm.

I can't advise you on the tankless heater since I don't care for them.  My reasons detailed in this thread:
http://www.busconversions.com/bbs/index.php?topic=5149.0;all

...

I am planning on a 120 fridge due to cost.  But I found one of your posts in the archives where you mention that one may purchase a 24v fridge for about the the price as a 120vac model.  Can you recommend a supplier?

Hmm, I don't remember saying this.  Very small AC units will almost always be less expensive than equivalently sized DC units.  Total system cost for DC can be less when you consider the extra costs of inverters and other components, but even this might be a stretch.  That said, there are lots of good reasons to go DC.  For example DC units are generally more efficient, and your inverter does not need to be running to power them.

If you do go AC, then you should make sure your inverter is a true sine wave model.

I selected the 2000 watt inverter on the presumption that the AC would never be run through it.  I'm still leaning in that direction but am open to suggestion.

That's really a matter of personal choice.  I will say, though, that you have the option of much larger inverters with a 24v system.  We routinely run two air conditioners (plus all our other "normal" loads) while underway from our 4kW model.

HTH,

-Sean
http://OurOdyssey.BlogSpot.com

[thomasinnv]

I have to side with Sean on the fridge issue. We have full-timed for 4 years now, and part-timed several years prior to that. We also have a 7.5' rv style fridge. Wife and 2 kids and we often go 2 weeks or more between shopping trips.

[Sam 4106]

Hi Mike & Gigi,

I suggest you push your home bed into a corner and place a piece of furniture at the end so you only have access from one side to see if you like that arrangement. I know every inch is precious in a bus but I don't think you will like your planed arrangement.

I don't know how tall either of you are or the ceiling height of your bus but adding 1.5" of insulation and 3/4" to the floor seems like you are sacrificing too much head room. Do you really need 3/4" plywood over the rigid foam? I think 3/8" would be enough and be half the weight. Not everyone thinks about the weight issue when converting a bus.

When will you be in Minnesota? We are members of Midwest Bus Nuts chapter of Family Motor Coach Association and there will be a rally at Wisconsin Dells May 18-20 if you would like to see a few buses. Some are professional conversions and some, like ours, are home conversions. You have already done a great job of planning but you would probably benefit from seeing other buses and talking to the owners. Our rallies have gotten smaller with the high cost of fuel so I expect only 10 or so buses. Saturday would be the best time to look at buses as Friday is arrival day and some people leave early Sunday morning. Hope you can make it.

Good luck with your project, Sam MCI 8 (formerly Sam 4106 until we changed buses)

[Oonrahnjay]

I suggest you push your home bed into a corner and place a piece of furniture at the end so you only have access from one side to see if you like that arrangement. I know every inch is precious in a bus but I don't think you will like your planed arrangement.  (snip)

      Yeah, that's one of the first "requirements" that The Management laid down.  She said "I'm not crawling around a bed trying to put sheets on the corner of a mattress stuck way back where I can't get to it".  So our bed is a pedestal in the middle of the floor with an aisle down each side.  And it's a California King.  She was right about that, too.  (The issue of who is going to crawl over whom to get up to go to the bathroom is also something to think about too.)

[Midwilshire]

I suggest you push your home bed into a corner and place a piece of furniture at the end so you only have access from one side to see if you like that arrangement.

We've had both arrangements before, and Gigi likes the current design.  She-who-must-be-obeyed hath spoken.

I don't know how tall either of you are or the ceiling height of your bus but adding 1.5" of insulation and 3/4" to the floor seems like you are sacrificing too much head room. Do you really need 3/4" plywood over the rigid foam? I think 3/8" would be enough and be half the weight. Not everyone thinks about the weight issue when converting a bus.

I had selected 3/4" because that's what Mike802 used.  http://www.busconversions.com/bbs/index.php?topic=22010.0  But now that you mention it, his had to be structural, since he tore up the old floor.  Since I'm planning to leave the exiting floor, 3/8" plywood should work.  Thanks.

there will be a rally at Wisconsin Dells May 18-20 if you would like to see a few buses.

Dang, I'll be pulling in around the 23rd.  Staying until around 1 July.  Lemme know if anything else is going on during that time.

-Mike