Running AC without a generator

[opus]

Generator while driving would be best. A whole lot more simple than fussing with an inverter and such....cheaper too.

[wtd]

Originally Posted by opus

Generator while driving would be best. A whole lot more simple than fussing with an inverter and such....cheaper too.

Yup ...

[bus-bro]

You could probably do one 9000 btu AC off an inverter while driving.

Off the top of my head: the AC would be about 7 amps running, with a couple of 0.8 inefficiency factors, that would be about 100 amps of 13 volt current. So if the altenator could do that most of the time, plus running loads, it could work.

[chev49]

You can check on the bus conversions magazine forum. There are a couple of daily posters there that would probably diagram it all out for you.

[Motobus]

I was in a business that rebuilds alternators and generators picking up some lenses the other day and ran that by the owner. He said it wouldn't work. He had a FedEx driver that tried with some inverters that mathmatically could do the job and even added an alternator to his truck. The guy spent 2K or better and couldn't get it to work. I'm sure it is possible but not practical.

[Chadluc]

buy a belt driven generator head ...around( 800.) from northern tools or such. Will do the job fine

[lornaschinske]

Originally Posted by Chadluc

buy a belt driven generator head ...around( 800.) from northern tools or such. Will do the job fine

I can't tell you about buses but our Eagle coach had a fantastic HUGE AC/DC generator/alternator in the rear engine compartment. It were there to run the huge AC OTR air conditioner. David forgot to load the thing into the Blue bird when we left NC. I Don't think we could have used it on the Blue Bird (FE). It was huge and we could have used it rather than a generator.

If you already have a generator that will run your AC unit(s) then why bother with the expense of adding the other stuff? Don't say "save on fuel" because you will use the fuel with the increased drag or the alternator. I figured it all out (it worked out on paper) and had as much invested in inverters and excess batteries. We will be going with a generator mounted up under the rear of the bus to power a window air conditioner that we will "remodel". We will add an auxiliary fuel tank (ABS Valterra Rocket tank), quieter muffler and a home made "genturi"... because I would like to wake up the next morning without a chalk outline drawn around me.

[bus-bro]

I'm going to call you all up on a bet here . I will install an engine driven alternator air condiontioning system on my bus . I figure $2000, not including AC unit .

[wtd]

Originally Posted by bus-bro

I'm going to call you all up on a bet here . I will install an engine driven alternator air condiontioning system on my bus . I figure $2000, not including AC unit .

Oh my - a sucker bet

Sure, you can do it ... it's just that 2 grand it'd run you...
I could buy 7 generators for that and they'd each do the same thing with less muss and fuss - put one on a hitch carrier, pull the string and plug in your A/C.

OP's question was phrased this way "Would to be logical or practical to run 2 ACs off of inverters? (when driving down the road)" (italics mine).
Just my opinion, but no, not the way the question is put. No disagreement at all that it could be done if you wanted to do it for whatever reason.

Tom

[lornaschinske]

Also some folks get things at a very good price while others of us can't or don't have the resources. So that would be a silly bet. But if you can, then why haven't you done that? Or tell us how you can or did do it and WHEN you did it. I have a link to a page that says a guy put a homebuilt hydronic heater in his travel trailer for $355. His most costly thing was an Hartell circulating pump for $155. These are 1991 prices. By reusing the rear heat exchanger from the bus along with the original coolant hoses, we can omit some things (like the fans, radiator) and we have an old RV water heater we can use. So that leaves me with locating a hot water circulating pump. Which will cost me more than the 1991 prices. (I lost all my bookmarks so I don't know what one will cost). When we do our hydronic system, I WILL post the hows (along with pictures). Because this is something lots of folks will want to know about. Whether they choose to do it or not is up to them. And there will be some that improve upon what we do.

My big question is, if you know how to do it, then why haven't you posted HOW? Knowing how to run an AC air conditioner unit without a generator is something many converters would be interested in.

[bus-bro]

Geesh Lorna, I said I'm going to do it, not that I had done it, not that it's that big a deal. I'll have the inverter system anyway, I'll just plug in an AC and see if it works. Pretty standard stuff: battery bank, inverter, and cabling to charge the house bank from the engine alternator. (I've installed the battery bank and cables already, just need a sine wave inverter.$$$) I've got a 160 amp alternator on the bus, so at road speed it shouldn't be a problem. If I was in stop and go traffic I'd turn the AC off.

.

[gbstewart]

anything can be done if you want to spend the money, engine driven generator head would be better way to go cheapest, but you have to wonder how much power it would take to run it off the engine? aswell would much drag a extra alternator that is working hard? I just run the generator with the a/c running works good.

gbstewart

[bus-bro]

My point is that I'm going to have a battery bank powering an inverter that can use the alternator for charging anyway. Might as well plug an AC in and see if it works. It's no extra expense, outside of a beefier sine wave inverter.

[wtd]

Originally Posted by bus-bro

My point is that I'm going to have a battery bank powering an inverter that can use the alternator for charging anyway. Might as well plug an AC in and see if it works. It's no extra expense, outside of a beefier sine wave inverter.

Long as you're most of the way already, what the hey, sounds like a good plan ...

[Jarlaxle]

Most skoolies will have 90-100 amp alternators. Generally, the newer the bus, the bigger the alternator. Any bus with road A/C will have a bigger one, any bus with DUAL road A/C will have a REALLY big one (mine, with dual A/C, is 175A). Any truck that has to run big loads (liftgates, winches, a DPW truck or trash truck with bunch of strobe lights) while idling will also have a big alternator (and often, a third battery). Most of the time, they are factory options and will bolt right up to a skoolie engine & wiring harness. (Standardization is a wonderful thing.)

Note: DO upsize the wiring if you do this! I would go for, MINIMUM, a dedicated 2-gauge wire with fusible link from the alternator to the inverter, and would prefer a 1/0 gauge or better. I would figure the A/C load (remember the massive startup draw), add 50%, and wire for that.

[thommassey]

Originally Posted by chev49

You can check on the bus conversions magazine forum. There are a couple of daily posters there that would probably diagram it all out for you.

Is this forum within Skoolie.net or is it a separate page? I could not find it here...