AmboVan Restarted

[r_w]

That is why ambos have high-idle functions.

 

[Betarocker]

Does that AC unit have the ability to run in reverse to create heat in the winter? (AKA Air Source Heat Pump)

 

[hobietony]

Does that AC unit have the ability to run in reverse to create heat in the winter? (AKA Air Source Heat Pump)

Nope - AC only. I don't expect to camping where I need heat, and I also have access to a hookup. I think the Propex will be a much quieter and efficient heat source in general, but if I am at a hookup, an electric space heater will work also.

 

[McZippie]

400AH in the house bank, I don't expect to run it off the battery alone, but while the truck is running/driving. I seem to recall you have some vehicle electrical expertise, is there some math I can do to figure it out?

Assuming it's a 13,500 BTU RV AC at full power would pull about 13.5 to 15 amps.
Assuming you have very good batteries and wires.
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Using this Peukert Effect calculator = AC run time of 7.75 hours at 50% battery discharge rule.
http://http://www.csgnetwork.com/batterylifecalc.html
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Whack off another 20% of above time for inefficient inverter and battery banks are seldom fully charged, numbers show maybe get 5 hours of run time with a 3000 watt pure sine wave heavy duty inverter, that can handle 6000 watt compressor start up cycles.
My gut from experience with running other high amp loads, getting anywhere near a 5 hours run time would be impossible.
.
Real world:
1. A 2000 watt inverter won't run it, alone or with an engine alternator boost.
2. Upgrading to a heavy duty (expensive) 3000+ watt inverter, still leaves a few problems.
a. Stock OEM alternators are not designed for running continuous high loads.
Does your Rig have an aftermarket high-output continuous duty alternator???
b. Once the 400 amp battery bank is discharged, it would take many hours to recharge.
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All the above is why Motor Homes run a generator while in route to power the roof top AC and shore when parked.
(Smiley face with hands pulling hair out ...crap)

 

[McZippie]

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So, with the engine running, and no shorepower, I tried to fire up the 120v house AC, took a couple tries, and I needed to let the fan spool up first, but it caught and I was able to get cold air blowing. Unfortunately, even with the engine over 2k rpms, I still had a negative draw from the house batteries, pretty clear that this is not going to be a sustainable function. I suppose that is what the van AC is for anyway, and with the loads of insulation I added, should be less of a problem to keep it cool while driving.

Looks like you found out, what I was trying to explain with my latest post.
(Smiley face with eyes rolling ...crap )

FWIW our little Rig has 3 AC Systems, Bus 30,000 BTU with separate compressor condenser , Ford dash and Semi Sleeper Cab 120 volt outside condenser unit. Dual high output continuous duty alternators.
I given up as unpractical trying to run the 120 volt AC from batteries/inverter.

 

[McZippie]

.... And Tony one more FWIW, while you're still in the building stage, consider a built-in generator to power the AC.

It gets mighty hot in your part of the world and Diesel engines radiate a lot of heat for hours after they are shut off.
I tried to build our Rig without a generator and failed. Now that we have one I like it a lot!
We never camp with shore power, and run the geni about 45 minutes each day to heat water, wife blow dry hair, microwave and fast charge charge battery bank. If its real hot out, run longer for AC.

Guess those Class C Motor Home builders do know a thing or two.

 

[hobietony]

^^^ I intend to get a 2.5k-ish Honda-type generator, and though there is not really a place to store it 'built in', a box/cage on the back door seems to make sense.
Whatever I get, I want to be able to run off the propane so I don't have to carry three fuel types.

Thanks for the input, I recall you went through a lot of this on your build

 

[McZippie]

^^^ FWIW ....if going with a stand alone geni, get a Honda 3000 watt inverter generator or Yamaha 3000 watt. You'll need the 3000 watts to power the AC and not have any start up compressor issues.... Assuming your AC is 13,500 BTUs.

They Honda's come in two models, newer 78 lbs pull start and older 134 lbs electric start that be can be aftermarket modified for remote starting.
.
The Yamaha's also have pull and electric start models, weigh in at about 135 lbs. and 150 lbs. The electric start also has a Yamaha remote start option.
.

 

[VanIsle_Greg]

IIRC there were a few brands of generators out there that run on LPG too. Now that would be a sweet setup on a Diesel rig not to have to carry Diesel, Gas and Propane with Gas only for the generator.

Quick google search resulted in a bunch of them from Homeowner occasional use to HD Commercial units.

http://www.homedepot.com/p/Generac-...ortable-Generator-6000/202938503#.UhgdVj-1cZl



$699...not bad and a LOT of good reviews.

 

[ben2go]

When I click the link it has $609 each.It may be priced differently by state.

 

[VanIsle_Greg]

When I click the link it has $609 each.It may be priced differently by state.

Yeah, my bad...it is $609.00, even better! Seems to power through a lot of LPG in a 9 hour period however?

 

[hobietony]

Water system...
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Tank secured, built a wedge piece to pin the top of the tank, and some aluminum angle to pin the bottom. Seems pretty immovable

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Fill and vent from the exterior

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Initial layout of the pump system, I say initial because, despite how nicely this lays out in the space available, it will not work with the pump blowing air into the tank instead of sucking water out

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After chasing down a couple leaks, final arrangement is as shown below...

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Sink mocked up for layout purposes, final countertops will be one layer of 1/2" ply and one layer of Corian solid surface countertop.

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Grey water direct exit out the bottom, made an aluminum sleeve through the flooring that can be caulked to the underside, with an inner sleeve that can be caulked to the outer one. Flexible plastic above and below, double hose clamped to the sleeve. Also had to build a chase to house the drain line, and keep it and the supply out of the ski storage below the sink.

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Whole layout

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Little boxing out to do to isolate underside of the sink from the ski storage it intrudes into, but the water goes in and the water goes out, what more could you want? BTW, Greg, that Ecotemp water heater looks pretty awesome, not going to be able to incorporate it into this phase, but I think it will be pretty easy to set up an outside shower on the drivers side, water supply and propane are right there. Spouse is on board with it as well.

 

[hobietony]

Continuing the dial-in of the Inverter/Charger...
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So I thought that the compartment that I mounted the unit in had enough ventilation, but it seems like no. I got a temperature fault while I had the charger plugged in, running the AC, etc. So, looks like I need to add some positive ventilation to the compartment. Found a pretty high CFM computer fan (sez 79cfm on the box), a simple switch for now, and power that is hooked up through the house panel. Wanted to not just cut a hole in the floor of the compartment, this leads to exterior space, and seems like it would be pretty easy to get water up in the fan and compartment. Put the fan on a 6" extension, and put a shield over the bottom to block direct debris from the duallys. This is also in line, generally, with the outflow of the internal fan of the inv/chg unit.

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Got some suggestions from Bevan (Oxrockrat) on how to hook this up thermostatically, need to dig into it a bit more. In the meantime, it is powered when the house panel is on, and can be switched off manually. Need a bit more follow up work here, but enough to see if one fan is good enough

 

[ben2go]

If you have problems with smells coming from your waste holding tank,make your own deep P traps so the water can't run out while driving.

 

[Abitibi]

If you have problems with smells coming from your waste holding tank,make your own deep P traps so the water can't run out while driving.

There was another ambo at Expo who had a sealing cap mounted flush to the floor for that same purpose. Just something else to keep in mind.

But that beast is starting to take shape, looking great!

Cheers
Mr. D