AC - Briefly Leaving Dog In Van

[avanti]

Originally Posted by booster

I would put one qualifier on a lot of the discussion, I think.

If, and how long, a battery bank will run the AC is greatly influenced by what state of charge you start out at. Most batteries rarely, if ever, truly get to 100% full, except lithium, due to the long charge times needed for the last 20% of the charge to full. Realistically, I wouldn't use full as a starting point in the real world, unless you just stopped driving after 8 hours, or have a charger that is capable of charging to all the ways full, which many aren't.

We have 440ah of AGM, and it will start the CoolCat AC at 50% full, but the voltage is getting to being close to dropping in the inverter cutoff range (Magnum MS2000 pure sine wave). This would indicate to me that if you had 200ah of AGM, you would be close to not starting the AC if you down much, and where the cutoff voltage of the inverter is set. Once running, the amperage drops and the voltage goes back up a ways, so then would run a while until it cycled the compressor, which would leave a hot doggy.

All true, and a good reason to add a bit of solar to the mix. However, OP only wants 30 minutes of air, and all of my assumptions have at least doubled that, so there is significant head room. Like all such things, such a system needs to be properly designed. I am just trying to argue agains exaggerating the difficulty of what is in fact a very achievable goal.

[jon]

I want to offer a slightly different point of view. One could look into installing a 12 volt dc air conditioning system that uses a fraction of the electricity on a large roof mount 120 vac air conditioner.

I installed a 8000 BTU 12 volt air conditioner that draws less than 40 amps from my 12 volt battery pack. A roof mounted 12K BTU typical air conditioner would probably draw well over 100 amps.

Sure it wouldn't be powerful enough to cool in hot direct sun, but it keeps a pre-cooled van livable for a long time. My calcs say that I can run it overnight but I haven't had a chance to test.
Jon

[Oliver2017]

[QUOTE=markopolo;65720]There are lots of great points and advice in this topic. I'd summarize it like this:

1. Yes, 30 minutes of A/C on battery power is obtainable both on production units and DIY retrofits.
2. Don't assume 100% reliability as there are many parts in the system and any of them could fail without any warning.
3. Remote monitoring via smartphone is perhaps a must if trusting the system for pet care.

I appreciate all the advice and great points made. I'm thinking my best option is to purchase a camper van that has an UHG and leave the van idling for the rare occasions that I need to leave my dog in the van for a very brief segment of time. I'm thinking a regular generator would be too noisy in a parking lot and draw too much attention to my van. Please share your views if I am mistaken on my best option.

I posted the question because I had recently got the dreaded call that I needed to get to the hospital asap to be with a relative. With no time to plan out my trip and research pet friendly hotels, I was thinking I might end up having to car camp. Along the way, I had to stop at a rest stop and it was way too hot to even think of leaving my dog to do more than what a bottle could handle. While at the rest stop, I spotted a camper van (never really noticed them before) and I was totally sold on the concept. I kept thinking what good is one if I still have no way to safely leave my dog for even 15 minutes...30 was the safe cushion zone.

[booster]

If you are going to leave the van running, you don't need the underhood generator, as you have the dash air to use.

[Oliver2017]

Do I need remote start? Sorry...I'm pretty much clueless on how to leave it idling without leaving a key in the ignition. I was thinking if I run the roof top AC...it would not seem like the van is unoccupied and it would drown out the idle sound.

[DCHitt]

[QUOTE=Oliver2017;65751]

Originally Posted by markopolo

I appreciate all the advice and great points made. I'm thinking my best option is to purchase a camper van that has an UHG and leave the van idling for the rare occasions that I need to leave my dog in the van for a very brief segment of time. I'm thinking a regular generator would be too noisy in a parking lot and draw too much attention to my van. Please share your views if I am mistaken on my best option.

If you use the idle option you don't need the UHG. Use the dash AC and if you want more install a rear evaporator/fan. The AC will be then driven directly from the engine and eliminates the need for big amps, big battery, big inverter.

[booster]

Originally Posted by Oliver2017

Do I need remote start? Sorry...I'm pretty much clueless on how to leave it idling without leaving a key in the ignition. I was thinking if I run the roof top AC...it would not seem like the van is unoccupied and it would drown out the idle sound.

Remote starters are a very common and relatively inexpensive aftermarket device. They are designed to run the vehicle with no key in them, and usually will kill the engine if someone tries to move the vehicle, if they do get in. Many towns require you to have an autostart with no key in the ignition if you are prewarming or precooling the vehicle.