Will the 2800w inverter in 2016+ "all electric" Newmars run 1 AC?

[tjZ06]

In some of the newer all-electric coaches with bigger inverters I know that 1 AC can be run off or the battery bank.

Is this the case with the 2016-17 Newmars with the all-electric option and the 2800 Watt inverter? Is the wiring even setup to allow this?

I have friends with coaches setup this way and it's super nice for going down the road on a hot day. You obviously run the dash AC, but then you can also run 1 house AC to keep things nice and cool, and the engine's alternator is charging the house battery bank as you drive so it doesn't drain your house bank.

Thanks,
TJ

[GaryKD]

Hi tjZ06,
The answer is no. Contact Newmar CS and confirm.

[Sidewinder4]

Originally Posted by tjZ06

In some of the newer all-electric coaches with bigger inverters I know that 1 AC can be run off or the battery bank.

Is this the case with the 2016-17 Newmars with the all-electric option and the 2800 Watt inverter? Is the wiring even setup to allow this?

I have friends with coaches setup this way and it's super nice for going down the road on a hot day. You obviously run the dash AC, but then you can also run 1 house AC to keep things nice and cool, and the engine's alternator is charging the house battery bank as you drive so it doesn't drain your house bank.

Thanks,
TJ

Here is a YouTube on the technique and information recently posted about the same issue. I believe the answer is yes, but you are going to need some hardware.

https://www.youtube.com/watch?v=B0rZY5uotKI

Hope this helps you.

[slabman]

A 2800 W inverter can only put out about 20 amps at 120V. Since these roof airs can consume around 14-16 amps, with a 17 amp or more startup, this application would essentially use up the Magnum's inverting capacity. And, as mentioned in the video, you need to take away the initial current surge so you don't fry that Magnum. So then...how we gonna run that refer? Maybe put in an LP tank and go back to an ammonia refer? Probably will need to get your fire extinguisher ready?....

To the O.P....yes, the Prevosts are set up to run one or two roof airs, but they do have higher capacity battery banks, along with multiple alternators (3-4) and inverters. The only "plastic" coach I know of that can run off the inverter while going down the road is the King Aire. But this isn't an ideal situation in my mind, since I think power consumption is greater than what the alternator can put back in. As someone mentioned, the newest Kings have a 350A inverter, but I believe it might still fall short in balancing power in vs power out.

I thought that video was interesting in using solar to power the roof air. But I think he still has a problem, since he burns more power than the solar puts back in, meaning at the end of the day he'll have discharged batteries. Since the sun goes to sleep at night, he'll need to find another way to put that power back into his batteries. Is plugging into shore power legal in that scenario?

The day is probably not too far off when you'll see Newmar or a competitor add another alternator/inverter setup and we'll have an oem offering of a way to run that roof air. Sure would improve things on those hot, humid days....

[newmarpusher]

Our 2015 all electric Ventana can't run any house ACs off the inverter.

Why don't you just run the generator to power BOTH ACs?

That's what we do when the temps are warm.


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[Mr_D]

Running one heat pump off the batteries was an option in our Magna (we don't have it). They went with a bigger alternator, 2 more 8D AGM's (for a total of 6) and a second 3000watt PSW inverter.
Our last Dutch Star was not able to run the heat pumps off the inverter.

[Tomp4801]

+2 on running the generator.... Use it or lose it!

[CapuTech]

There was a couple at Camp Newmar this weekend who modified their Ventana to run one air conditioner off an inverter. However, he had made some significant modifications to do so.

First, he replaced the 2800W inverter with two - one 3000W and one 600W specifically for the fridge. He also replaced his batteries with 500AH worth of Lithiums. He can drain these to 20% so has as much capacity as my 8 AGMs. Also, lithiums do not have the voltage sag that lead acid batteries do, and that's a big deal on heavy loads like this would be. Finally he had 1300W of solar.

He told me they can usually boondock without using the generator much at all. He can also drive down the road with one AC running, and the solar plus alternator is able to keep the batteries from draining too rapidly when he does.

Without this sort of modification, the answer to the original question is no.

[newmarpusher]

Originally Posted by CapuTech

There was a couple at Camp Newmar this weekend who modified their Ventana to run one air conditioner off an inverter. However, he had made some significant modifications to do so.



First, he replaced the 2800W inverter with two - one 3000W and one 600W specifically for the fridge. He also replaced his batteries with 500AH worth of Lithiums. He can drain these to 20% so has as much capacity as my 8 AGMs. Also, lithiums do not have the voltage sag that lead acid batteries do, and that's a big deal on heavy loads like this would be. Finally he had 1300W of solar.



He told me they can usually boondock without using the generator much at all. He can also drive down the road with one AC running, and the solar plus alternator is able to keep the batteries from draining too rapidly when he does.



Without this sort of modification, the answer to the original question is no.

For boondocking, I totally understand making such modifications to be able to run an AC on battery power.

But running down the road as the OP asked about - generator all the way. I can't hear mine with the air running and haven't been able to notice a measurable change in mpg with the generator on or off.


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[Sky_Boss]

Originally Posted by tjZ06

...
I have friends with coaches setup this way and it's super nice for going down the road on a hot day. You obviously run the dash AC, but then you can also run 1 house AC to keep things nice and cool, and the engine's alternator is charging the house battery bank as you drive so it doesn't drain your house bank.

I am very suspicious of the claim that your friend has an AC running on the inverter. I think it would take a major electrical rewire for such a set up or a separate/spare inverter totally dedicated to do this. It just doesn't make any sense at all to me.

I'm betting they had the generator running. Of course, I could be wrong but...

[Rd1]

Originally Posted by slabman

A 2800 W inverter can only put out about 20 amps at 120V. Since these roof airs can consume around 14-16 amps, with a 17 amp or more startup, this application would essentially use up the Magnum's inverting capacity.....

Slabman, good observation, there is obviously a point when the practicality goes out the door. However, if the objective was to just use the AC on a hot sunny day while driving down the road, would, say 1200W of solar and 8 agm and 2.8-3k inverter (plus the alternator) be sufficient just for that purpose? granted the fridge and if present the basement freezer would be taxing the system as well. thank you for your insight.

[vsheetz]

Yup, we run the genny to power the AC if needed when traveling.

[tjZ06]

Thanks all. After doing some more research, and speaking to a few friends with this setup you are all right: the factory inverter cannot run an AC and do it's other jobs (particularly keeping the residential fridge running).

My friends that do have this setup have a 2nd, dedicated 3k inverter just for the AC. It also involves some messing around to get the HVAC controls setup such that they only run the 1 AC when on inverter power, and ensuring it's switchable etc.

All-in-all I guess it's just worth running the genny when driving!

-TJ

[ghaynes754]

Don I'm still in my Airstream Classic. But I can run the AC with the following setup. 740W solar, Magnum 3000W Hybrid Inverter, 400ah of Lithiums. Draw on the AC (15K Penguin) is about 130ah DC while running. So with no solar input the batteries will run a couple of hours. Solar input on a bright day will put in about 40ah extending the batteries.

If I need to do a longer run time a single Honda 2000 will give me an additional 90ah or so into the mix.

The Magnum is run to a sub panel that holds the one AC unit and other appliances like microwave, electrical outlets. A single Magnum can't run everything at the same time, likely why the King Aire has two inverters.

What makes the biggest difference overall is that the Magnum Hybrid will take input from three sources (solar, generator/shorepower and batteries), mix it all together and manage the input loads efficiently. Standard Magnums won't do that.