Using DC to DC charger to run AC ???

Rbertalotto

Solar Addict
Joined
Nov 26, 2019
Messages
232
Is this possible. Rather than using an outboard generator to run the AC unit on my travel trailer, can I run it off a 40A Renogy DC to DC converter running off my trucks alternator. The AC unit on the travel trailer will run on a single Honda E2000i Inverter Generator.

Here is what I have:

200Ah of AGM deep cycle battery (100Ah usable) Soon to be replaced with 300Ah of Lithium .....
2000w Inverter
220Amp alternator in truck
Renogy 40A DC to DC Charger

Running the truck is much quieter than running the Honda generator. (The Honda generator can not run in the quieter ECO mode and run the AC)
Will the 40amps the Dc to DC converter is putting into the battery, keep up with the discharge of the battery by the inverter.

Thanks in advance
 

Bud Martin

Photon Sorcerer
Joined
Aug 27, 2020
Messages
2,108
How much power does the Aircon needs to run and the startup surge it needs to startup?

"220Amp alternator in truck" what is the rating at idling?
 

Rbertalotto

Solar Addict
Joined
Nov 26, 2019
Messages
232
I never measured the current needed. But it runs on a Honda 2000. I installed a sofisticated "soft start" device on it so it can run on a single 2000 generator. Works great! But running off the truck would be much better. The new Ford F150 hybred has a feature that allows exactly what I'm trying to do.
The truck I have has a new "smart" alternator and will out put whatever is needed at any RPM up to 220 amps.
 

Bud Martin

Photon Sorcerer
Joined
Aug 27, 2020
Messages
2,108
Renogy 40A DC to DC Charger is about 500W of power (for 12V system), so if the Aircon uses more than that then it will also draw power from battery to keep up with the demand, so if you use more than the charger can provide to keep the batteries charged up then you will drain the batteries, that is why you need to find out how much power your Aircon uses.
 

tazmann

Solar Enthusiast
Joined
Sep 1, 2020
Messages
109
Without the Dc to Dc charger, going direct to AGM's maybe . but if your limited to the 40amps @12volt and running standard rv roof air you will be out of battery within a couple hours
 

noenegdod

Solar Addict
Joined
Mar 21, 2020
Messages
646
From an efficiency perspective this is insane. The truck engine all on its own just idling and doing nothing will consume somewhere around .5 gallons of fuel each hour or more, adding 500 Watts of load to that will increase consumption.

A Honda 2200 on 1/4 load which is 450 watts will run for 8 hrs on .95 gallons.


If you do this a couple days a month, who cares. If you do it every day it makes no sense.
 

Rbertalotto

Solar Addict
Joined
Nov 26, 2019
Messages
232
Understood. Only would be used on very hot days for a couple hours. I'm never in the camper during the day. I use my toy hauler as a means to an end. Motorcycling during the day or shooting cowboy action. When I get back to the camper at 4pm it might be hot enough that it needs a couple hours of cool down. The extra gas matters not.
 

noenegdod

Solar Addict
Joined
Mar 21, 2020
Messages
646
The other nice thing about running the truck instead of the generator is the fact that the exhaust goes through a catalyst and even though you are burning at least 4x as much fuel the exhaust is far less smelly.
 
Top