AC/DC Fridge vs DC only.

[daveb]

If I'm only running the inverter for a limited time I don't even worry about tripping the breaker off. I mean the fridge only cycles now and then anyway. If I'm on the road I also don't worry about it; the alternator is charging. To tell the truth about the only time I use the big inverter is when the micro is running...during long run times I usually have the engine running anyway. For the little things that run for hours I have a few small standalone inverters.

[COkid]

Another twist to consider...
Our AC/DC Norcold fridge has a Danfoss compressor. The compressor runs 'natively' on 12 VDC. So, when you're running off the coach inverter there are two conversions involved:
12 VDC to 120 VAC by the coach inverter
and then 120 VAC back to 12 VDC by the converter in the fridge to run the compressor

I also used an ammeter to check current draw. The fridge uses less current running off DC.

Net: I pulled the fridge out and unplugged the AC cord. I run the fridge on DC only.

Regards,
Alan

[jage]

Originally Posted by COkid

Net: I pulled the fridge out and unplugged the AC cord. I run the fridge on DC only.

I put a switch on my fridge outlet so that I can have it on 120v when on shore power.

[BroncoHauler]

Originally Posted by jage

I put a switch on my fridge outlet so that I can have it on 120v when on shore power.

Hasn't your SMB been on shore power for 2-3 years now?

[KTMRIDER]

Originally Posted by BroncoHauler

Hasn't your SMB been on shore power for 2-3 years now?

[boywonder]

Originally Posted by Viva

I guess there could also be a way to wire the refrigerator (AC/DC one) so that when on shorepower it would run from 110, and when on inverter/battery it would run on DC, but my brain is feeling overstretched at the moment I only have a charger (not inverter) so have not figured this out for my own rig.

I suppose that you could wire a dedicated 110V receptacle for the fridge directly from the shore power inlet (before the transfer switch) with a appropriate breaker. It would be completely separate from the 110V inverter outlets and would only be live when plugged into shore power.

[DCHitt]

boywonder
I think we could call that "Best Practice". The simplest solution is to just pull the refrigerator 110 ac plug.

[Brett218]

I have the AC/DC truck fridge in my van. I like having the option to plug in just the fridge when I'm parked at home between big trips. I am not wired for shore power, just 300 watts of solar. Taking the fridge off the batteries at night seems like a good thing

I still drive the van once or twice a week to go surf so it always has cold beers in the fridge. I'm really pleased with the quality of the truck fridge. Very quiet and its only pulling about 5 Amps when its duty cycling.

Thumbs up for the AC option

[daveb]

Originally Posted by boywonder

I suppose that you could wire a dedicated 110V receptacle for the fridge directly from the shore power inlet (before the transfer switch) with a appropriate breaker. It would be completely separate from the 110V inverter outlets and would only be live when plugged into shore power.

At least a dedicated outlet would be a good backup for the fridge (or anything else) just as protection if the transfer switch in the inverter fails. But I have solar and the DC fridge can run that way until I get back. One thing I won't do on a regular basis is to over run and put hours on my expensive inverter. Besides time and use, letting my inverter operate in temps that commonly jump to 120* during the day is not something I want to do. The inverter is off when the transfer switch is closed. I've had my inverter trip due to high heat while in use. There is a reason why they have fans in them.

[rean1mator]

exactly how much of a delta is there between running it off ac vs dc?

still trying to figure out best options. I did end up buying the ac/dc version of the truckfridge.
I may just keep dc unplugged for now until i find a permanent solution.

i like jages idea of using a switch and also boy wonder's suggestion to wire in a separate 110v outlet direct from shore power connection.

i've got solar panels delivered today and i'm off to death valley for a week on my first trip in the van so will have a better understanding of my needs after the trip.

Originally Posted by COkid

Another twist to consider...
Our AC/DC Norcold fridge has a Danfoss compressor. The compressor runs 'natively' on 12 VDC. So, when you're running off the coach inverter there are two conversions involved:
12 VDC to 120 VAC by the coach inverter
and then 120 VAC back to 12 VDC by the converter in the fridge to run the compressor

I also used an ammeter to check current draw. The fridge uses less current running off DC.

Net: I pulled the fridge out and unplugged the AC cord. I run the fridge on DC only.

Regards,
Alan