Installing an Inverter to run fridge?

[sail268]

Is it feaseable to install an inverter to run the fridge? I have a Catalina320
with 2 4d Batt. I'm not sure of the amp. draw of the compressor.

[Freesail99]

It may be feaseable for day sails maybe a weekend. But not long term. You may not have a big enough bank, as I don't know what else your running.

[sailingdog]

Not a good idea. An inverter isn't very efficient...wastes a lot of the electricity as heat... You'd be much better off running a 12 VDC refrigerator off the batteries, since you won't have the conversion losses of the inverter.

[camaraderie]

With 2x4D batteries you hve an effective A/H usability of 160 or so. A typical 12V refrigerator with a well insulated box will draw 50-100amps a day. The smallest "dorm cube" type AC refrigerators use about the same amount of power daily....but there is a significant efficiency loss running a large inverter full time so I would guestimate that you could get a day or a day and 1/2 max out of a small A/C fridge run by an inverter off your battery bank. On the other hand...you can get one for $100 bucks vs. 1000 or more for a 12V system.

[Valiente]

I just bought a pretty substantial inverter/charger that I intend to mate with a fairly ridiculous amount of battery capacity. But I did it to have AC reserve, not to customarily keep the AC boat circuits energized. The reason for this is that I want to have the ability to use AC power tools and to charge small tools and chargers via AC when I wish to...and to run a 1.5 gallon ShopVac to keep the cabin clean and perhaps the occasional use of the microwave or a kettle.

But the vast majority of the usage will be DC and I will normally keep the inverter off, because it draws a fair bit of power just to energize the boat's AC panel.

DC refrigeration is bad enough in most circumstances: I can't imagine, even with the capacity I am building in, that I would run a continuously cycling AC appliance on my boat. It's far better to spend money on insulation and a proper install of an Engel, an A-B or a NovaCool system...they are quite efficient and certainly draw less power.

There are $50-$100 "auto" type inverters about the size of a thick book that will suffice for most boaters, and which can run a Dremel or some other small tool for a while. There are also the "power pack" AGM batteries with inverters that can supply 700 watts or so. I have both as backups.

[sail268]

I hear what your saying, but I do not want to add an addtional refridgerator since I already have the factory unit on the boat.

This would only be for day sails and overnight.

[sailingdog]

The factory unit is AC only, not dual voltage???

[Sailormann]

Is it feaseable to install an inverter to run the fridge?

It is possible yes. It is not smart, unless you want to run the engine a lot to charge the batteries. Buy a cooler, use ice.

[Alchemist909]

The stock Adler Barber fridge on a C-320 runs off the batteries, and doesn't use 110 VAC.

To use your fridge when "off the grid", just use it. There is nothing you have to do except make sure that your batteries are fully charged.

Unless your batteries are severely compromised, you can get a couple of days running the fridge on one battery before you need to recharge that battery.

Steve
Alchemist C-320 #909

[sail268]

Thanks Alchemist909, I should have checked my manual. That solves my problem. I'll keep an eye on Batterys and maybe install a larger alternator.

Thanks again, Dave