Inverter Output

It will draw 88 watts when running. Watts are a measure of power used.

What you need to know are: How many amps the refrigerator draws at startup (lock rotor draw), how many amps the inverter is capable of outputting at it's maximum, and if the maximum output has enough duration (time) to overcome the startup draw. You should also allow for some loss through the inverter (typically 10% in real world).
You can convert the above back to watts at 12v. Watts= volts X amps.

Reading between the lines here but you have almost identical the amount of watts that my Kill-A-Watt displayed when hooked to my dorm fridge at 120v. What happened when I tried to install an inverter was that my 600w inverter was unable to overcome the startup draw. Since the inverter's rating was 1200W, maximum, it should have been enough but the "duration" of the maximum was not enough, the inverter would go into protection.

Since I planned to use an inverter for some other low-watt 120v devices, I upgraded to a larger 1000w inverter. I may have been able to buy another 600w inverter that would have run the fridge but price is negligible in these classes of inverters. All is running well now.

The 600w inverter was a Samlex SW series, pure sine. The 1000w inverter is a Xantrex Prowatt pure sine. Good luck with the inverter installation!

88 watts.
Watts = voltage times the amperage

So you are using less than an amp at 110; you will use +-8 amps at 12 volts.
But is the 88 watts AC just for the controls while running on GAS or are you going to use a 12 volt heat element?
Seems to me a 12 volt heat element will draw more than 88 watts.

So more details would be helpful