Fridge on Inverter

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Jan 9, 2008
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North Pacific 45
Help! I cracked a line on my Isotherm fridge while moving it to install some trim. The repair guy can't get here before we leave for*our*summer cruise*Thursday. I have a small 110 volt reefer that draws 168 watts. I think my 400 watt inverter will start and run it. My*house bank is 430 amps*so I am O.K. there. Comments? Suggestions?


37 Sedan
"I have a small 110 volt reefer that draws 168 watts. I think my 400 watt inverter will start and run it. My house bank is 430 amps so I am O.K. there."

OK means just what? Overnight at the hook?

With the usual wiring and inverter in efficiencies 168W will frequently cost 16.8 AMPS of 12V .

Your 430A bank can have half 215Amps used , if the 430A was at the "20 hour rate".

The only questions left is ON time , how many min an hour does the fridge run?

If its the usual crap house unit the insulation will be minor , so figure 50% on time .

You MUST switch off the insulation heaters (the no outside condensation feature) if installed.

DO the math and see if it all works for you.

With a std car style Volt regulator it will take 6+ hours of running to get the batt set ready for the next use.

The 3 or 4 stage V reg , WITH A TEMP SENSOR, will cut this down a bit.
Thanks FF. Don't really know how much it runs. Thought I would hook it up today and moniter it on the Link 2000 once it cools down. The 430 amps is at 20 hours.*We have a large alternator with a three stage regulator. Almost always on the hook. If the draw is too much we will go to the coolers and haul ice.

37' Sedan
Keep in mind that you can only reasonably use 50% of your battery capacity. At 430 AH on a bank you have 215 usable AH to safely discharge and recharge your batteries before you shorten their life considerably, especially older batteries. OTOH, if you are plugged into the dock and running a charger you will be fine IF the charger will keep up with the usage. You also need to determine the START UP for the fridge as to whether the inverter can handle it. The good news is you can try it and even if it does not work it can't hurt the fridge or the inverter. Chuck

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