Modern Fridges and freezers are hard to power safely with solar
If you want your solar system to power a modern AC powered fridge/freezer,
especially a full sized one, there are some things to know. Modern fridges
have a higher chance of containing digital components like a microprocessor.
This means the fridge NEEDS a clean AC sine wave at all times. Fridges also
have a high current surge when they turn on their compressor. This makes
devices like fridges risky to power with low quality inverters, as fridges
can make an inverter go from 0 watts to high watt output. The inverter needs
to do that while maintaining a good 120 volt AC sine wave. If the sine wave
goes to far out of spec from the 120 volt specification the fridge was
designed for, the odds skyrocket that the fridge will be damaged. Many
inverters claim to have a pure sine wave output, yet there are plenty of
videos on youtube showing how ugly the sine wave of some inverter models
create under certain condition, especially when suddenly asking the inverter
to give alot of power. Trust but verify that an inverter does what it claims
to do.
Before you buy an inverter, do some online searching for:
A waveform video on the inverter you want to buy. Make sure the
inverter can maintain a good sine wave transition from 0 to any
level of power output (with in spec). It's a good sign if you can't
find any bad video's.
See if you can find reports of people claiming the inverter killed
their fridge/freezers. If there are many bad reports the inverter
either has problems maintaining a good sine wave or fails in a very
ungraceful manner killing all the snowflake curcits attatched to it.
Avoid that inverter even if it is a killer deal.
For off grid application, we prefer dc powered fridges. But if you
need to use AC, do your research on the inverter you want to buy.