Is 13.3 Volts or 13.6 Volts the defacto voltage after charging and then immediately loaded LiFePO4 battery (12.8 V 280 AH)

[Brucey]

And

And I know that I may sound facetious, but I truly do wonder about all this. My INITIAL question to this entire problem is that why did everything run for over a week, out of the box brand new everything, never needing to do any charging, yet now I have to run a charger every single night just to keep the inverter from powering off from lack of voltage in the middle of the night!!!! And the sunny all days haven't changed (although today we actually have some marine layer and clouds - unusual). You see, all these questions about a refrigerator, or anything else I have, are simple common everyday every home things! And they just didn't evolve into something else between week one and now afterward. There is nothing I can figure out that answers this and why I'm asking all you experts.

That 280Ah battery contains around 3.5kWh of power.

They usually ship at around 40-50% charge.

So when you hooked things up initially, there was say 1.75kWh of charge already in the battery. With the small amount of solar charging you have that eventually dwindled down to nothing and you were left with just your solar input or AC charging. Possibly what happened

Also what voltage is that charger set to?

 

[Brucey]

Let's get rid of those alligator clips and terminate with lugs.

 

[time2roll]

And

And I know that I may sound facetious, but I truly do wonder about all this. My INITIAL question to this entire problem is that why did everything run for over a week, out of the box brand new everything, never needing to do any charging, yet now I have to run a charger every single night just to keep the inverter from powering off from lack of voltage in the middle of the night!!!! And the sunny all days haven't changed (although today we actually have some marine layer and clouds - unusual). You see, all these questions about a refrigerator, or anything else I have, are simple common everyday every home things! And they just didn't evolve into something else between week one and now afterward. There is nothing I can figure out that answers this and why I'm asking all you experts.

This would seem to indicate increased usage from that initial week.

I missed how large the inverter is but if the draw is generally less than 15 amp I recommend a Kill-A-Watt meter to track power consumption.

https://www.amazon.com/P3-P4400-Electricity-Usage-Monitor/dp/B00009MDBU

 

[Ellcon123]

It's just numbers and yours aren't working out. The energy input from solar needs to be larger than your loads. If it's not, then every day your stored energy will reduce. You need to do an energy audit to understand your requirements. What we think and what is reality are often two different things. As already mentioned, a power meter on the inverter, or individual devices, will tell you your daily consumption. You then need to figure how to meet this.

 

[Mattb4]

A refrigerator, the same thing probably most homes on the planet have (less I suppose homes in the middle of Africa).

A refrigerator pumps heat from inside to the outside. It use a refrigerant (gas most often) and it cycles it through a compressor and a stage where it can expand. As gas goes from one state (liquid to gas) it either gives up heat or picks it up. So when you say you are not running any pumps or compressors it is incorrect.

You keep repeating the same thing and not following any advice. I don't think I can be of any help.

 

[mikefitz]

When you calculate the load on the battery, it's significant. The refrigerator power need will be at least 1000 watts per day per unit, possibility nearer 2000 watt hours per unit. The fridge/s will consume power overnight, 30 to 50% duty cycle, disregarding other loads, it's possible a fully charged battery will not keep up with fridge demand.
800 watts of panels, at best, will yield 4000 watt hours over the day if the controller is setup in an optimum state.
The miscellaneous power consumption adds up, router 20 watts, computers 90 watts, TV 30 watts, inverter overhead 40 watts (estimate), total 180 watts, over a day that's in excess of 4000 watt hours.
When the power available is compared to power use, it seems there is not enough battery and/or solar.
The apparent sucess in the early use, may have been operating on a small margin of surplus power. Temperature increases may account for the change in performance.