Delonghi Pinguino PAC L90 is flashing Lt on the display.

get it from here

This really Expensive AC quite on me. The fan works great, I hear the Compressor turn on and it still doesnt blow cold air. Should I flip out?

yes we charge freon if it leaks out, but we fix the leak first. but also it may have electrical problem only, better get it check with a technician

they all take refrigerant but there are other things like dirty filter or condensor coils that will cause the same problem

No that would be either a dirty filter/coil ir low refridgerant if it's freezing in cooling mode.

Clean/replace the filter, clean the coil and if it keeps doing it, have a technician who is EPA certified for servicing systems with refridgerant to look at it/add refridgerant.

Here you go!

http://www.manualnguide.com/download/manual-guide/delonghi-pinguino-pac210-portable-air-conditioner-owners-manual.html

It's actually "Ft", which means "Full Tank".  The instruction manual says to drain the internal safety tank through the drain hoses.
To drain the tank, open the cover on the rear of the appliance. Pull out the 2 drain hoses, take off the caps, and let all the residual water flow out.  When all the water has been drained, place the caps back on the hoses and put the hoses back inside.
It also says you need to clean the filters and let them dry thoroughly before putting them back.
This is also the procedure for "End of Season Operations."
Hope this helps!

Call 800-865-6330.  The white accordion 3M Filtrete filter is $37.95, and is NOT available on the Delonghi website.

Hoses for proper connection should have been included with your purchase. Without the hoses the set-up can not be done satisfactory. One is for fresh air supply and the other is the hot air exit hose. These are normally vented out a window. Check with the dealer where you perchased the unit from. If from a private individual contact them.

You need drain the water and then function normally.