Home air conditioner ?

Water is condensate so the A/C is working. If the condensate line is blocked it may trip a safety valve which will effect A/C. I  just fixed a blocked drain line and I had lots of water on the floor and it drained under the wall and out the garage. It did not affect cooling as the water made it to the floor drain before over-flow. Yours may be clogging in the drip pan. Next time it kicks on watch it to see where the water is coming from. U tube has lots of videos on this for different types.

The AC is also like a giant dehumidifier, it's going to sweat, it's going to remove moisture from the air, you are going to have water, just ensure your drain lines are not clogged.  Pressure depends on ambient temp, temp of conditioned air, cleanliness of coils and filter, size of the unit and such. You want supply and return temps, you are looking for 15 to 20, less then that indicates an issue and it may not be simply the charge.

The pressures  on the unit are test pressures. If it is R-22 should be between 65-75 depending on outside temperature an inside temperature.   The best way to charge a unit is super heat or sub cooling depending on the refrigerant metering device. 

Depending on how low it is you might be better off to have the 22 recovered an replaced with a 22 drop in refrigerant  mo99, R421a, r407c there cheaper refrigerant.

An hey if they try to upsale you which they should R22 equipment is very old now.  If you lived in my state it be atleast 17 years old which is 2 to 9 years past life expectancy dependingon the brand.  Which is based on compressor.  But if you don't want to replace it geow a backbone an tell them no.

Trust me they'll be more than happy to charge you a outrageous amount for R-22. 

go with the pressure figure from the compressor label.  and call around to find a technician who will simply add R-22 if that's what is needed.  A thorough technician will use a leak detector to isolate the leak and then you'll know what you're dealing with.  OR [door number 2], you can buy the gauge and hoses system online, plus the R-22 you maybe need and refill the refrigerant yourself.  While that's for sure cheaper in the medium term, it won't help you find the cause of low refrigerant [the leak] -- assuming that is the actual problem.  I had a slow leak in my indoor unit for four or five years before I replaced the whole thing -- added one pound of R-22 every August at nominal cost [like $20] because I'd bought the gauges and hoses assembly and learned how to use them [see youtube videos online].  didn't replace the system until I had to add more R-22 every three months or so instead of once a year.  [Btw: my new system is SEER 14 and more efficient than the old one -- the lower annual operating cost doesn't offset the up front $7k cost [2.5 ton unit] and it does help a little.  -- grampa -- I'm in steamy Florida, it was 95 here yesterday.

ensure that the condensate is flowing out properly and remove any kinks on the condensate line.

clean the filter of indoor unit after every 2-3 weeks.

close the doors and windows of the room having AC unit and replace any worn-out thermal insulation on the cold line.