We have two Lennox 13 seer a/c units that are a little over a year old. Last year we had an issue where the upstairs unit wasn't cooling properly when it became relatively hot outside. We called and both units were a couple of pound low! We didn't realize the lower unit was low as it seemed to cool ok. Before we moved into the house one of the units had to be filled(it's still not clear which one). My question is I've noticed the upstairs unit has water pouring out of the condenstation line. Much more than the lower unit. The humidity is around 43 percent both upstairs and downstairs so they are the same. Is this a sign that it's getting low on freon or is it just because the upstairs unit is larger?