I'm sure most of you have heard this before, But I still need to ask some questions before I make a call for service.

I have a Carrier 38TKB unit that is not keeping the house cool enough. The unit outside will run constantly, but very little cool air is coming through the registers inside. Seems to be getting less and less, over the last 2 days.

The furnace unit(Singer) has an Emerson Electro-Air filter system on the lower right side. It's clean and working.
The motor on the furnace, as best as I can describe it sounds like this ... tink-tink-tink-tink-tink.

The fins on the unit outside, are clean. The system has be running for 2 days, and will not get the house any cooler than 75-76 degrees. Before I make a call for service, is there anything else I can check ?

Thanks for any help....