Any ideas? Gonna be a hot weekend - don't think I'll pay w/e call rates.
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Well I got a call back from the friendly service folks and they said $150/hr

The hum seemed to be coming from either the compressor or this thing on the side of it (little black box)

Then I wondered about the scum on the frame under this thing - probably normal but don't look right..

The digital thermostat looks normal (except for the current temp reading). I put fresh batteries in it just in case. The inside gas furnace and the a/c is 6 years old (still looking for the paperwork). For those more technical the inside unit model is G24M3/4 - 10A - 11 and the outside unit is HS26-042-2P. I get two alternating green blinks on the inside unit. Blower runs no matter if thermostat fan switch is in the "on" or "auto" position. How much is a capacitor for one of these things? Steve, are you fishing today? Where's AJ? The sun's getting higher - help! Thanks