I have an older American Standard furnace and condensing unit that hasn't been keeping up with the demand over this hot summer. It's a basic unit, 11 SEER, no multi-zone, multi-speed kind of stuff.

I have some basic understanding of HVAC and refrigeration. I cleaned the condenser and all the mechanical parts seem to be functioning correctly. Filter is clean. I did measure the temperature of the air coming out of the condenser an it's only about 9-10 degrees above ambient. My gut reaction is that it is low on refrigerant but I'm not an expert.

If I bring in a pro, what should I expect him to check. Are there any other adjustments than can be made other than the refrigerant charge?

Thanks!

When was it last serviced by a pro?

The truth is there is very little the average homeowner can do as far as PM.

Call around to reputable dealer. Ask what the cost for a routine check of total system would be including the possibility of needing refrigerant added. And make no mistake, adding refrigerant without finding leak is a waste of time. The pros know what to look for. Adding dye to refrigerant can help find leak but it would involve a followup call in perhaps several weeks.

IMO
Good Luck!

We (she actually, I wasn't around) had a guy out last year who put some refrigerant in it. I'm not sure how well trained he may have been given he ignored an obviously dirty condenser.

I'm just curious what a "routine check" involves beyond putting a set of gauges on it.

Condensers do get dirty. I would be more concerned about the condition of the evap coil and blower motor Asbly. These should be checked.

IMO