Subject: Re: Zweig article/30-year Returns
So far, I've been able to do all my own HVAC repairs. If I have to bring a contractor to the house, I regard it as a failure.

Then you haven't had any serious AC problems.

The most common failure is when the capacitor goes bad. Trivially easy to fix. Order a capacitor from Amazon (~$25-$35) so you have it on hand. HVAC company will charge $100 for the part and $150 for the service call.

Small freon leak, you can't even find it without special equipment. Which a DIYer won't have.

Bad blower motor, you can replace yourself. But most people won't be able to DIY.

Bad compressor or bad exhaust fan on the outdoor unit -- maybe you can DIY replace the fan, but the compressor or control board you cannot.

We had a nearby lightning strike take out our heat pump. I tried everything then called the HVAC service. Turned out the surge scramble the brains of the thermostat.