I will tell you some of my HVAC repair stories. We put an addition on that required a new, bigger furnace about 12 years ago.
I should say that the guy that put it in was sort of a friend, but came recommended by several other friends. It was installed in the fall, and the next winter season it would not light off. It was about a month into the season I called him and he replaced the glow stick and said it is ceramic, and maybe it cracked in installation.
The next winter rolls around, a month into heating season same thing, again under warranty.
Third year rolls around again a month into the season, no heat. This time he says I will have to pay for the part, but he will install it. Charged me $100. One problem for him is I grabbed the box right away and told him I would throw it away.
By now I have had this furnace apart several times to know what it was, before I even called him about the problem. I took the box over to the supply store, to get one for the next time, because I just knew it was sooner or later going to go out when it was really needed.
The guy at the supply store says do you want that style or the better one. I asked about the better one, and he said they have had so many problems with the OE style that they have redesigned them in the aftermarket. The original was $18 and the redesigned one was $40. I bought both. The one eventually burnt out again, and I replaced it with the better one, and not had a problem since.
early this summer my furnace started vibrating. I called another referred HVAC guy. He came out and tore the furnace down. Him and his guy were here two hours or more, and they had the blower in and out several times. He finally just said, I do not know what wrong, call me when it gets worse.
About two weeks later the furnace was trying to walk across the floor. He came out and determined the center had broke out of the blower wheel. Motor, blower wheel installed was about $600.
A few weeks later the wife turned the air on and no condenser fan operation. I called the HVAC store and the part was $300. Called the furnace guy again and he stopped, it was a capacitor and he topped the charge off for $100.
Some time later this year, the outside unit just would not start. Called him and he was right here and looked at it and came to get me. There is a large tree near and a limb had fallen at some point, knocked out two window screens and tore the little wires out of the unit. Two wire nuts and a handshake he was gone. No charge.
End of the cooling season, last week of needing the AC it quits again. This time it is toast, compressor failure. He looks at the unit, says he will likely have to change the a coil also. Heads to the basement and says he will call me in a few hours.
Stps back to look at the furnace and shows me where the original guys have creating the plenum out of the a coil. Half of the house is getting air flow that is not even going through the coil. That half is the west side and upstairs. The two places that you need cooling the most.
Will have every thing replaced in the spring for $6k. The original guys did me no favors. The wife want to change up the landscaping where the outside unit sets. Knowing that we will not have AC until that area is ready for the new unit, likely moved the landscaping project to the top of the summer list of honey dos.