The distribution/wholesale network for residential HVAC is rather convoluted.

While I do like authorized dealers(documented and verified) because I do believe this gives the homeowner a small measure of protection, this should not be a deal breaker when selecting a dealer.

Two thoughts

You need to understand and verify that new install has been properly registered for the manufacturer warranty.

And you will get no manufacturer warranty purchasing HVAC over the Internet.

IMO

Thanks. Researching online I have seen that if the system isn't registered somewhat quickly the warranty period is greatly reduced. And the internet can be great for buying some things, but certainly not this.

I generally like the dealer in question... he's spent a good deal of time speaking with me, answering questions and making suggestions, and his pricing is competitive (but not cheapest). It was actually my idea to get a Trane bid from him, after hearing that there can be issues regarding Carrier parts for service. Plus, Carrier seems to be more expensive.

Parts issues seem to be less about the brand and more about your location and the quality of that whole seller support. Some areas are quite good about a brand and other areas quite poor about same brand. Of course many of the parts are exactly the same from one brand of HVAC to another brand which simplifies many parts issues.

I just don't like the broad brush you seem to be using on this parts issues.

IMO

Would the non-dealer installer be able to provide annual service or repairs? If he did, would warranty be affected?

Just checking everything before pulling the trigger...

It's done everyday, not an issue.

IMO