Paradise, Whitney and Enterprise
Three towns next to Henderson that belong to no city. For HVAC work, that changes who issues the permit.
Run by the county
Paradise, Whitney and Enterprise are unincorporated towns. Each has a Town Advisory Board whose members advise the Clark County Commission on services to the area, and the Commission itself governs (Clark County TAB and CAC information).
Names can mislead here. Whitney Ranch, with its recreation center, is a Henderson neighborhood (Henderson fact sheet); the town of Whitney is unincorporated county land, outside Henderson.

County permits for a changeout
Clark County's Department of Building and Fire Prevention issues residential A/C and furnace replacements under 5 tons as simple online permits through its Citizen Access Portal, without plan review. Each permit covers one appliance, so replacing a condenser and a furnace on the same house means more than one permit. Equipment inside or attached to a manufactured home goes through the Nevada State Manufactured Housing Division instead (Clark County simple permits).
Same licensing rules
County or city, the contractor still needs a Nevada State Contractors Board license in the right classification. The hiring guide shows how to check it.
Where these facts come from
Referral notice
This site is a free service to assist homeowners in connecting with local service contractors. All contractors are independent and this site does not warrant or guarantee any work performed. It is the responsibility of the homeowner to verify that the hired contractor furnishes the necessary license and insurance required for the work being performed. All persons depicted in a photo or video are actors or models and not contractors listed on this site.
Talk it through with an HVAC contractor
Say what the equipment is doing and how old it is. An independent contractor who works in Henderson, Nevada takes it from there.