A new central air conditioner is a big enough expense that most Treasure Coast homeowners want to know exactly what to expect before the install van rolls in. The decision to replace usually happens days or weeks earlier, often after a tough repair call or a quote that finally tips the math. What happens on the day itself is its own thing, and a lot of the anxiety around it comes from not knowing the order of operations.
This walkthrough covers a typical Honest Air, Inc. central A/C replacement on a single-family home in Stuart, Palm City, Port St. Lucie, Jensen Beach, or one of the surrounding Treasure Coast neighborhoods. Equipment placement, the age of the existing system, whether the air handler lives in the attic or the garage, and the weather all shift the timeline. The basic flow stays the same.
What Happens Before Replacement Day Begins?
The bulk of the work that protects a smooth install day takes place before any equipment is unboxed. The replacement quote drives the schedule, the equipment order, and the permit, and the more accurate the upfront walkthrough is, the fewer surprises come on the install date. By the time the truck pulls into the driveway, the homeowner should already know the brand and tonnage of the new system, the cost of the install, the timing of the inspection, and what is and is not included in the price.
The Walkthrough and Quote
The first visit is the in-home walkthrough. A certified technician measures the conditioned square footage, looks at the existing condenser pad and air handler, checks ductwork condition, and confirms the tonnage the home actually needs. That last step is where some replacement quotes go wrong. If a contractor sizes the new system off the old unit instead of the home, the new system can end up oversized or undersized for the load. Verifying that tonnage matches the home, not the old equipment, is the difference between a system that runs efficiently for 12 years and one that short-cycles from the day it is installed.
The walkthrough also includes a duct inspection, a load check on the existing electrical disconnect, and a look at the line set from the condenser to the air handler. If the homeowner is replacing the system after years of repair calls, the walkthrough is the place where the repair-versus-replace math from the prior visit finally turns into a written quote.
Permits and Scheduling
Martin, St. Lucie, and Palm Beach counties all require a mechanical permit on a central A/C replacement. The contractor pulls the permit in the homeowner’s name before the install date, schedules the county inspection for after the job, and orders the equipment so it lands at the warehouse the day before. A clean prep means the truck shows up loaded, the permit is already filed, and the inspection is on the calendar. Most install dates land four to ten business days from the signed quote, which is the window the permit office and the equipment distributor both work inside.
How Long Does an A/C Replacement Actually Take?
A standard same-platform central A/C replacement on the Treasure Coast runs six to eight hours of on-site work for a two-person crew. That window includes removing the old condenser and air handler, setting the new equipment, brazing the line set, pressure-testing and pulling a vacuum on the refrigerant lines, wiring the new thermostat, and running through the startup checklist before the crew leaves. Most jobs that begin around 8:00 in the morning finish before mid-afternoon. The breaker for the existing condenser is shut off at the panel within the first 15 minutes, so the home goes warm for most of the day.
When the Job Takes Longer Than One Day
A few things push the install past a single day. Replacing ductwork alongside the equipment turns a one-day job into two. Switching platforms (for example, moving the air handler from the garage into a new attic location, or upsizing the line set) adds time for sheet-metal work and supply-plenum changes. Adding a return, replacing a heavily corroded condenser pad, or coordinating with an electrician for a new disconnect or whip can also stretch the schedule. The recent R-454B refrigerant change has not added meaningful on-site install time, but it has changed how the lines are pressure-tested and charged, which is worth knowing if a quote looks different from one a neighbor got a year or two ago.
What Do the Technicians Do During the Install?
The actual install moves in two halves: pulling out the old system, then setting and starting the new one. A typical crew is a lead installer and an assistant. Doors stay propped, drop cloths cover floors from the air-handler closet to the exterior pad, and the breaker for the existing condenser is shut off at the panel before anyone touches refrigerant. The refrigerant in the old system has value and is also regulated, so the recovery step happens first, not last.
Removing the Old System
The crew starts by recovering the refrigerant from the old system into a sealed recovery tank, which is required under federal EPA rules. The condenser is disconnected from the line set and the electrical disconnect, lifted off the pad, and loaded onto the truck. Inside, the air handler is unwired from the thermostat and the emergency cutoff, the condensate drain line is cut, and the unit is pulled out of the closet or attic. The old line set is inspected. On a same-platform replacement with copper that is in good condition and properly sized, the existing line set can usually stay in place. On a system that has been leaking, was sized wrong from the start, or shows pinhole corrosion from Treasure Coast salt air, the line set comes out too.
Setting and Connecting the New System
The new condenser is set on the pad, leveled, and anchored. The new air handler goes back into the closet or attic and is sealed to the existing supply plenum, or to a new plenum if the platform has changed. The crew brazes the line set with nitrogen flowing through the copper so the inside of the line stays clean during the heat of the joint. The condensate line and the float switch are reconnected so the system cannot run with a backed-up drain. The new thermostat is wired in, and the homeowner’s existing schedule is brought across when the platform allows it.
The lines are then pressure-tested with nitrogen at the manufacturer’s spec to confirm there are no leaks at any joint. After the pressure test holds, the crew pulls a deep vacuum on the line set with a micron gauge to remove every trace of air and moisture. Only then is the refrigerant released into the system from the factory-charged condenser. Skipping the vacuum step is one of the most common ways a brand-new system ends up failing inside the first cooling season, which is why it is a logged step on the install sheet rather than a judgment call.
What Happens After the New System Is Running?
Startup is the part that separates a clean install from a callback. Once the system is charged, the crew runs the air conditioner through a full commissioning cycle: thermostat settings, blower speed, supply and return temperature split, subcooling and superheat, and amp draw on the condenser. Every reading gets logged on the install sheet. If any number is outside the manufacturer’s range, it gets corrected before the truck leaves the driveway. A system that reads in range at startup almost always stays in range; a system that is left a little off at startup is the system that calls in mid-July.
Startup, Settings, and Warranty Registration
After the readings clear, the lead walks the homeowner through the new thermostat, the indoor and outdoor disconnects, the air filter access, the condensate access, and the startup paperwork. The serial numbers go onto the registration paperwork the same day so the parts warranty starts on time. The county inspection is scheduled within the window the permit office requires, and the inspector confirms that the equipment, the disconnects, the pad, and the condensate plumbing all meet code before the permit closes.
The first month after a new install is usually when small comfort issues show up: a register that needs balancing, a return that pulls harder than expected, a thermostat schedule that was set for the old system. A scheduled follow-up visit handles those and rolls the system into an ongoing maintenance plan that keeps the manufacturer parts warranty intact and catches small drift before it turns into a service call. The replacement is the big spend; the maintenance is what protects it.
Frequently Asked Questions
How long does an A/C replacement take?
A standard same-platform central A/C replacement runs six to eight hours of on-site work for a two-person crew. Same-day completion is normal when the existing line set is in good shape and the duct system is staying. Replacing ductwork, switching platforms, or coordinating with an electrician for a new disconnect can push the job into a second day. The crew will give a realistic window on the morning of the install once the old system is open and the condition of the line set is confirmed.
Do I need to be home during the install?
An adult should be on the property to grant access, sign the permit paperwork, and walk through the new system at the end. The crew does not need a homeowner watching the install itself. Most homeowners use the day to work in another part of the house, run errands, or stay with the dog. Plan for the air conditioning to be off for several hours mid-install, and plan to be available for the closing walkthrough so the thermostat and warranty paperwork are handed over directly.
Do I need a permit for an A/C replacement in Florida?
Yes. Martin, St. Lucie, and Palm Beach counties all require a mechanical permit on a central A/C replacement, and the inspection that closes the permit is part of the job. A contractor that offers to skip the permit to save a few hundred dollars is creating a problem for the future buyer of the home and for any warranty claim that depends on a permitted install. A pulled permit and a passed inspection are the only paper trail that proves the system was installed to code.
What happens to my old A/C unit?
The refrigerant is recovered into a sealed tank under federal EPA rules. The condenser, the air handler, and any removed line set ride out on the install truck. The copper and the steel are recycled. Homeowners do not pay extra for old equipment removal on a standard Honest Air replacement; it is part of the install price quoted on the contract. The recovery tank goes back to the shop for proper handling.
Should I replace my ductwork at the same time?
Replace ductwork at the same time when the existing ducts are undersized for the new tonnage, when they show visible mold or moisture damage, when sections are crushed or disconnected, or when the home has cold rooms and hot rooms that point to a duct-design problem. Otherwise, the existing ducts can usually stay and a duct-sealing pass can recover most of the lost airflow at a lower cost. The walkthrough is the visit where that call is made, not the install day.
Can I install a new A/C system myself?
No. Florida law requires a certified A/C contractor to pull the permit, braze the refrigerant lines, and complete the startup on a central A/C system. Unpermitted homeowner installs void manufacturer warranties, fail the eventual inspection when the home sells, and create real safety risk on both the electrical and the refrigerant side. The cost of a corrective install after a failed do-it-yourself attempt is usually higher than the original quote would have been.
How soon should I expect to see lower energy bills?
The first full billing cycle after the install is the cleanest comparison, and the size of the drop depends on how inefficient the prior system had become. A 13-year-old system replaced with a current high-efficiency unit typically shows a measurable monthly cost drop right away during peak Florida summer use. The savings curve flattens by year three as electric rates and household habits shift, but a properly sized, properly commissioned replacement keeps that gap stable across the system’s lifetime.
Ready to Schedule a Replacement Walkthrough?
A clean replacement day is the result of a clean walkthrough, an accurate tonnage match, a pulled permit, and a crew that runs the startup checklist instead of skipping it. The work itself is mostly routine. When a central A/C installation is on the Treasure Coast calendar this season, an in-home walkthrough is the starting point. Reach out through the contact form or the Book Now page to schedule, and the visit becomes the first step in a written, permitted, inspected replacement.
