We are running a full new construction HVAC installation out in West Fort Pierce for Cole Construction Services, and the house is at rough-in right now. That is the stage where everything we do is still visible, and it is the last chance anyone gets to see it before the drywall goes up and hides it for the next thirty years.
So this seemed like a good time to open the job up and walk through what actually goes into a new construction system, what separates a careful install from a fast one, and what a homeowner or builder should be looking for when the ductwork is still hanging in the open.
Table of Contents
What rough-in actually is
Rough-in is the phase after the block is up and the roof is dried in, but before insulation and drywall. For HVAC, it is the big one. The air handler location gets set, the supply and return trunk lines go in, every branch run is pulled to its register location, the refrigerant line set and condensate drain get routed, and the low voltage wiring for the thermostat is run.
After rough-in, most of that is sealed inside walls and ceilings. If a duct is crushed behind a truss, if a joint was never properly sealed, if a run is longer and more twisted than it needed to be, nobody finds out at inspection. They find out three summers later when one bedroom never gets cold and the power bill does not make sense.
That is why we treat rough-in as the part of the job worth photographing.
The system going into this home
This home is getting a 4 ton Lennox Elite heat pump system, matched and certified as a set:
- EL16KP1-048 Lennox Elite heat pump condensing unit
- CBK47UHET-048 matching air handler
- ECB47-8CB 8 kW electric heat kit
- 48,000 BTU capacity at 15.2 SEER2
- AHRI certified reference number 215756528
A heat pump is the right call for this climate. It moves heat rather than burning fuel to make it, which means it handles both sides of a Treasure Coast year: the nine months of cooling that actually matter here, and the handful of genuinely cold mornings in January. The 8 kW electric heat kit is backup for the coldest stretches, not the primary heat source. As a Lennox Premier Dealer, we install a lot of these, and the Elite line is a sensible middle of the road choice for a house this size.
What that AHRI number on your proposal means
That AHRI number is worth understanding, because most homeowners scroll right past it.
Air conditioners and heat pumps are rated as a matched system, not as individual boxes. The published efficiency only holds if the outdoor unit, the indoor coil, and the air handler are the exact combination that was tested together. Put a high efficiency condenser on a mismatched coil and the rated number becomes fiction. The system will run, but not at the efficiency on the sticker, and often not for as long as it should.
The AHRI reference number is the proof that the combination was certified as a set. You can look any number up yourself in the AHRI Directory of Certified Product Performance and see the tested ratings for that exact match.
If a proposal for a new system does not list an AHRI number, ask for it. A contractor who is matching equipment properly will have it. One who is not may not want you looking.
Ductwork is where installs are won and lost
Equipment gets all the attention. Ductwork decides how the house actually feels.
You can put a perfectly sized, perfectly matched system in a home and still end up with a back bedroom that runs five degrees warm, because the duct serving it got pinched behind a truss or the return was undersized. The equipment is not the problem in most uncomfortable houses. The distribution is.
On this job that means a few things we are deliberate about:
- No crushed or crimped runs. Flex duct that is kinked, compressed against framing, or pulled around a tight corner loses airflow at that exact spot, permanently. We route around obstructions instead of forcing duct through them.
- Locations thought through before anything is hung. Where the air handler sits, how the trunk is laid out, where each branch takes off. Getting that right on paper first is what keeps runs short and straight.
- Proper support. Duct that sags between hangers develops low spots that restrict flow and collect condensate.
- Clean work. If the rough-in looks organized, it usually is. Sloppy duct is a reliable signal of what else got rushed.
Mastic, and why we do not rely on tape
Duct sealing is the single easiest corner to cut on a new construction job, and the easiest one to hide.
Foil tape goes on fast. It also fails. Adhesive gives up over years of temperature swings and attic humidity, and once a taped joint lets go, you are cooling the space between your ceiling and your roof.
We seal with mastic, applied thoroughly at every connection. It is slower, it is messier, and it is the right way to do it. Mastic is a brushed on sealant that cures into the joint and stays put for the life of the duct. Every take off, every boot, every plenum connection gets it.
Leaky ducts are not a small problem. Air that escapes into an attic before it reaches a room is air you paid to cool, and duct leakage is one of the most common reasons an efficient system produces a disappointing power bill. ENERGY STAR has a good plain English breakdown of duct sealing and why it matters if you want to read further.
Sealing correctly at rough-in costs a few extra hours. Fixing it later, after drywall and insulation, costs far more than that.
The steps a rushed install skips
Once the system is set, there is a sequence at startup that separates a professional installation from a fast one. None of it is visible to a homeowner, which is exactly why it gets skipped.
- Pressure test the refrigerant circuit before any refrigerant goes in, to prove there are no leaks in the line set or connections.
- Evacuate the system with a vacuum pump to pull out air and moisture. Moisture left in a sealed refrigerant circuit turns acidic and eats the compressor from the inside. This step takes time, and rushing it is invisible until the system fails early.
- Charge to manufacturer specification, by weight and by measurement, not by feel.
- Verify operation at startup: airflow, refrigerant pressures, temperature split across the coil, and the whole system running as designed.
A system that was never properly evacuated will still blow cold air on day one. The homeowner has no way of knowing. That is the point.
Your 10 year parts warranty has a catch
Here is the one that costs real people real money, and almost nobody mentions it at the sale.
This system carries a 10 year parts warranty, and a 1 year labor warranty from us. But the 10 year parts coverage is only valid if the equipment is registered to the homeowner, usually within a set window after installation. If nobody registers it, the manufacturer typically falls back to a much shorter base warranty.
We handle registration, and we tell customers about it, because finding out in year six that your compressor is not covered is a genuinely bad day. If you already own a system and have no idea whether it was ever registered, that is worth checking now rather than later.
It is also worth knowing that our Florida 252 license lets us process eligible manufacturer warranty claims even on equipment we did not install, which comes up more often than you would think when a builder’s original contractor is no longer around. You can read more about how coverage works on our warranty page.
Building out in West Fort Pierce
This part of St. Lucie County is not suburbia. ZIP 34945 covers roughly 218 square miles west of Fort Pierce with only about 6,300 residents in it, which works out to somewhere near 29 people per square mile. It is genuinely rural, and that changes the job.
Lots are large and homes are spread out. Runs tend to be longer, layouts are more spread out than a tract home, and attic conditions in an open, sun exposed build can be brutal by mid afternoon. It is also far enough west that plenty of contractors simply will not drive out there, which is a real problem for a homeowner who needs service on a Saturday in August.
We work across Fort Pierce and out through this western corridor regularly. If you are building or buying out here, ask any contractor you are considering whether they actually service the area, not just whether they will take the install.
Planning a new build on the Treasure Coast
Just about the whole crew has been out on this one at some point: Nathan, Dalton, Bo, Rodrigo, Matthew, and Scotty. That is how most of our new construction work goes. It is not a one technician job, and the handoffs between rough-in, trim, and startup are where the details either carry through or get lost.
Thank you to Cole Construction Services for bringing us on. Working with a builder who cares about how the mechanical work gets done makes the whole thing easier, and it shows up in the finished house.
If you are a builder on the Treasure Coast looking for an HVAC contractor who will do the ductwork properly the first time, or a homeowner planning a build and trying to figure out what to ask for, we are glad to talk it through. Our AC installation guide covers sizing, efficiency, and what belongs in a proposal, and a free estimate costs you nothing but the conversation. For an existing home rather than a new build, our repair or replace guide is the better starting point.
You can also see an earlier look at our West Fort Pierce new construction rough-in work, or schedule service if you need us out.
Comments are closed