What replaced the Carrier 24SCA4?
Checked against 24SCA4 Comfort Series Single-Stage Air Conditioner with Puron Refrigerant — Product Data, September 2026.
The 24SCA4 is an R-410A air conditioner — Carrier's Comfort tier, single-stage, sold in the northern efficiency region only. R-410A equipment stopped being manufactured after 31 December 2024, so there is no new one of these to buy — but that does not mean your only option is a whole new system.
The model Carrier points you at
Is this your unit? 24SCA4 is a family. The data
plate carries one of these numbers: 24SCA418N003 , 24SCA424N003 , 24SCA430N003 , 24SCA436N003 , 24SCA442N003 , 24SCA448N003 , 24SCA460N003 .
The copper you already have
What the 24SCA4 was installed with, size by size. The last two columns are what the 26SCA4 needs at the same capacity, so you can see before the quote arrives whether your line set carries over.
| Model | Capacity | Liquid line OD | Suction line OD | 26SCA4 liquid | 26SCA4 suction |
|---|---|---|---|---|---|
24SCA418 | 1.5 ton | 3/8" | 3/4" | 3/8" (same) | 5/8" (smaller) |
24SCA424 | 2 ton | 3/8" | 3/4" | 3/8" (same) | 3/4" (same) |
24SCA430 | 2.5 ton | 3/8" | 3/4" | 3/8" (same) | 3/4" (same) |
24SCA436 | 3 ton | 3/8" | 7/8" | 3/8" (same) | 7/8" (same) |
24SCA442 | 3.5 ton | 3/8" | 7/8" | 3/8" (same) | 7/8" (same) |
24SCA448 | 4 ton | 3/8" | 7/8" | 3/8" (same) | 7/8" (same) |
24SCA460 | 5 ton | 3/8" | 1-1/8" | 3/8" (same) | 1-1/8" (same) |
Whether your indoor coil, your copper and your furnace can stay is a Carrier rule rather than a rule about this model: the Carrier rules page states all three, with the documents behind them.
A like-for-like R-410A outdoor unit, labelled "For Service Only", is still a legal option in most states and keeps your existing coil — the phase-out guide sets out when that route closes .
How Carrier listed the 24SCA4
| Refrigerant | R-410A |
|---|---|
| Tier | Comfort |
| Compressor | single-stage |
| Region | Northern efficiency region only |
| Coastal option | Not listed |
What the documents say about this model
ManufacturerThe condenser coil in this family does not grow with the unit. Face area runs 8.4, 9.8, 17.1, 12.9, 23.6, 15.0 and 19.3 square feet from 1.5 through 5 tons, and the circuit count jumps the same way: 3, 5, 4, 5, 7, 6, 9. The 3.5 ton carries the largest coil in the range and the 4 ton above it carries one a third smaller. Cabinet size on the pad says nothing about what is inside it.
ManufacturerEvery size in this family starts at 13.4 SEER2, but the best it can reach depends on how big it is: 16.0 at 1.5 through 2.5 tons, 15.0 at 3 tons, 15.5 at 3.5, 15.2 at 4, and 14.0 at 5. The largest unit has the lowest ceiling of the range, so a system sized up for comfort is also a system that cannot be matched as efficiently.
Where the mapping comes from
DistributorCarrier Enterprise's 2025 equipment transition guide lists the 24SCA4 as an R-410A Comfort-tier air conditioner: a single-stage unit, sold for the northern efficiency region only. No coastal option is listed. The guide's Puron Advance column for this row is 26SCA4.
Read next
- Check your own swap against the 26SCA4 Your coil and your line diameters, against what Carrier publishes for the unit you are being quoted.
- The Carrier rules, with sources All three answers for the range, and every document behind them.
This is a starting point, not an approval. Everything here is read from published manufacturer documents and dated, but only the licensed contractor who signs your installation can approve a specific system for your home and your local code. Take the citations on this page to them and ask.