What replaced the Carrier 25SCA5?
Checked against 25SCA5 Comfort Series Single-Stage Heat Pump with Puron Refrigerant — Product Data, September 2026.
The 25SCA5 is an R-410A heat pump — Carrier's Comfort tier, single-stage, with a coastal option. 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? 25SCA5 is a family. The data
plate carries one of these numbers: 25SCA518A003 , 25SCA524A003 , 25SCA530A003 , 25SCA536A003 , 25SCA542A003 , 25SCA548A003 , 25SCA560A003 .
The copper you already have
What the 25SCA5 was installed with, size by size. The last two columns are what the 27SCA5 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 | 27SCA5 liquid | 27SCA5 suction |
|---|---|---|---|---|---|
25SCA518 | 1.5 ton | 3/8" | 5/8" | 3/8" (same) | 5/8" (same) |
25SCA524 | 2 ton | 3/8" | 5/8" | 3/8" (same) | 5/8" (same) |
25SCA530 | 2.5 ton | 3/8" | 3/4" | 3/8" (same) | 3/4" (same) |
25SCA536 | 3 ton | 3/8" | 3/4" | 3/8" (same) | 3/4" (same) |
25SCA542 | 3.5 ton | 3/8" | 7/8" | 3/8" (same) | 7/8" (same) |
25SCA548 | 4 ton | 3/8" | 7/8" | 3/8" (same) | 7/8" (same) |
25SCA560 | 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, labeled "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 25SCA5
| Refrigerant | R-410A |
|---|---|
| Tier | Comfort |
| Compressor | single-stage |
| Region | All regions |
| Coastal option | Offered |
What the documents say about this model
ManufacturerCarrier's product data for the 25SCA5 rates every capacity in the family on a 3/8 inch liquid line, for tube lengths from 0 to 80 feet. The vapor line changes with capacity: 5/8 inch at 1.5 and 2 tons, 3/4 inch at 2.5 and 3 tons, 7/8 inch at 3.5 and 4 tons, and 1-1/8 inch at 5 tons.
ManufacturerCarrier allows the 25SCA5 up to 250 feet of total equivalent line length, with the outdoor unit up to 200 feet above the indoor unit or up to 80 feet below it.
ManufacturerBeing a heat pump, the 25SCA5 also carries an outdoor heating piston sized per capacity — number 42 at 1.5 ton rising to 76 at 5 ton — and a factory charge that runs from 5.9 to 13.7 pounds across the family. An air conditioner of the same tier has neither figure, and both are set by the capacity rather than chosen at installation.
ManufacturerOn the 3/8 inch liquid line this family is rated for, Carrier treats the system as long line — needing extra accessories — beyond 80 feet on the same level, and beyond 20 feet of vertical separation when the outdoor unit sits below the indoor unit.
ManufacturerIts cooling capacity loss table has two columns for the same distance, headed 80 and 80+, and every row of the sheet prints the identical figure in both. The pair is not a jump in loss at eighty feet; it is where the job stops being a standard application and becomes a long-line one needing accessories. The number does not change at that point. What the installer has to buy does.
Where the mapping comes from
DistributorCarrier Enterprise's 2025 equipment transition guide lists the 25SCA5 as an R-410A Comfort-tier heat pump: a single-stage unit, sold for all regions. A coastal option was offered. The guide's Puron Advance column for this row is 27SCA5.
Read next
- Check your own swap against the 27SCA5 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.