About this site
Coil Swap Check exists because of one question that got hard to answer in 2025: when the new outdoor unit uses A2L refrigerant, what can you keep? The answer is different for your indoor coil, your copper line set and your furnace — and it changes by manufacturer, sometimes by model.
Those answers already exist. They are in manufacturer FAQs, service bulletins and installation manuals, mostly as PDFs that no homeowner will ever find. This site reads them, states what they say in plain English, and links back to the document with the date it was read.
Who publishes it
Coil Swap Check is published without a byline. That is deliberate, and it is worth being straight about what it costs you: you cannot look up who wrote this, so you have no reason to take a word of it on trust.
So don't. Every factual sentence here names the document it came from, the section or printed page it is on, and the date somebody opened it. That is what you should be checking, and you can check all of it without knowing who did the reading. If a page tells you what Carrier says, it links the Carrier document — go and read the sentence yourself. A site that cites nothing is worth nothing whoever signs it.
What this site is not: not a contractor, not a manufacturer, not affiliated with any brand, and not paid by one to say anything. It carries advertising and, where they exist, affiliate links, which are marked as such. No manufacturer has any say in a verdict on this site, and no verdict here has ever been changed because of one.
The rules this site follows
- Every answer names its source. If a page says a manufacturer allows something, the document is linked and dated.
- A conclusion is labelled as a conclusion. "Carrier states" and "this follows from Carrier's rule" are different claims, and the page says which one it is making.
- When the manufacturer is silent, the page says so. There is no house opinion filling the gap, because a wrong "you can keep it" costs somebody a new system.
- Nothing here is an approval. The licensed contractor who signs your installation decides what goes in your house.
Corrections
Manufacturers revise these documents without notice, and this site has already found and fixed its own mistakes — model numbers transcribed from the wrong table, a federal rule read through a distributor's summary of it. Every claim has been re-read against the document it cites, and the ones that did not survive were changed.
If a page is out of date or contradicts a document you have, send it. Corrections take priority over new pages, and the page will say the date it was last checked when it changes.
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.