R407A can be a supported alternative to R404A in some existing commercial refrigeration systems, but it is not a universal drop-in replacement. Choose between keeping R404A and converting to R407A only after checking the exact compressor, operating duty, expansion valve, controls and required protection. A cylinder comparison cannot establish whether the installed machine will preserve enough capacity or operate within its approved envelope.
For a working R404A asset, the practical question is whether a documented conversion improves the service plan enough to justify its cost and disruption. For equipment already using R407A, the question is usually how to service the approved charge correctly. Neither situation authorizes mixing the two refrigerants or changing the label before an approved conversion has been completed.
This guide addresses that specific pair in existing low- and medium-temperature refrigeration. It does not compare residential air-conditioning refrigerants or recommend an A2L conversion. Manufacturer examples identify documents to consult, rather than instructions for every machine. Technical and U.S. regulatory sources were checked on October 3, 2026; the responsible contractor must use the documents applicable to the actual equipment and location.
R404A and R407A: what changes in the comparison?
Both names identify manufactured refrigerant blends. Their formulations and pressure-temperature behavior belong to the finished product. Sharing components does not make the products interchangeable. A service team should identify the charge already in the system from the equipment record and conversion history, rather than selecting a cylinder because its color resembles one used previously.
The composition table below separates every constituent onto its own row. Percentages describe blend formulation by mass, not instructions for making a blend in the field. Use the refrigerant manufacturer's documentation and SDS for the supplied product. Differences in safety class, environmental metrics and thermodynamic behavior answer different questions; none replaces equipment approval.
| Item | R404A | R407A |
|---|---|---|
| R32 by mass | 0% | 20% |
| R125 by mass | 44% | 40% |
| R134a by mass | 4% | 40% |
| R143a by mass | 52% | 0% |
| ASHRAE safety class | A1 | A1 |
| Main comparison here | Existing approved charge | Potential approved conversion |
The ASHRAE refrigerant designations provide the classification reference. A1 describes a refrigerant classification; it does not mean an installation is free from pressure, exposure or service hazards. Nor does it establish that every A1 fluid fits the same compressor, valve or lubricant specification.
Start with the equipment identity, not the refrigerant advertisement
Record the complete condensing-unit and compressor models, including suffixes. Also identify the evaporator, expansion device and controller. A compressor family name is an incomplete approval check when the manufacturer distinguishes motor versions, production generations or application regions. Photograph readable labels and retain the relevant document revision in the job file.
Then establish what the equipment actually contains. An older R404A nameplate may coexist with a later conversion label. A handwritten service note may name a refrigerant without explaining the work performed. Resolve conflicting records before ordering service refrigerant or proposing another conversion. Uncertainty about the existing charge is a separate problem from uncertainty about the preferred candidate.
Ask the contractor to state the starting refrigerant and the intended end condition in plain language. “Convert this documented R404A circuit to approved R407A service” is reviewable. “Use an alternative refrigerant” leaves the essential choice undefined. That difference affects the bill of materials, service procedure, labeling and eventual acceptance record.
What Chemours says, and what its product page cannot approve
The current Chemours R407A product page describes R407A for low- and medium-temperature refrigeration and includes conversion of existing R404A units among its applications. That establishes a legitimate candidate to investigate. It does not establish approval for a particular installed compressor or promise unchanged performance after conversion.
Treat the product description as the opening of an engineering review. The next evidence must come from the equipment and component manufacturers. Identify the applicable refrigerant list, operating envelope, lubricant requirement and any discharge-temperature protection. Where an OEM document refers to several starting refrigerants, confirm which instructions apply to the R404A-to-R407A path.
A contractor's past success with a similar machine can help locate useful documents. It cannot substitute for them when the proposed unit differs in compressor version, evaporating temperature or protection package. Ask for the comparison on the actual asset, especially when the equipment already struggles during busy periods or unusually warm weather.
Read the theoretical capacity comparison without turning it into a promise
Chemours' July 2026 PUSH bulletin, C-11261, includes a theoretical R404A/R407A comparison in Table 2b. At its stated medium-temperature conditions, relative capacity is 1.00 for R404A and 0.89 for R407A. At its low-temperature conditions, the values are 1.00 and 0.86. Those are modeled reference results, not measured performance of your installation.
Both examples use 110°F condensing temperature and 10°F superheat and subcooling. Evaporating temperature is 20°F for the medium-temperature example and −20°F for the low-temperature example. The table also shows different discharge temperatures and coefficients of performance. Read the complete assumptions in the Chemours bulletin before comparing its numbers with another source.
| Reference condition | R404A capacity | R407A capacity |
|---|---|---|
| Modeled medium temperature | 1.00 | 0.89 |
| Modeled low temperature | 1.00 | 0.86 |
| Basis | R404A = 1.00 | Same table assumptions |
The value of this example is the question it raises: how much capacity margin does the actual machine have? Do not multiply the nameplate rating by these factors and call the result an approved selection. Obtain the compressor manufacturer's results at a common duty and with its required accessories included.
Capacity margin matters more than a broad efficiency claim
An asset with spare capacity and an asset already running near its practical limit can reach different decisions about the same refrigerant. Document the cooling requirement and the equipment's performance under a representative operating condition. A conversion should be evaluated against the load the equipment must carry, rather than against the easiest day on which it happens to operate.
Request a comparison that uses the same evaporating temperature, condensing temperature, superheat, subcooling and compressor model. If the two results come from different rating conditions, keep them separate until the discrepancy is resolved. A percentage improvement in one brochure cannot be subtracted from a percentage reduction in another to create a reliable site forecast.
Also distinguish a steady holding load from recovery after deliveries or door openings. Managers may accept satisfactory overnight temperatures while overlooking slow recovery during service. The contractor should understand which operating period constrains the business. An acceptable selection preserves the required duty within the documented equipment limits, with any uncertainty clearly stated.
Check the compressor envelope and discharge protection together
Compressor approval is more than finding R407A somewhere in a publication. The operating envelope and required accessories must cover the proposed duty. When protection depends on a particular controller, valve or injection arrangement, include that equipment in the scope and verify its presence before accepting the selection.
For example, Copeland's ZF Specter technical information concerns specified previous-generation ZF24–48K4E-TW* models and discusses model-specific injection and DTC requirements. It is evidence to check that package, not a rule that every R407A compressor needs the same protection.
Ask the contractor to identify the document, model applicability and required protection in the quotation. If the answer is merely “both fluids are A1,” the mechanical review is unfinished. A refrigerant safety class cannot answer a compressor discharge-temperature question. Similarly, an existing alarm does not prove that all manufacturer-required protective functions are installed and configured.
Temperature glide changes how the comparison is interpreted
R407A's zeotropic behavior requires attention to the pressure-temperature reference used in measurements and controls. The technician must know whether a calculation calls for dew-point or bubble-point data, and whether the equipment literature uses an average evaporating temperature for a particular rating. Comparing unlabeled temperatures can conceal a difference in reference rather than a difference in performance.
The Tecumseh retrofit guidance for positive- and medium-temperature systems illustrates dew-point use for superheat and bubble-point use for subcooling. Its application scope should remain visible. Do not extend a positive- or medium-temperature procedure into a low-temperature freezer application without the appropriate manufacturer's instructions.
In the project record, label the refrigerant and reference alongside every acceptance measurement. A screenshot that only says “saturation temperature” may leave the next technician guessing. Good labeling also prevents a copied controller setting from being treated as valid simply because its displayed number resembles the previous R404A setting.
Expansion valves need an actual conversion decision
The existing thermostatic expansion valve is part of the refrigerant selection. Identify its body, capacity designation, element or power assembly and equalization arrangement. A valve body that can physically remain installed does not prove that its existing thermostatic element provides appropriate control with R407A.
Parker Sporlan Form 5-492, revision 2 of 2017, discusses component sizing and TEV considerations when converting R404A applications to other blends. These are Sporlan guidance and application considerations, not universal instructions for every valve brand. The correct response is to review the installed device with its manufacturer.
The newer Sporlan Bulletin 210-40-4, April 2025, distinguishes refrigerant codes, valve types and replaceable elements. It also notes limits to field conversion information. Have the contractor identify the applicable selection and parts, rather than assuming an adjustment screw can compensate for every refrigerant change.
Liquid-line components and controls belong in the bill of materials
A conversion quote should identify which installed components remain suitable and which require replacement, adjustment or additional verification. The list may include expansion devices, pressure controls, controller refrigerant selections and relevant liquid-line components. The contractor should connect each proposed change to a document or an identified condition on the asset.
This review prevents two opposite mistakes. One is leaving every setting unchanged because the system still switches on. The other is replacing every component without explaining why. A useful quotation distinguishes required conversion work from repairs that would also be necessary if the system stayed on R404A.
Ask for separate descriptions of component selection and commissioning. Buying a suitable part does not establish that it has been installed or configured correctly. A commissioning record should show what was verified, under what load and with which reference data. That record allows future service to begin from the final configuration rather than reconstructing the conversion from invoices.
Lubricant compatibility does not end with the word POE
Record the specified lubricant, viscosity and installed service history. A general statement that an HFC refrigerant is associated with POE lubricant leaves the exact compressor requirement unresolved. Different approved oils or equipment histories can require different decisions. Let the compressor manufacturer establish the applicable specification.
If the machine has already been converted from an older refrigerant, identify that earlier work. The current R404A label alone may not reveal the original lubricant or whether the previous conversion was completed as intended. Missing records deserve explicit investigation rather than a confident assumption that every internal condition matches the current label.
Separate lubricant identification from contamination or burnout assessment. A machine with a serious mechanical failure may require a cleanup scope regardless of the future refrigerant. Adding that work only to the R407A option can make the comparison misleading. Conversely, omitting it from both options makes both quotations incomplete. The fair comparison uses the same known asset condition.
Establish the R404A baseline before judging the alternative
Check whether poor current performance comes from an identified repair need rather than the refrigerant choice. A damaged fan, obstructed coil, unstable control or documented leak can distort the baseline. If the R404A machine is not operating as intended, its present electricity use and cooling performance cannot fairly represent a healthy R404A option.
Request a clear separation between observed symptoms, confirmed faults and unresolved questions. “The room took longer to recover” is an observation. “This component failed a specified test” is a diagnosis. “R407A will fix the problem” is a proposed outcome that needs supporting evidence. Keeping those statements separate makes the decision easier to assess.
For wider selection questions beyond this pair, consult the existing commercial refrigeration refrigerant selection guide. This comparison should help narrow a documented R404A/R407A decision, rather than replace the system assessment that determines whether either option is appropriate.
Compare staying, converting and replacing on the same asset
Keeping an approved R404A charge, converting an eligible system to R407A and replacing the equipment are different scopes. Compare them with the same information about condition, expected operating duty and available downtime. A cheaper refrigerant cylinder does not necessarily create a cheaper project once component changes and commissioning are included.
| Option | Evidence needed | Main decision |
|---|---|---|
| Continue R404A service | Approved asset; confirmed repair scope | Is the existing asset worth maintaining? |
| Convert to R407A | OEM support; suitable components and duty | Does conversion meet the required load? |
| Replace equipment | Design and applicable new-system requirements | Is a new asset the better investment? |
Keep required repairs common to all relevant options. Then show the additional conversion work separately. If a proposal changes the asset's intended capacity or replaces extensive portions of a system, the regulatory classification may also change. A maintenance comparison must not quietly become a new-system installation comparison without explaining the difference.
Environmental metrics do not override application restrictions
A lower GWP can be relevant to planning, but it answers only part of the decision. An alternative can have lower GWP than R404A and still fail an applicable limit for a newly installed system. Conversely, restrictions on new equipment do not automatically mean that every existing R404A appliance must immediately stop operating.
EPA's current HFC phasedown questions and May 2026 Technology Transitions fact sheet explain the distinction between existing-equipment service and new-system requirements. The contractor must determine the actual subsector and scope of work rather than use “R404A is banned” as a blanket explanation.
Document the regulatory question in the proposal when it affects the choice. Which restriction applies to this asset and this work? Which compliance date or exception matters? If the answer relies on a current rule, preserve its version and check the actual text. A general transition headline is too broad to decide a specific refrigeration conversion.
Make the quotation reviewable before approving the outage
A useful proposal names the starting refrigerant, intended refrigerant, supporting OEM documents, component changes, service procedure and acceptance conditions. It also identifies unresolved information. If approval depends on a model suffix that has not yet been confirmed, say so before the project is booked.
Ask how the contractor will protect the business during the interruption. Confirm the responsibilities for product transfers, access to equipment and the return-to-service decision. Avoid a schedule that assumes the equipment will recover instantly after work is complete. The required operating checks and the business's own stock-handling decisions should have realistic space in the plan.
Separate optional work from required work. Managers can then see whether they are approving a conversion, a repair, preventive maintenance or several scopes together. If the proposal includes a contingency for unexpected component condition, state how that finding will be documented and who can authorize the additional work. That is more useful than a vague promise of an uncomplicated refrigerant swap.
Correct cylinder identity comes after the selection
Once the approved service plan specifies the refrigerant, match the order to that exact product. The current GetFreon catalog includes R404A refrigerant and R407A refrigerant. Confirm the selected page and packaging information against the contractor's written requirement; product availability alone does not establish compatibility.
EPA's refrigerant sales restriction generally limits stationary refrigerant purchases to appropriately certified technicians and qualifying employers or authorized representatives. Arrange the required purchasing documentation with the supplier. The limited exception for certain small automotive refrigerant cans does not create a residential or commercial stationary-system exemption.
Do not order both products as interchangeable options for the technician to mix. If the intended refrigerant remains undecided, finish that decision first. A correct order contains the documented product identity and quantity derived from the approved service scope. Avoid estimating the final charge solely from a generic percentage found for another machine or another conversion route.
What the completed conversion record should establish
The final record should identify the asset, date, starting and final refrigerants, installed components and document references. It should also state the operating conditions under which the contractor checked performance. A successful startup is useful, but it is weaker evidence than a documented acceptance assessment under the agreed duty.
Preserve the distinction between required targets and observed measurements. A controller setpoint is not the same as a measured product or room temperature, and a displayed refrigerant selection is not proof of a completed conversion. Record the checks that establish the final configuration, including any applicable protective functions.
If the contractor identifies a limitation, keep it visible in the handover. For example, an acceptance check may cover the observed load while a higher-load verification remains outstanding. State that boundary instead of treating the first check as proof of every future condition. A clear follow-up responsibility helps the manager act if recovery or capacity later differs from the agreed expectation.
Keep a decision worksheet with the proposal
Use one worksheet for the actual asset, with separate columns for the continued R404A option and the proposed R407A option. Start with the common facts: equipment identity, confirmed faults, required refrigeration duty and available interruption window. Then enter the documentary basis for each refrigerant. If a field remains unknown, keep it marked unknown rather than borrowing information from another installation.
For capacity, enter the source and rating conditions beside the result. For the compressor, enter the applicable model range and any protection package. For the expansion device, enter the manufacturer's selection and the parts retained or changed. For controls, identify the final refrigerant configuration and the checks the technician will perform. The worksheet should help a reviewer trace the recommendation, not merely collect favorable specifications.
Add an explicit decision field: proceed, continue existing service, investigate further or compare replacement. Also name the person responsible for resolving each open question. That prevents an uncertain item from disappearing when the quotation moves from the technician to purchasing. The worksheet is an editorial project-management aid, not a substitute for the OEM's engineering selection or a statement that every field is legally mandatory.
Assess energy evidence on a comparable operating period
Do not evaluate a conversion from one utility bill without examining what else changed. Ambient conditions, operating hours, loading and equipment repairs can all differ between periods. A manager who needs an energy comparison should agree with the contractor on the measurement boundary and which operating data can make the periods reasonably comparable.
Clarify whether a quoted efficiency figure describes compressor cycle performance or the complete refrigeration system. Fans, defrost and other electrical loads can sit outside a compressor-only comparison. A modeled coefficient of performance therefore should not be presented as an identical percentage reduction in the site's electricity bill. Preserve the model boundary and the expected uncertainty in the proposal.
After work, compare the agreed measurements with their baseline and note any simultaneous changes. If the conversion included cleaning coils or replacing a failed fan, those improvements are part of the outcome but should not all be attributed to the refrigerant. If no suitable baseline exists, document acceptance of the required operating duty without inventing an energy-saving result. That is a more useful handover than an unsupported claim of a measured improvement.
Questions to take into a contractor discussion
Before approving an R404A-to-R407A proposal, ask which document supports the exact compressor and which duty point was used for the capacity comparison. Ask whether the existing expansion valve, element and controls can remain, and what proof supports each decision. Request the lubricant specification and applicable protection requirements in the written scope.
Then ask what the quotation would look like if the asset stayed on R404A. Repairs needed in both cases should be easy to identify. Ask what condition would make replacement preferable, and whether the proposed scope could trigger new-system requirements. These questions keep the discussion focused on the asset rather than the attractiveness of a refrigerant name.
Finally, ask who will verify the finished work and what will be delivered in the handover. A manager does not need to perform the technical measurements to require a useful record. The goal is a documented decision that the next service technician can understand, with the system identity and remaining limitations preserved.
Resolve conflicting recommendations before placing the order
If two contractors recommend different refrigerants, ask each to identify the evidence for the installed model and duty. A disagreement can arise because they assumed different asset conditions or because one included necessary component changes that the other omitted. Comparing the documents and scopes is more productive than choosing the recommendation with the strongest verbal assurance.
Where the disagreement concerns an OEM requirement, obtain clarification from the relevant manufacturer or its authorized technical channel. Preserve the question, equipment identity and written answer. A distributor's product listing can confirm what is offered, but it cannot decide whether an undocumented component conversion is approved. Keep the purchase pending until the equipment selection is resolved.
The final decision should be understandable without recreating the conversation. Record why the selected option fits, which alternatives were considered and what limitations remain. That short explanation becomes especially valuable when a different technician services the asset later or a manager needs to review another quotation.
Frequently asked questions
Is R407A a drop-in replacement for R404A?
No universal drop-in claim is justified. Some existing R404A systems can be converted when the manufacturers support the compressor, duty, valve, controls and required protection. A conversion can involve component or setting changes and a documented service procedure. Confirm the specific equipment rather than assuming that both refrigerants being A1 or associated with POE establishes interchangeability.
Can R407A be added to an R404A charge?
Do not mix them. The intended refrigerant specification belongs to the finished manufactured blend, and a conversion must follow the approved recovery and service procedure. If the current charge is uncertain or mixed, the contractor needs to resolve that condition before normal service. Adding one blend to another does not create an approved alternative.
Does R407A always reduce cooling capacity?
The Chemours theoretical examples show lower relative capacity under their stated conditions. Those examples cannot predict every compressor and installation. Obtain a common-duty OEM comparison and assess the actual load margin. A machine that can meet its required duty after conversion and one that cannot may reasonably reach different decisions using the same candidate refrigerant.
Can the existing R404A expansion valve remain?
Possibly, but the valve body, element, capacity and application must be reviewed with the manufacturer. Some devices require a different element or complete replacement. An adjustment alone should not be assumed adequate. The quotation should explain which parts remain, which change and how correct operation will be checked.
Does lower GWP mean R407A is approved for every new system?
No. Compare the applicable subsector restriction and scope of work with current EPA requirements. A lower-GWP alternative to R404A can still exceed a limit that applies to new equipment. Existing service, conversion and new installation are different regulatory questions. Do not turn a relative environmental improvement into a blanket compliance claim.
Should a healthy R404A system be converted immediately?
The refrigerant comparison alone cannot answer that. Review asset condition, supported conversion options, operating duty, downtime and the applicable rules. Keeping a properly maintained existing system may be a defensible option; a supported conversion or replacement may fit another asset better. Require a written comparison that explains the actual reason for the recommendation.
Which refrigerant should I order before the technician arrives?
Order the exact refrigerant only after the qualified contractor has identified the installed charge and approved service scope. Confirm purchasing eligibility, product identity and documented quantity. If the plan is still under review, ask the contractor to finish it before placing the order. That avoids buying a cylinder that the equipment cannot appropriately use.
