R407A vs R448A for Existing Commercial Refrigeration

For equipment already running R407A, the useful comparison is continued R407A service versus a supported conversion to R448A. R448A has lower global warming potential, but that difference does not establish compressor compatibility, energy savings, or an economic reason to change a working circuit. Begin with the actual R407A installation and the problem or objective behind the proposed change.

Both refrigerants serve commercial refrigeration applications, both are A1 blends, and both have meaningful temperature glide. An R407A circuit therefore presents a different starting point from an R404A circuit. Familiar claims about moving from R404A to R448A cannot simply be carried across to this pair.

This guide explains the differences that matter to owners and refrigeration contractors: composition, comparable GWP and glide data, documented conversion guidance, compressor limits, component selection, and the evidence needed to justify the project. Refrigerant recovery, charging, electrical work, and adjustments require qualified professionals following the instructions for the installed equipment.

R407A vs R448A at a glance

Composition follows ASHRAE's refrigerant designations. GWP, safety class, and ozone depletion values come from the same EPA remote-condensing-unit table. Glide figures use the explicitly stated conditions in BITZER's Refrigerant Report, table 8; they are reference properties, not operating targets.

The shared R32, R125, and R134a ingredients do not make these fluids interchangeable. Their proportions differ, and R448A also contains two HFO components. A refrigerant designation identifies the finished blend, so choosing a cylinder by an ingredient, an approximate pressure, or the first three digits of its name is insufficient.

Chemours identifies R407A for low- and medium-temperature refrigeration, including established replacement applications. Solstice identifies R448A as a zeotropic HFO blend for commercial refrigeration. These overlapping application descriptions explain why the pair comes up in service planning. They do not determine which fluid an individual compressor can use.

Likewise, R407A is not R407C or R407F. An equipment document that names one member of that family does not silently approve the others. Keep the complete refrigerant designation in purchase orders, selection reports, controller records, and equipment labels.

Start with a sound R407A service baseline

A comparison is useful only after the current system is understood. For an R407A walk-in with a repairable leak, the baseline is a sound repair and continued operation with its approved refrigerant. Comparing conversion with an unrepaired, underperforming system can make ordinary maintenance benefits look like benefits of R448A.

For a circuit operating satisfactorily, identify the proposed reason for changing it. Lower refrigerant-related emissions, a planned equipment modification, or standardization across supported assets can be legitimate objectives. “The other refrigerant is newer” does not tell an owner what the project will accomplish or how much interruption is justified.

Use the latest retrofit label and service history as well as the original nameplate. A system built for another refrigerant may now run R407A after earlier compressor, oil, or valve changes. The current configuration is the asset being evaluated. Reusing its original factory specification without those changes may describe equipment that no longer exists.

If the actual starting refrigerant is R404A, use the separate R448A versus R404A replacement guide. For a broader choice between repair, conversion, and new equipment, see choosing a commercial refrigeration refrigerant. Here, the central question remains what R448A changes relative to the R407A circuit already in service.

Can R448A replace R407A? What the documentation establishes

There is published support for investigating this conversion. Solstice explicitly names R407A among the refrigerants from which existing supermarket systems can be retrofitted to N40, its R448A product. That is a relevant starting point for this pair, rather than an inference from an R404A brochure. See Solstice's supermarket application discussion.

Copeland also publishes changeover bulletin 2015ECT-2 for R404A/R407A/C/F to R448A/R449A. It explicitly includes an R407A starting point. Among its considerations are approved POE lubricants, possible expansion-valve and pressure-control changes, and compressor-specific review of liquid injection for low-temperature applications. It prohibits mixing the new refrigerant with another refrigerant.

Neither document is a universal approval for every R407A machine. The refrigerant supplier describes an application opportunity; the compressor manufacturer defines requirements within its own scope. The equipment manufacturer and component suppliers still need to support the assembled system and intended duty.

A convincing proposal connects those levels of evidence. It identifies the installed compressor, shows an R448A selection at the site's conditions, and explains how the remaining equipment will support it. A generic list saying “R448A compatible” is weaker than a selection report with the actual model suffix, voltage, speed, cooling arrangement, and application limits.

When a document covers multiple starting refrigerants, read the relevant step carefully. Some numerical examples or charging references may still use R404A as their baseline. Their presence in a document that also mentions R407A does not turn every R404A number into an R407A instruction. The contractor should resolve the applicable procedure before the outage, especially for a system that has already been converted once.

Temperature glide is already part of the R407A system

A major difference from an R404A comparison is that R407A already has substantial glide. Both R407A and R448A change temperature during evaporation or condensation at constant pressure. R448A is not introducing that behavior into an otherwise near-constant-temperature R407A circuit.

BITZER's reference values above put total bubble-to-dew glide at 6.5 K for R407A and 6.2 K for R448A at 1.013 bar absolute. That is a difference of only 0.3 K at that reference condition. It does not establish identical evaporator behavior, nor does it justify calling R448A a dramatically higher-glide refrigerant than R407A. Actual glide depends on operating conditions, as the report states.

Different publications may give different-looking glide figures because they describe different pressures or portions of the refrigeration process. A total glide value at atmospheric pressure should not be compared directly with an effective evaporator glide under working conditions. Before accepting a numerical claim, check its pressure, phase endpoints, and units. A kelvin temperature interval has the same size as a Celsius interval; it is not the same size as a Fahrenheit interval.

The practical service conventions remain important with either blend. Use the correct refrigerant's dew reference for superheat and bubble reference for subcooling. Equipment ratings and heat-exchanger analysis may use a stated mean-temperature convention. Danfoss's paper on glide refrigerants explains why dew, bubble, and mean temperatures serve different purposes.

Imagine two selection sheets carrying the same printed evaporating temperature. If one uses dew point and the other uses a mean value, they may represent different coil conditions. The refrigerant comparison can then appear better or worse because the inputs changed. Ask for the convention beside each temperature, with the same required room or product duty on both selections.

For an existing R407A installation, the useful question is which pressure-to-temperature references and targets must change for R448A. Copying the old pressures does not preserve the intended temperatures. GetFreon's superheat and subcooling verification guide provides measurement context; the equipment's instructions determine its acceptable operating values.

Compare capacity across the circuit's real operating range

R407A and R448A do not have one universal capacity relationship. Compressor displacement, refrigerant properties, suction conditions, condensing conditions, and the installed cooling arrangement affect the comparison. The owner needs to know whether the proposed system can meet the same load over the conditions it will actually encounter.

There is a useful caution in Chemours' R407A properties bulletin, table 2b: its theoretical performance comparison separates medium- and low-temperature conditions and states the assumed evaporating temperature, condensing temperature, superheat, and subcooling. The comparison is with R404A. It supplies information about R407A under those assumptions, not a measured R407A-to-R448A result.

Combining that table with an unrelated R448A case study would not create a valid head-to-head comparison. Even if both sources use R404A as a reference, their compressors, test conditions, and measurement boundaries may differ. A claim derived by subtracting their advertised improvements needs a common underlying test basis before it can support an investment. Request a fresh paired selection when that basis is absent.

Request paired selections for the existing compressor configuration wherever the manufacturer supports both refrigerants. Hold the useful duty consistent, state the temperature conventions, and identify any changed assumptions. If a replacement compressor is proposed, distinguish the result of that equipment change from the result of changing refrigerant.

For a cooler, evaluate demanding ambient conditions and recovery after the site's normal loading pattern. For a freezer, give particular attention to the low-temperature operating envelope and discharge-temperature requirements. For a rack, review the relevant suction group and its compressor combinations. An acceptable result for one group does not establish suitability for the whole store.

Capacity and electrical input belong together. A selection showing lower input power is incomplete if it also cannot carry the required load. Equally, a favorable full-load point does not describe periods when only part of the rack is running. Ask whether the proposed controls and available compressor steps support both peak duty and reduced demand.

The practical decision is about margin. If the R407A system already struggles during peak operation, a conversion proposal must explain how adequate capacity will be established. If it has spare capacity, document how much of that margin remains under the proposed configuration. An unquantified statement that the system “should have enough” is a poor basis for risking refrigerated inventory.

Actual compressor requirements show why model details matter

Copeland's RF compressor guidance for R448A and R449A, updated March 2026, requires a 220°F discharge-line temperature cutout located six inches from the compressor. It also advises against liquid-line-to-suction-line heat exchangers in that application. These are concrete RF requirements, not settings to copy onto every compressor.

A different example appears in Copeland's European ZF*K4E-TW* technical information. For the covered ZF24–48K4E-TW* retrofit applications, it requires liquid injection with a DTC valve for R407A, R407F, R448A, or R449A. Its discussion also excludes the identified ZF24–48KVE vapor-injection models from the R404A changeover described there.

That second document starts from R404A; it is useful here as evidence that model generation and injection arrangement change the answer. It is not a standalone procedure for converting any existing R407A ZF installation. A previous conversion may already have included the prescribed hardware, or may have a configuration that needs fresh engineering review.

Discharge-temperature protection and active compressor cooling also serve different functions. A cutout stops operation at its specified condition; an injection arrangement may be needed to permit operation within the approved range. A proposal should identify what is required, what is already installed, and what must be added or changed. The presence of a temperature alarm alone does not answer those questions.

Do not import a statement that R448A runs hotter than R404A and relabel it “hotter than R407A.” Obtain the R407A and R448A results for the actual model and duty. The established point is that both the operating envelope and its protection requirements must be respected, not that this pair always produces a fixed temperature difference.

Expansion valves and controllers need a pair-specific review

An R407A valve review should begin with the actual valve and element, not with the assumption that a valve once used on R404A remains installed. Earlier service may have changed its thermostatic element, orifice, distributor, or complete assembly. Record what is present before deciding what can remain.

Parker Sporlan bulletin 210-40-4, April 2025, assigns R407A to system-refrigerant code V and R448A to code D. Its tables include some shared thermostatic-charge recommendations while listing refrigerant-specific nominal capacities. Thus, a shared element recommendation does not by itself establish adequate valve capacity.

That distinction prevents two opposite purchasing mistakes: automatically replacing every valve, or assuming none require work. The contractor should check the identified valve at the required load and pressure conditions, then specify retention, an approved modification, or replacement. Where the valve is retained, the quote should still cover verification with the selected refrigerant.

Electronic control adds another layer. A controller with an R448A selection may be capable of interpreting the new pressure-temperature relationship, but that does not verify its sensor setup or prove that the rest of the configuration is appropriate. A temperature displayed on a screen can be measured directly or calculated from pressure. The distinction matters when checking the conversion.

Ask for the old and proposed refrigerant selections, the reason for each control change, and the final settings record. For several evaporators on a shared circuit, identify which local controls need attention. Reconfiguring the rack controller alone may leave a separate case controller or pressure regulator using assumptions from the R407A setup.

The acceptance question is practical: does the equipment feed and control the load properly during its intended operating modes? A compressor running without an immediate trip is not sufficient evidence. Stable temperatures, appropriate operating measurements, and correct refrigerant references should agree.

Shared oil families do not erase the system's history

Many supported applications of these blends use POE lubricant, but “both use POE” is not an oil specification. Grade, viscosity, compressor approval, contamination, and the existing service history still matter. The cost of a conversion can change significantly if those details are unknown.

BITZER's A1 refrigerant oil table lists BSE32 for R407A and R448A in its reciprocating-compressor section. The same document has separate screw-compressor entries and oil types. This is a useful example of shared lubricant support within a defined application, rather than permission to use one oil throughout every compressor family.

For a system previously converted from R22, obtain the earlier oil and compressor records. An invoice that says “converted to R407A” does not fully describe residual oil, later additions, or a subsequent compressor replacement. If records are missing, the contractor should explain how the uncertainty will be evaluated and what work the estimate includes.

Separate pre-existing cleanup from conversion-specific work. If an R407A compressor has failed and contaminated the circuit, a viable retain-and-repair option may also need cleanup and lubricant work. Charging all of that cost to the R448A option would distort the comparison. Conversely, shared oil-family compatibility should not be used to omit work required by the actual condition of the system.

Energy savings must be measured against R407A

Manufacturer material for R448A often reports results against R404A. For example, the Solstice N40 low- and medium-temperature brochure describes supermarket trials using that baseline. Those reports establish neither a guaranteed result nor a transferable percentage for an R407A conversion.

Ask for the proposed R407A-to-R448A comparison explicitly. It should use the same load assumptions and identify simultaneous changes such as new compressors, repaired condenser fans, revised controls, or case replacements. Those changes may improve the project, but their contribution should remain visible when the owner evaluates the refrigerant decision.

A measured baseline is most useful when the R407A system is functioning properly. If a major failure prevents that measurement, say so and use a clearly labeled engineering estimate. An estimate can support a decision; presenting it as measured site savings cannot.

Define the electricity measurement boundary before promising payback. Refrigeration submetering can be more informative than a whole-building bill that includes HVAC, lighting, and kitchen equipment. Weather, trading hours, product loading, and control schedules still affect comparisons. Collect the context needed to explain a change rather than assigning every reduction to the refrigerant.

Also distinguish energy efficiency from operating capacity. A site might value improved temperature recovery even without a demonstrated energy reduction, while another needs an evidenced reduction in electricity cost. Name the intended benefit and establish how it will be checked. If the business case depends on savings that have not been demonstrated for R407A, treat that part of the case as uncertain.

What the lower GWP means for this pair

Using the EPA values of 2,110 for R407A and 1,387 for R448A, R448A has approximately 34% lower GWP. This compares the warming impact assigned to equal masses emitted. It does not mean a converted store will use 34% less electricity or have 34% lower total emissions.

A simple illustration makes the distinction clearer. Emitting 10 kilograms of R407A corresponds to 21.10 metric tonnes of carbon dioxide equivalent on this basis. Emitting the same mass of R448A corresponds to 13.87 tonnes, a difference of 7.23 tonnes. These are illustrative calculations, not assumed leakage rates or measured results for a particular store.

A real project may have a different installed charge, leakage history, and remaining life after conversion. Use those site inputs rather than assuming equal annual losses automatically. Recovery during the project also belongs in the environmental assessment. The published refrigerant property is one input to the result; the installation and its maintenance determine how much refrigerant is actually emitted.

Keep leak prevention as a separate objective. Repairing a recurring R407A leak has value even if the refrigerant is retained. Where an R448A conversion is supported, it should accompany a sound leak-management plan. A lower-GWP replacement is not a reason to accept continued losses.

For reports using another scientific assessment basis, obtain both refrigerants' values on that basis. Do not combine one value from a newer assessment with another from an older one and describe the resulting percentage as a direct comparison.

Separate existing-system service from new-system restrictions

A service decision and a new-equipment specification can have different regulatory answers. The EPA SNAP table used for the property comparison expressly notes that Technology Transitions restrictions may also apply. Its acceptance listing does not settle every rule affecting a project.

EPA's Technology Transitions rulemaking page includes a May 2026 reconsideration final rule affecting several refrigeration categories. Consult the current sector restrictions for the actual project, with applicable state and local requirements, rather than relying on a generic claim that R407A is banned or R448A is permanently compliant.

Have the contractor identify whether the scope is maintenance, a refrigerant conversion, or work treated as a new installation. If a planned remodel expands from changing refrigerant to replacing major assemblies, revisit that classification. The business decision should reflect the final scope, including any applicable leak-repair obligations, rather than the small job originally discussed.

Compare the additional cost of conversion

Start with the cost of making the R407A circuit serviceable for its intended remaining use. Then identify the additional cost of choosing R448A: engineering review, conversion-specific components, refrigerant handling and supply, control work, commissioning, and any extra interruption. Shared repairs should appear consistently in both options.

Purchase price per cylinder is only one part of that difference. A technically acceptable conversion may still be unattractive if the equipment will be retired during an imminent store remodel. A well-supported conversion may be more reasonable where a major planned outage already provides access and the retained equipment has useful life ahead.

Ask the quote to distinguish known work from allowances. An identified expansion-valve replacement is different from an unspecified contingency for “valves as needed.” Likewise, a confirmed compressor-protection package is more reviewable than an assumption that the existing hardware will suffice. Resolve important eligibility questions before treating the total as fixed.

Business interruption can outweigh modest differences in material cost. Include any extra product movement, temporary cold storage, and restart coverage caused by conversion. Assign responsibility for a delayed restart while the food can still be protected. These costs should reflect the particular site's operation, not a generic per-pound retrofit price.

If a payback calculation is offered, examine the incremental cost and the R407A-based annual savings separately. A project can have a worthwhile environmental or service-standardization objective without a short energy payback. Describe that value honestly instead of filling the calculation with an unsupported savings percentage.

Three R407A situations that lead to different decisions

A reliable cooler needs a localized repair

Suppose an R407A cooler has satisfactory capacity, a repairable leak, and a short remaining period before replacement. Establish the repair-and-retain option first. If conversion adds component work and downtime without an evidenced benefit over that period, continued correctly specified R407A service may be the reasonable outcome. The service decision should still address the leak and any applicable obligations.

A low-temperature circuit needs a compressor replacement

The replacement creates a useful point to compare supported options, but its model must be selected for the full application. Price the R407A repair and the R448A alternative with their respective cooling and protection requirements. If the R448A proposal relies on a different compressor generation, show that explicitly. Approval of the replacement model cannot be assumed from the name of the failed compressor family.

A supermarket wants fewer service refrigerants

An owner with some R448A circuits may consider converting a remaining R407A rack to simplify stock and service coverage. Review that rack independently, including each suction group's duty and the current controls. Standardization has practical value only if the resulting installation is supported. Where one circuit cannot reasonably be converted, retain an accurate mixed-refrigerant asset register and purchasing plan rather than forcing a common cylinder onto incompatible equipment.

These are decision examples, not reports of completed installations. Each begins with R407A and a different business trigger. The refrigerant properties remain the same, while the equipment condition, planned life, and cost of interruption change the sensible choice.

Order the refrigerant that matches the approved work

Once the service or conversion decision is documented, match the purchase to it. GetFreon's R407A refrigerant listing and R448A refrigerant listing each identify a 25 lb product. The shared package size does not imply the same installed charge or make the refrigerants interchangeable.

The technician's approved job plan determines the required service quantity. Cylinder quantity also depends on package size and usable inventory. Confirm the current product details and availability before committing to a shutdown; this comparison does not quote live prices or promise stock.

Keep the final order consistent with the circuit identification. After an approved conversion, the equipment label, controller refrigerant selection, maintenance record, and future service instructions should all reflect R448A. Where R407A is retained, keep that decision equally clear so a later emergency purchase does not become an accidental substitution.

Frequently asked questions

Can R448A be added to a system that contains R407A?

No. A supported conversion is a separate professional procedure that includes handling the existing refrigerant appropriately. R448A is not an R407A top-off product. An uncertain charge identity should be resolved before service or purchasing decisions.

Does R448A have much more glide than R407A?

The same-condition BITZER reference values shown above are close: 6.2 K for R448A and 6.5 K for R407A. Working-system values depend on conditions. Both require their own pressure-temperature data and correct measurement conventions.

Will every R407A compressor run on R448A?

No universal approval follows from the refrigerant names. Verify the exact compressor and equipment configuration, operating envelope, and required protection. Supplier retrofit literature establishes a candidate application, not approval of an unidentified machine.

Is R448A always the less expensive choice?

No. Compare the complete supported project with continued R407A service over the equipment's intended remaining use. Refrigerant price alone omits component changes, interruption, commissioning, and any uncertain energy benefit.

The practical choice: retain R407A when sound service meets the equipment's needs and the owner's plan. Choose an R448A conversion when the actual installation is supported and its additional work delivers a justified benefit. The strongest comparison follows the existing R407A circuit all the way from diagnosis to the final refrigerant order.

Reviewed October 1, 2026. Primary references appear beside the relevant claims. Manufacturer examples retain their stated model and application limits; current instructions for the installed equipment govern. Images illustrate general commercial refrigeration settings.