REFRIGERANT GAS MAXREF R‑407C

Mexref R-407C is a widely used HFC refrigerant blend composed of R-32 (23%), R-125 (25%), and R-134a (52%), specifically formulated to replicate the performance characteristics of legacy R-22 systems. By closely matching the pressure–temperature relationship and cooling profile of R-22, Mexref R-407C provides a practical transitional solution for retrofitting existing HVAC systems without requiring major component redesigns.

It is particularly valuable in markets where R-22 phase-out regulations demand an immediate, ozone-friendly replacement. Mexref R-407C offers zero ozone depletion potential (ODP = 0), ASHRAE A1 safety classification (non-flammable, low-toxicity), and a moderate GWP (~1774), making it a balance between performance, safety, and environmental compliance.

Though it is not a “drop-in” refrigerant, it is approved by many OEMs for use in residential, commercial, and light industrial HVAC systems with relatively simple retrofitting procedures, typically involving oil change to POE lubricants, expansion valve recalibration, and liquid charging protocols.

Key Features:

• Zero Ozone Depletion Potential (ODP = 0) – environmentally safer alternative to R-22.

• ASHRAE A1 Classification – non-flammable, low-toxicity, safe for residential and commercial use.

• Close Performance Match to R-22 – similar system pressures and cooling capacity, easing retrofits.

• Retrofit-Friendly – requires minimal hardware changes compared to higher-pressure refrigerants like R-410A.

• OEM-Approved – widely accepted by manufacturers for R-22 replacement projects.

• Versatile Application – suitable for HVAC, packaged rooftop systems, VRF/VRV units, and heat pumps.

Applications:

• Residential HVAC Retrofits – replacement for R-22 in ducted and split systems.

• Commercial Rooftop & Packaged Units – efficient upgrade solution for medium-capacity installations.

• Variable Refrigerant Flow (VRF) / Variable Refrigerant Volume (VRV) Systems – used in older equipment transitioning off R-22.

• Heat Pumps – compatible with residential and light commercial heat pump systems originally designed for R-22.

• OEM-Approved Conversions – widely recognized by HVAC manufacturers as a retrofit solution.

Usage:

• Retrofit Procedure – complete evacuation of R-22 before charging with R-407C.

• Oil Change Required – switch to POE lubricants; mineral oil from R-22 systems is not compatible.

• Charge in Liquid Phase – due to zeotropic blend properties, R-407C must always be charged in liquid form to maintain blend consistency.

• Expansion Device Adjustments – minor recalibration may be required to account for glide and performance differences.

• System Glide Management – as a zeotropic refrigerant, R-407C has temperature glide (up to ~7°C), which must be considered in superheat and subcooling calculations.

Benefits at a Glance:

• Easy transition from R-22 systems with minimal equipment changes

• Zero ODP, safer for the ozone layer

• Non-flammable, safe for residential and commercial use

• Widely available and supported by OEMs

• Balanced environmental profile vs. R-22 and R-410A

FAQs:

Is R-407C a drop-in replacement for R-22?
Not exactly. While R-407C is designed to mimic R-22 performance, it requires system modifications, including POE oil conversion and charging procedure changes.

Why choose R-407C instead of R-410A for retrofits?
Because R-407C has similar pressures and characteristics to R-22, it requires fewer hardware modifications. R-410A operates at much higher pressures and is only suitable for new equipment.

What about temperature glide in R-407C?
R-407C is a zeotropic blend, meaning it has a temperature glide (~7°C). This requires careful charging (in liquid form) and adjustment of superheat/subcooling settings.

Will R-407C remain available long term?
Yes, though its moderate GWP (~1774) means it is subject to phasedown under F-Gas and Kigali Amendment regulations. Many OEMs continue to support it as a transitional refrigerant.