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Module 1 of 8 120m 10 exam Qs

Low-GWP Refrigerant Properties

Properties and characteristics of low-GWP refrigerants including R-32, R-454B, R-1234yf, R-1234ze, and R-290 - comparing GWP values, pressure-temperature relationships, and performance to legacy refrigerants.

  • Compare GWP values of low-GWP refrigerants to legacy HFC refrigerants they replace
  • Identify the safety classification (A1, A2L, A3) of common low-GWP refrigerants
  • Explain how temperature glide affects system design and charging for zeotropic low-GWP blends
  • Describe the operating characteristics of R-32, R-454B, R-1234yf, and R-290

Lesson 1

Why the Industry Is Transitioning to Low-GWP Refrigerants

The Problem With High-GWP Refrigerants

Global Warming Potential (GWP) measures how much heat a greenhouse gas traps in the atmosphere relative to carbon dioxide (CO2, which has a GWP of 1). Legacy HFC refrigerants have extremely high GWP values - R-410A has a GWP of 2,088, and R-404A has a GWP of 3,922. When these refrigerants leak into the atmosphere, they contribute significantly to climate change.

2,088
R-410A GWP (Being Phased Down)
675
R-32 GWP (Replacement)
466
R-454B GWP (Replacement)
3
R-290 GWP (Natural Refrigerant)

The AIM Act and HFC Phasedown

The American Innovation and Manufacturing (AIM) Act, signed in 2020, mandates an 85% phasedown of HFC production and consumption by 2036. This is not a ban on HFCs but a graduated reduction in the total amount produced and imported. The phasedown drives the transition to lower-GWP alternatives.

2020
AIM Act Signed
85% HFC phasedown by 2036 mandated
2022
First Allocation Period
HFC production allowances begin decreasing
2025
R-454B Equipment Launches
Major manufacturers release A2L equipment
2025
New Equipment Transition
EPA restricts high-GWP HFCs in new residential AC
2036
85% Phasedown Complete
HFC production at 15% of baseline levels
Key Takeaway

The AIM Act mandates an 85% phasedown of HFC production by 2036 - technicians must be prepared to work with low-GWP replacements like R-32 (GWP 675), R-454B (GWP 466), and R-290 (GWP 3) that are replacing R-410A and R-404A.