Gary Parker – Refrigerants Product Manager
Refrigerant History Status of the HCFC ( R22) Phase out
Ozone Friendly Alternatives • Choosing the Best Retrofit Solution • Lubricants and how they impact performance • Refrigerant Blends and how to apply them
Changes in the Legislative Landscape • Global Warming • What it means to you and your customer
New Generation Alternatives • HFO Refrigerants
Fluorine based Refrigerant History • CFC = Chlorofluorocarbon (Phased out in 1996) • R11, R12, R113, R114 R500, R502
• HCFC = HydroChloroFluoroCarbons (Phase out in 2020) • R22, R123, R401, R402, R408, R409, R414 • HFC = HydroFluoroCarbons (Phase out under consideration) • R32, R125, R134a, R143a, • R404, R407, R410, R422A,B,C,D R438A, R507 • HFO = HydroFluoroOlefins (Phasing in now) • R1233ZD, R1234YF, R1234ZD, R1234ZE • R444, R445, R446, R447, R448,R449,R450
Ozone Friendly Alternatives • Most all Refrigerant Blends are a mixture of some or all of the following components. • HFC R-32, R-125, R-134a, R-143a • Hydrocarbon R-200 Series(Propane), R-600 Series (Butane)
• The mixture and percentage of each component varies depending on the target application for the blend. • Design Factors include capacity, mass flow and oil miscibility . • (R290/R600) used solely to promote oil return in Mineral Oil systems, and impact performance.
Blend composition
Low Temperature R22 Alternatives
Low Temperature R22 Survivors
HT/AC R22 Alternatives
HT/AC R22 Survivors
Lubricant Choice and the Effect on Performance • Proper Oil Return is critical for any Refrigeration or AC System. Miscibility between the refrigerant and the oil is essential. • Some refrigerants claim to be no-oil-change solutions. In most cases, they have a very narrow application window and lower capacity.
• With a non-miscible combination oil logging can occur, which impacts compressor life and performance. Have you ever added oil ? • It is now widely agreed that only percentage of POE is required to ensure proper oil return. • System design and operating temperature will play a key role in determining that % . • Additives are now being marketed (Super Change) that improve miscibility, limited to basic close coupled systems..
Liquid Receivers & Hydrocarbon Blends • Hydrocarbons (Propane-Butane) are used to help with HFC- mineral oil/AB miscibility. • The hydrocarbon only assist oil return in the gas or vapor state, using velocity to move the oil. • In the liquid form, hydrocarbons are of no assistance and the oil can get stranded on top of the refrigerant. • To ensure proper oil return, you need to use a truly miscible combination (HFC + POE)
Elastomers Seals and Leaks
Myth • There is a belief that introducing POE oil into a system causes a breakdown of seal material causing leaks Fact • When an HVACR system is charged the rubber elastomers seals absorb refrigerant and swell. • When you remove the HCFC refrigerant the elastomers will shrink to near their original size.
• When you re-charge the system with an HFC, the absence of Chlorine, reduces the absorption rate and the seal will not swell at the same rate. • The retrofit process must include replacing all elastomers and o-ring
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Elastomers Seals and Leaks
Schrader Cores and Caps
Open Drive Shaft Seals
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Elastomers Seals and Leaks
Evaporator Pressure Regulator
Heat Reclaim Valve
Solenoid Valve 14
Refrigerant Blend Characteristics • All Blended (R400 Series) Refrigerants have some measure of glide. Glide is the temperature range in which evaporations or condensing occurs. • PT Charts reference both Bubble and Dew points • Dew is used to measure Superheat • Bubble used to measure Subcooling
Refrigerant Blend Characteristics - Superheat • To determine superheat, use the Dew point value. • Procedure: • Use gauges to determine the pressure at the coil outlet. • Use a thermometer to get the temperature at the same point. • Get the Dew temperature from the Dew column. • Superheat = Actual Temperature – Dew Temperature. • Example: Find the superheat on an R407C system when the pressure at the evaporator outlet reads 80 psig and your surface thermometer reads 45°F. • 80 psig yields ~ 50.7°F (Dew point) • Degree of Superheat = 50.7F – (45°F) = 5.7°F
Refrigerant Blend Characteristics - Subcooling • To determine subcooling, use the Bubble point Value. • Procedure: • Use gauges to determine the pressure at the coil outlet. • Use a thermometer to get the temperature at the same point. • Use the Bubble column temperature. • Subcooling = Actual Temperature – Bubble Temperature. • Example: Find the subcooling on a system using R407C when the liquid line temperature reads 130°F and the liquid line pressure is 300 psig. • 300 psig yields ~ 120.4°F Bubble point • Degree of Subcooling = 130°F – 120.4°F = 9.6°F
Refrigerant Blend Characteristics - Evaporator • Looking at the Evaporator at 80 lbs • Liquid would enter the Evaporator at Bubble Point 39.9F • A combination of liquid and Vapor would exist until it reached the Dew Point of 50.7F • Your actual Evaporator Temp will be near the Average 45.3 • Always use the Average value for temperature controlled set points, and equipment selections. • Assuming you wanted a 55f discharge air, and a standard 10f what would you do …?
Refrigerant Blend Characteristics - Condenser • Looking at the Condenser at 300 lbs
• Vapor would enter the Cond. at Dew Point 128.4 F • A combination of liquid and Vapor would exist until it reached the Bubble Point of 120.4F • Your actual Coil temp will be near of the average 124.4F • Always use the Average value for temperature controlled set points, and equipment selection. • Assuming you wanted 125f condensing temperature and a
standard 20f TD What would you do….?
Legislative Changes • Global Warming is now the focus. • Carbon containing CFC, HCFC and HFC are categorized as to High Global Warmers.
• California Refrigerant Management Program took effect in 2012. • Auto Makers and the Aerosols mfg are phasing out of R-134a. • F-Gas Regulations are now in place in Europe. • EPA Considering removal of SNAP approval on R404/R507/R134A. • CFC are being purchased and destroyed for Carbon Credit Value.
Legislative Changes • EU f-gas regulations take effect 1-1-15 • Introduction of a production cap and phase-down schedule for HFC’s • by 2030 they will be at 21% of the 2012 baseline.
•Domestic appliance Ban on HFC’s >150 GWP Jan-2015 • this has pushed them to flammable hydrocarbon refrigerants. • Commercial Refrigeration Ban on HFC’s >2500 GWP Jan-2020. >150 by Jan-2022 • Split System AC Ban on HFC’s > 750 Jan-2025. • They are considering a service Ban, requiring retrofits to gases