10/4/2013. The Changing State of Refrigerants

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1 10/4/2013 The Changing State of Refrigerants

2 Refrigerant Chemistry CFC = Chlorofluorocarbon Rapid phase-out Stopped U.S. production in 1996 R-11, R-12, R-113, R-114, R-500, R-502 HCFC = Hydrochlorofluorocarbon Slower, staged phase-out U.S Product/Imports will stop in 2020, (2030 for R123) R-22, R-123, R-124, R-142b R-401a,b R-402a,b, R-408a, R-409a, R-414b, R-416a HFC = Hydrofluorocarbon No U.S. phase-out planned at this time. R-134a, R-143a, R-152, R-125, R-32, R-404a, R-407a,c,f R-410a, R422a,b,c,d R-427a R /4/2013

3 US HCFC R-22 Phase-Out Plan 2003 US restricts R-22 Imports & Exports. HCFC R-141b phased out % Reduction in R-22 production and import Effective Reduction was amended from 65 to 75% 100% 65% 2010 No New R-22 Equipment Allowed Effective Annual 10% step-down Effective EPA Announced a Immediate 45% cut 35% 25% Effective EPA Rescinded Announced the a Immediate % Cut cut 10% 0 Year % Reduction 2020 No HCFC Product. 10/4/ SEER

4 Refrigerant Blend Basics Most all Refrigerant Blends are a mixture of some or all of the following components R-32 HFC R-125 HFC R-134a HFC R-143a HFC R-200 Series Hydro Carbon (Propane) R-600 Series Hydro Carbon (Butane) The mixture and percentage of each component varies depending on the blend and with (R290/R600) used solely to promote oil return in Mineral Oil systems Each manufacture has a vested position in one or more of the components and they Buy or Sell to each other as needed. 10/4/2013

5 10/4/2013 Your HFC Choices

6 10/4/2013 Low Temperature R22 Replacements

7 Medium Temperature R22 Replacement 10/4/2013

8 High Temp - AC R22 Replacement

9 Why all this talk about Oil? Proper Oil Return is a critical for any Refrigeration or AC System. Miscibility between the refrigerant and the oil ensures the lubricant stays where it belongs ( in the Crankcase). System design and operating temperature plays a key role If a system has oil return issues with R22, changing refrigerants will only make it more pronounced. Generally oils becomes trapped in the receiver, or is logged in the evaporator and low side piping. (Oil is harder to move at low temperature) Oil logging not only is bad for the compressor but can have a significant impact on the performance of the system. Oil acts as an insulator and inhibits heat transfer. An oil logged evaporator will act similar to an iced coil

10 More talk about Oil? In the early days Multiple Oil Changes were recommended. You must get +99% of the residual oil out Most felt the change was necessary because the oils were not compatible. This was never the case. Some refrigerants claim to be no-oil-change solutions, but in most cases, system performance and compressor life are impacted. POE Oil is very Hydroscopic so Moisture Management is very important. A Vacuum Pump will not pull sufficient moisture from the system, so use a properly sized liquid line drier. POE Oil is a very good solvent and can cause issues in older, poorly maintained systems. Now it is widely agreed that only percentage of POE is required to ensure proper oil return.

11 Seals and O-Rings Rubber (Elastomers) Seals and O-Rings all absorb refrigerant. HCFC s are absorbed more readily - Causing a greater Swell Rate. When the HCFC is removed, the seals contract to near there normal size. HFC s are not absorbed at the same rate so the seals will not swell as much and can cause leaks. All Elastomer seals and O-Rings must be replaced. EPR s (SORIT) Older Solenoid Valves (Wolverine seals are ok) Heat Reclaim Valves Shaft Seals on Open Drive Compressor Schrader Cores and Seal Caps Some Ball Valves Mueller This is true with ALL HFC Refrigerants NO DROP-INS

12 Liquid Receivers and 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 it is 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

13 Setting up Controls for Blended Refrigerants To measure Subcooling us Bubble Point* *sometimes referred to as Liquid Pressure To measure Superheat use Dew Point** ** sometimes referred to as Vapor Pressure

14 Measuring Superheat Refrigerant is in superheated vapor state at the end of the evaporator. To determine superheat, use nearest saturated state (dew point) in your P-T chart Procedure: Use gauges to determine the pressure at the coil outlet, and a thermometer to get the actual temperature at the same point. Get the Dew temperature from the Dew column Superheat = Actual Temp Dew Temp To find the superheat on a system using (407F) evaporator outlet pressure reads 24 psig surface thermometer reads 10 F psig yields ~ 0 F (using Dew point) Degrees of Superheat = 10 F (0 F) = 10 F

15 Measuring Subcooling Refrigerant will be in liquid state at the end of the condenser. To determine subcooling, use the nearest saturated state (Bubble point) in your P-T chart Procedure: Use gauges to determine the pressure at the coil outlet, and a thermometer to get the actual temperature at the same point. Get the Bubble temperature for the bubble column Subcooling = Actual Temperature Bubble Temperature Find the amount of subcooling on an R407F system liquid line pressure is 215 psig. liquid line temperature reads 80 F 215 psig yields ~ 90 F (using Bubble point) Degree of Subcooling = 90 F - 80 F = 10 F

16 Control Set Points The operating coil temperature for single component refrigerants is found in the P-T chart. For blended refrigerant - with glide, you want to use the average of the Dew and Bubble values for the given pressure. To find the average condensing temperature for an R407F system, where the outlet reads 215 psig. Find ~215psig in Bubble column: 90 F Find ~215psig in Dew column: 98 F The average coil temp = (90+98)/2 = 94 F To find the average evaporator temperature for an system, where the outlet reads 10 psig Find ~10 psig in Bubble column: -30 F Find ~ 10psig in Dew column: -20 F The average coil temp = (-30+(-20))/2 = -25 F Using solely dew or bubble temperatures may reduce system performance

17 Most Popular Refrigeration Solutions Good Better Best Characteristics R422D R407A R407F System Compatibility Lubricant Compatibility Component Compatibility Near Drop-In for systems without a liquid receiver Works with Mineral AB or POE Oil All Elastomer/o-rings should be replaced Close capacity match with some system change required Requires a % of POE Oil All Elastomer/o-rings should be replaced Closest capacity match with some system change required Requires a % of POE Oil All Elastomer/o-rings should be replaced Expansion Device Compatibility Capacity Relative to R22 No TXV change. Fixed orifices should be evaluated No TXV or Fixed orifice change needed 89% at +20 f 103% at +20 f 95% at -20 f No TXV or Fixed orifice change needed 107% at +20 f 101% at -20 f Environmental & Safety Factors 2700 GWP A1/A1 Rated 2012 GWP A1/A1 Rated Lowest 1825 GWP A1/A1 Rated

18 Popular Air Conditioning Solutions Good Better Best Characteristics R422B R422D - R438A R407C System Compatibility Lubricant Compatibility Component Compatibility Near Drop-In for systems without a liquid receiver Works with Mineral AB or POE Oil All Elastomer/o-rings should be replaced Near Drop-In for systems without a liquid receiver Works with Mineral AB or POE Oil All Elastomer/o-rings should be replaced Closest capacity match with some system change required Requires 20 % of POE Oil All Elastomer/o-rings should be replaced Expansion Device Compatibility No TXV change. Fixed orifices should be evaluated No TXV change. Fixed orifices should be evaluated No TXV or Fixed orifice change needed Capacity Relative to R22 90% at +105 f cond. 94% at +105 f cond. 96% at +105 f cond. 99% at +105 f cond. Heat Pump Considerations Lower discharge temperature may impact heating performance Lower discharge temperature may impact heating performance Similar discharge temperature and heating performance

19 AC Retrofit Considerations and Check list Always use proper tools and safety equipment. Identify and correct any system deficiencies. Record baseline system data. Suction and Discharge Pressure Liquid Sub Cooling and Suction Superheat Temps Compressor Amps Disconnect electrical power. Evacuate the system and weigh the R22 Charge. Replace Elastomers Rubber o-rings and seals. Schrader Cores and Seal Caps Shaft Seals on Open Drive Compressor Older Solenoid Valves (Wolverine seals are ok) not typical on AC System.

20 AC Retrofit Considerations - Continued Change to or add POE lubricant if required. Replace liquid line filter driers and suction filters. Perform a system leak check. Charge the system with replacement refrigerant blend. Start at about 95% of the recovered R22 charge. Charge blended refrigerants in a liquid state using a throttling valve. On Expansion Valve systems us the sub cooling method and refrigerant bubble point. On Fixed Orifice systems use the superheat method and the refrigerant dew point. Allow the system to stabilize and adjust the charge as needed. Label the system showing the new refrigerant and oil.

21 10/4/2013 What s on the Horizon HFO Refrigerant Blends

22 10/4/2013 For more info go to www/rsd.net/refrigerantsuite or Call ex 00405