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John Hill. Technical Training. john.hill@goodmanmfg.com 713-861-2500 Ext.907. TECHNICAL SUPPORT. 888-593-9988. NAECA. National Appliance Energy Conservation Act January 23, 2006 Minimum SEER – 13 Previously – 10 Minimum HSPF 7.7 Previously – 6.8. Montreal Protocol.
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John Hill Technical Training john.hill@goodmanmfg.com 713-861-2500 Ext.907
TECHNICAL SUPPORT 888-593-9988
NAECA • National Appliance Energy Conservation Act • January 23, 2006 • Minimum SEER – 13 • Previously – 10 • Minimum HSPF 7.7 • Previously – 6.8
Montreal Protocol • Montreal Protocol on Substances that Deplete the Ozone Layer • No Production of R-22 Equipment in 2010
Montreal Protocol • CFC Phase Out (R-12) • 1991 – 100% • 1996 – 0% • HCFC Phase Out (R-22) • 1995 – 100% • 2020 – 0%
Service Valves • Service valves located at 90o angle. • Unobstructed access to gauge ports. • More room to maneuver tools.
Access to the Control/Electrical Panel • Two screws to remove the outside cover • Removable Panel • Contactor with lug connectors • Ground with lug connector • Room for field installed accessories
Super-heat and Sub-cooling charts • The super-heat and sub-cooling charts will be posted on the back side of the control door.
Access to the Condenser Coil • The 2006 units will come with 4 independent louver panels. They are easy to remove for quick accessibility to the condenser coil.
INSTALLATION TIPS • NO CAPILLARY TUBE EVAPORATORS • LINE SETS WITH ¼ LIQUID 5/8 SUCTION MUST BE LESS THAN 25 FT. IN LENGTH • EVAPORATORS WITH FLOWRATORS CHANGED TO THE PISTON SUPPLIED WITH NEW CONDENSORS • WHEN CHARGING SYSTEM USE SUPERHEAT OR SUBCOOLING METHOD • HEAD PRESSURE WILL BE LOWER THAN 10 SEER SYSTEM • HEAT PUMPS REQUIRE COMPLETE SYSTEM CHANGE OUT
INSTALLATION TIPS USING A 13 SEER CONDENSER WITH A 10 SEER OR LESS EVAPORATOR MAY DEGRADE CAPACITY BY 6% TO 10%. IN APPLICATIONS WHERE CAPACITY IS MARGINAL, IT MAY BE NECESSARY TO INCREASE THE CAPACITY OF THE CONDENSOR BY ½ TON. IT IS IMPORTANT THAT WHEN DOING THIS , THAT THE ELECTRICAL SERVICE IS ADEQUATE FOR THE LARGER CONDENSOR. IT MAY ALSO BE NECESSARY TO INCREASE THE SIZE OF THE REFRIGERATION LINE SET.
R-22 Phase-Out Timeline % $20/lb 100 R-22 Cost Montreal Protocol/US Phase-Out 65% % 1996 CAP $10/lb 50 35% EU Phase-Out 10% $2/lb 0 1999 2004 2010 2015 2020 No New Equip. US No New Equip. EU
Why R-410a? • R-22 Alternatives • R-134a • R-407c • R-410a • R-417b • Propane • Carbon Dioxide
US New Refrigerant Transitions R-134A Screw Chillers60- 500 Ton R-22 R-410A R-407C Commercial5 to 100 Ton R-22 R-410A R-410A Residential1.5 to 5 Ton R-22 1990 1995 2000 2005 2010
Back Seat Service Valves • All “R” series models equipped with back seating service valves • RVP February 2003
R-410 Facts • Ozone friendly- No Chlorine • Replacement for R-22, NOT a drop in! • Higher Pressure Range-50 to 75% higher than R-22 • Requires Special Lubricants
Components that needed Redesigned for R410A • Compressor • Condenser coil • Filter Drier • Expansion device • Evaporator • Pressure switches
Compressors • Copeland ZRS and ZPS Compressors • We will get further into these later in the program
Pressure Switches • Pressure Switches have to be at higher settings • Low Pressure R410a=50psi • High Pressure R410a=610psi
Line Sets Line Sets New Line Sets are always recommended, but required if: • The previous system had a compressor burn out. • The existing line set has oil return traps. • The existing line set has been open to the atmosphere for an extended time. • The existing line set is larger than or smaller than the recommended line size for the Amana R-410a system. • The existing line set is damaged, corroded, or shows signs of abrasion/fatigue.
Special Tools Required • Differences in Saturation Pressures between R22 and R410a affects many of the tools the Technician must use when Charging and Servicing an R410A system. • Some of the tools used on R22 systems may be unacceptable for use on R410a systems.
Manifold Gauge Set • Standard Gauges and hoses cannot be used safely with R410a. • The High Side gauge should have a range of zero to 800psi. • The Low Side gauge should have a range from 30 inches vacuum to 250psi. • The Low Side gauge should also have a 500psi retardation feature. This slows the movement of the gauge needle at higher pressures.
Refrigerant Hoses • The 600psi rating of standard hoses is NOT adequate for R410a. • Hoses need to be rated for a 800psi working pressure, with a 4000psi bursting rating. • 5 to 1 safety margin is necessary to prevent dangerous hose ruptures.
Vacuum Pumps • Pumps used with CFC and HCFC charged systems may also be used on R410a systems as long as the pump is capable of attaining a vacuum of level of at least 250 Microns.
Leak Detectors • Leak detectors should be checked to see that they are designed to properly detect R410a. • The detector should have adjustable sensitivity to allow leaks to be pinpointed in areas where background vapor might cause false readings.
Two Stage Compressor • Features: • High Efficiency • Quiet Operation • Scroll Technology • No Shut-Down to Shift Capacity
Copeland Scroll™ UltraTech Two-Stage Modulation Scheme Bypass Ports Closed Bypass Ports Open 100% Capacity 67% Capacity
R-410a • It’s a Blended Refrigerant. • 50% R-32 and 50% R-125. • This blend is a near-azeotrope, not a true azeotrope like R-502. • A true azeotrope is a mixture that maintains its composition through both the liquid and vapor phase.
R-410a • For a near-azeotrope, the individual refrigerants evaporate or condense at different temperatures. • The differences between these boiling points with mixed refrigerants is called “ TEMPERATURE GLIDE”
R-410a • When temperature glide is high the refrigerants can separate during evaporation or condensation. • This changes the composition of the resulting vapor and liquid. • This separation is called: “FRACTIONATION”
R-410a • Fractionation is very low. • R410a does not significantly separate in the system and the composition of the refrigerant has very minor changes if a leak occurs. • But the fact that some fractionation occurs, means that charging techniques must be adjusted. • The temperature glide of R410a is very low, thus it acts very much like a single refrigerant.
R-410a • Another significant difference between R410a and R22 is its saturation pressure range. • R410a has a higher pressure range curve than R22. • Remember, R410a is a near azeotrope that is subject to some fractionation. At any specific temperature it has a higher vapor pressure when saturated.
Cylinders • Most R410a cylinders have an internal dip tube which allows the feeding of liquid when the cylinder is in an upright position. They must be inverted for for vapor flow. • Color is rose(pink). • The cylinder has to have minimum cylinder pressure requirement of 400 psig rating (DOT 4B400 or DOT 4BW400)
Lubrication • The chemistry of R410a makes it incompatible with mineral based lubricants. • Mineral oils typically used with R22 has relativity low Miscibility with with R410a. • Miscibility is the ability of an oil to dissolve uniformly in refrigerant in either the liquid or vapor state.
Lubrication • The preferred lubricants are the Polyolester or ester based oils. • Commonly known as POE oils. • POE oils are miscible with with any mineral oil traces that might be in the system. • While miscible, it is very important to remove as much mineral oil, particulates, and moisture from existing line sets as possible.
Lubrication • The POE oils are more Hygroscopic than mineral oils. • This means that they absorb moisture very rapidly. • Exposure to the atmosphere must be limited. • The oil will break down into acid and alcohol • Keep the system closed
Lubrication • Any moisture absorbed by into POE oils cannot be removed with a vacuum pump-Only a new drier will work! • Break a recovery vacuum with Nitrogen! • Keep all systems closed until any component replacements are ready for installation.
Brazing • Should be using at least 2% silver alloy • Always wear glasses and gloves. • Always purge with nitrogen when brazing. • Protect the service valves with wet rags or heat sink material. • Scale will get you with POE oils.
Recovery • Yes, you still have to recover the refrigerant. • R410a does not readily biodegrade, care should be taken to avoid any releases to the environment. • The recovery machines used for R410a must be designed to prevent cross contamination between oils and refrigerants.. • Use machines certified for use with R410a.
Recovery • Preferred type is an oil-less compressor model with a pump down feature for removal of all refrigerant from the machine after each use. • If an oil bearing compressor is used, the machine should be restricted to R410a refrigerant. The machine must use ester based oil.
Charging • Charge through the suction side of the system. • Use a commercial-type metering device in manifold hose to allow liquid to vaporize. • Follow your typical sub-cooling and superheat procedures to arrive at the correct charge.