Licensing Requirements Under section 608(c) of the 1990 Clean Air Act Amendments, “… ( It is )unlawful for any person, in the course of maintaining, servicing, repairing or disposing of an appliance…. to knowingly vent or otherwise knowingly release or dispose of any Class I or Class II substance used as a refrigerant in such an appliance in a manner which permits such substance to enter the environment… “ The Act further establishes that any technician that can be reasonably expected to enter a sealed system during the course of repair of a refrigeration appliance must be certified in refrigerant handling by a Federal EPA approved certification organization.
EPA Penalties A willful release of refrigerants or failure to follow EPA recovery guidelines carries stiff penalties for the technician –$30,000 per occurrence –Up to 5 years jail time EPA offers a $10,000 reward to anyone reporting a violation
Certification Classifications There are 4 certification classifications: Type I- Allows technicians to perform service on refrigeration equipment containing less than 5 lbs. of refrigerant. Type II- Allows technicians to work on refrigeration equipment containing more than 5 lbs. but less than 50 lbs. of refrigerant. Type III-Allows a technician to work on refrigeration equipment containing more than 50 lbs. of refrigerant Universal- Allows a technician to work on any refrigeration equipment, regardless of the amount of refrigerant.
Certification Guidelines Type I or Universal certification is required to work on residential refrigeration appliances. Type II and Type III certifications do not permit working on small appliances. Technicians are required to have valid certification cards on their person anytime that they are performing repairs on a refrigeration system.
EPA Restrictions Purchase of refrigerant is restricted to certified technicians and Section 608(c) certified technicians can only purchase refrigerant in 30 lb. (minimum) containers. Recovery of refrigerants must be accomplished with an EPA approved recovery device. Two types of recovery devices are allowed. –Active- a recovery pump that is able to pull a system into a minimum 4” vacuum. –Passive- a non powered device capable of capturing 80% of the system charge (such Recovery bag)
EPA Restrictions Use of refrigerant recovery bags, such as the Whirlpool Ozone Saver® Bag, is regulated by the EPA. Compliance requires: –The technician must recover a minimum of 80% of the system charge. On a non working compressor, the base of the compressor must be heated and struck sharply with a hammer to free any refrigerant trapped in the compressor oil. –Recovery bags are designed as temporary refrigerant storage devices and should be removed from vans each night. –The bag can only be used 4 times before it is discarded. – The bag must be emptied within 48 hours –Torn or damaged bags must be discarded.
Recovered Refrigerant All Refrigerants must be recovered and reclaimed Mixed refrigerants cannot be reclaimed and must be destroyed –Some refrigerants (R-12, R-134a) have value on the reclaim market. –Every pound we have to destroy not only costs us $3-4 per pound to dispose of but we miss out on the reclaim income that would have been generated
Other EPA Recommendations All leaks should be located and repaired All hoses and manifold gauge sets must utilize low loss fittings
US Department Of Transportation (DOT) Guidelines
Material Safety Data Sheets (MSDS) Technicians are required to carry MSD Sheets for every type of chemical in their truck, including acetylene, oxygen, glues, cleaners and refrigerants. –Technicians should read and follow all recommended safety guidelines when handling refrigerants and other chemicals.
Transportation of Refrigerants and other Compressed Gasses Refrigerant, acetylene, oxygen, nitrogen, etc. are all considered to be hazardous materials by US DOT. Shipping of these containers is highly regulated. –Before shipping any of these items by common carrier, check with the carrier to determine packaging and Bill of Lading requirements. –Air freighting of these items is strictly prohibited. All compressed gasses such as refrigerant, acetylene, oxygen, aerosol and paint cans, etc. must be in DOT approved containers and secured in the van with chains or other significant restraints to prevent containers from falling over, rolling around in the truck, etc.
Transportation of Refrigerants and other Compressed Gasses All cylinder valves should be completely closed and OXY/Acetylene regulators removed whenever a cylinder is being transported All cylinder must completely shut-off with no leaks
Transportation of Refrigerants and other Compressed Gasses The acetylene cylinder must not have been fully closed and a small leak occurred On the Monday morning when the van door was opened, a large explosion took place. Tech suffered damage to his ear drums and face.
Transportation of Refrigerants and other Compressed Gasses Transporting refrigerant in charging cylinders (such as Dial-a-Charge) is not permitted. Charging cylinders must be empty of refrigerant before transporting. Some states go as far as requiring that refrigerant be removed from self sealing hoses on compound gauges. To assure compliance, technicians should be sure to recover refrigerant from gauges before transporting.
Cylinder Safety New refrigerant is packaged in DOT 39 disposable cylinders. When empty, these cylinders must be disposed of properly. After evacuating the cylinder (to 0 PSIG), the valve must be removed. The tank can then be disposed of with other metal waste. Reuse of DOT 39 disposable cylinders (such as storing or carrying compressed air) is illegal and carries a penalty of $25,000 and up to 5 years in prison.
Cylinder Safety Recovered refrigerant can only be stored in DOT approved recovery cylinders (with the exception of temporary storage in a refrigerant recovery bag.) US DOT regulates that recovery cylinders must not be filled beyond 80% capacity. –Many of these tanks are equipped with a ball or float switch that, when connected to a recovery pump, will shut the pump off when the 80% mark on the tank is reached.
Cylinder Safety If the cylinder is not equipped with a ball or float switch, the tank must be weighed prior to each recovery to insure that it can accept additional refrigerant. Cylinders are marked with their empty or tare weight (TW) and water content weight (WC). This represents the total weight of the cylinder and contents when the cylinder is filled to capacity. Sometimes the tank is marked with the tare weight and the “MAX. Gross WT ___ LB.” The max weight, again, represents the total weight of the cylinder when it’s filled to capacity.
Cylinder Safety To insure that the recovery tank is not filled beyond 80%, the technician must determine the max fill level for each tank. To do that, the technician must compute the WC weight (if not listed) and multiply by.8 Example: MAX weight= 23.5 lbs, TW= 10.5 lbs. Max WC weight= 13 lbs. (23.5-10.5) Maximum refrigerant that can be put into tank= 10.4 lbs. (13 lbs. WC X 80%)
Cylinder Safety Overfilled cylinders present a serious safety hazard. Because liquids don’t compress, any rise in temperature can cause an over filled tank to explode. Technicians must avoid overfilling or exposing a tank to extreme temperatures. –In the summer, park in the shade whenever possible –If the truck is equipped with vents, open them –Never use an open flame to heat a refrigerant cylinder
Hydrostatic Cylinder Testing Recovery cylinders must be hydrostatically tested every five years. The last test date will be stamped or embossed on the shoulder of the cylinder. In most cases, the tank will clearly be marked with the first retest date. For example, FIRST RETEST DATE 06 07 RETEST EVERY FIVE YEARS This means that the tank must be submitted for testing prior to June of 2007 and every five years after that (on or before the month of June).
Hydrostatic Cylinder Testing Older tanks may have the date stamped on them in the pattern shown to the right. This stamp indicates the last retest date and the testing organization that completed the test. In this example, this cylinder was last tested on May of 2002 by tester A253. The next retest date, therefore, is May of 2007. A2 0502 53
Technicians carrying tanks that are beyond the required test date must discontinue use of the cylinder immediately. –Filling of cylinders with expired test dates is prohibited. –Any tank that has an expired test date must be submitted to a reclaimer for refrigerant processing and cylinder testing. Hydrostatic Cylinder Testing
Labeling of Refrigerant Cylinders All refrigerant cylinders, both new and recovered, must be properly labeled with their content. –If the recovery cylinder is in its original cardboard carton, there are boxes printed on the carton that allow placing an X or a √ mark next to the type of refrigerant that is being carried. –If out of the carton, most refrigeration supply houses supply stickers and/or tags that can be affixed to recovery cylinders to identify the contents.
Contaminated Refrigerants Normal contaminants, such as air, refrigerant oil and water that are mixed with refrigerants in a recovery cylinder are not an issue. Care should be taken, however, to insure that no other contaminants are added to the refrigerant. If a reclaimer suspects that a refrigerant tank is contaminated with unidentified chemicals, regulations require that the contents of the tank be analyzed and the refrigerant be disposed of. Reclaimers charge a fee for this service.
Mixed Refrigerants Mixing of refrigerants should be avoided. –Refrigerants are considered to be mixed when more than 3% of a second refrigerant is added to the base refrigerant. For example, adding 1 lb of R-22 to a cylinder that contains 20 lbs of R-134a will render the entire tank as mixed. –Mixed refrigerants cannot be easily or economically reclaimed and thus, must be destroyed. Instead of the usual $25 or $30 handling fee for accepting used refrigerant, the price to dispose of mixed refrigerants can exceed $100 per cylinder ($3-4 per pound).
Tracking of Refrigerant Usage and Recovery The Federal EPA has the ability to subpoena refrigerant usage records of an individual and/or a company to compare refrigerant purchases against recovery levels. –Since the minimum recovery level for any system is 80%, a discrepancy between refrigerant purchased and refrigerant recovered could indicate that technicians are not recovering at mandated rates. –Technicians must maintain logs to track refrigerant usage
Refrigerant Tracking Log Technician____________________________________ Customer Last Name Address Serv. Ticket # Refrigerant Oz. Recvrd Refrigerant Oz.Comments RecoveredInstalled Used R-134a R-22 R-12 OtherDrop-in R-134a R-22 R-12 OtherDrop-in R-134a R-22 R-12 OtherDrop-in R-134a R-22 R-12 OtherDrop-in R-134a R-22 R-12 otherDrop-in Directions: Track all refrigerant usage. Place √ next to refrigerant recovered or installed. Use comment area to denote discrepancies between amount used and amount recovered. I.e. System leak, system flat.
Required Equipment Over the next few months, each White Goods technician will be supplied whatever equipment they’re missing to insure they all have: –Scale –R-134a Charging Cylinder –R-134a Manifold Gauge set –Recovery pump –30 lb. recovery cylinder –Electronic Leak Detector –Hand valves (2) –Process tube adapter kit –Pinch off pliers –Recovery Bags (2)
Required Equipment Over the next few months, each “specialty” technician will be supplied whatever equipment they’re missing to insure they all have: –Scale –R-134a Charging Cylinder –R-134a Manifold Gauge Set –CFC Manifold Gauge Set –Micron Gauge –Recovery pump –Vacuum pump –30 lb. recovery cylinder –Electronic Leak Detector –Hand valves (2) –Process tube adapter kit –Pinch off pliers –Recovery bags (2)
Required Equipment Over the next few months, each PTAC** technician will be supplied whatever equipment they’re missing to insure they all have: –Scale –CFC/HCFC Manifold –Vacuum Pump –Micron gauge –Recovery pump –30 lb. recovery cylinder –Electronic Leak Detector –Hand valves (2) –Process tube adapter kit –Pinch off pliers **PTAC techs who also work on White Goods will also carry R-134a refrigerant and related tools
Refrigerant Handling Process Virgin refrigerant –Technicians serviced by land based currier will continue to receive new refrigerant from RPDC –Technicians serviced by air currier must purchase refrigerant locally. (Use Refron facilities when possible to get quantity preferred pricing)
Refrigerant Handling Process Used refrigerant –Technicians serviced by land based currier will return full cylinders to RPC RPC will replace with empty, clean cylinder –Technicians serviced by air currier must find local parts supplier that is willing to accept used refrigerant Work with virgin refrigerant supplier Set up cylinder exchange program
Bag vs. Pump Use recovery pump and tank on all Major Brand refrigeration that –can be swept –uses R-134a Use the bag when servicing systems with –Burnouts –Unknown refrigerant –Drop-in refrigerant
Bag Handling Process Technicians serviced by land based currier –Return bags to RPC with tag identifying contents as Unknown refrigerant R-134a Burnout R-22, MP-39, etc –RPC will replace with empty, clean bag Technicians serviced by air currier –Transfer contents of bag to a cylinder every night R-134a burnouts to R-134a tank R-22 to R-22 tank If enough R-410 is encountered, R-410 to its own cylinder All other refrigerants to “mixed refrigerants” tank
RPC refrigerant handling Each RPC responsible to –Maintain supply of empty tanks on hand to replenish tanks when a full tank is received –Empty bags within 24 hours into appropriate recovery tank R-134a R-22 R-410 All other refrigerants to “mixed refrigerants” tank
Why Change to Sweep Vacuum pumps require constant maintenance –Oil changes every 3 or 4 normal evacuations –After processing every burnout –Dirty oil renders pump incapable of pulling system to required vacuum levels to assure complete dehydration Without ability to gauge dehydration level, there is no way to gauge how effective a vacuum was pulled, even with a well maintained vacuum pump Properly performed sweep superior to deep evacuation with poorly maintained pump or without measuring micron levels in system
Why is proper dehydration important? 0 PSIG 5 PSIG 11.6 in Hg 29.92 in Hg 19.74 in Hg Pressure Affect on Boiling Point of Water 34 84 134 184 234 284 334 26 1014 18 222630 34 PSIG Temperature Atmospheric Pressure 10 PSIG15 PSIG1.4 PSIG Unless system pressure is dropped to 300 microns or less, there is still water left in the system. In order for water to boil at normal room temperatures, system pressure must be dropped below 27” vacuum (About 3,000 Microns or less) Vacuum must be held over system until Micron levels drop below 300 microns Depending on pump conditions, proper dehydration could take several minutes or several hours.
What happens when water is left in the system? Moisture and refrigerant create acids Acids eat away at compressor winding insulation Acids and oil create sludge which plugs cap tubes
Why is proper dehydration even more important with R-134a? R-134a systems do not mix well with with mineral oils and require the use of Ester oils Ester oil are hygroscopic, meaning that they have a great affinity for moisture (actually pull and absorb moisture out of the air) –Ester oils are made from acids that have been dehydrated –When exposed to atmospheric moisture, the oil actually pulls vapor out of the air –The airborne moisture combines with the ester oil and returns it to its original acidic state –Acids eat away at the compressor windings –Acids combine with R-134a to form salts and gels which can plug the capillary tube. Moisture in the system will eventually destroy the compressor (not a matter of if but when)
Why Change to Sweep Sweep has been used in the industry for over 30 years (Maytag, GE, Whirlpool, Sears, Montgomery Wards and a slew of independents) Over the 30 year period, no conclusive proof has ever surfaced that sweep results in any more repeat failures than deep evacuation In fact, laboratory testing has shown that a properly performed sweep is superior to deep evac that is performed with poorly maintained vacuum pump or without an accurate method of measuring dehydration levels in system
Processing R-134a systems R-134a requires dedicated equipment to prevent cross contamination R-134a systems should not be open to the atmosphere for longer than 20 minutes (max) Verify compressor is nitrogen charged Keep plugs in compressor until ready to make final connections to system tubing
Processing R-134a systems Low side leaks –Find and repair leak –Replace compressor and dryer High side leaks –Find and repair leak –Replace drier Compressor burnout –Flush system –Replace compressor and drier
Processing R-134a systems Because of the small system charges of modern refrigerators, accurate charging is critical –On a 5 oz. system, overcharging by ½ oz. results in 10% overcharge Because of energy and cooling capacity issues, it’s better to be slightly undercharged than to be overcharged by any amount.
Affect of Over/Undercharge on 950 BTU Compressor
Problem with using a scale to charge small systems One quarter ounce resolution could undercharge or overcharge a system by as much as 10- 20% (depending on system charge) Unless scale is calibrated on a regular basis, there is no way to determine accuracy of scale Movement of the cylinder during charging changes the reading on the scale and could cause the final charge to be off by as much as 50%
Adding system charge Use Dial-a-Charge for all R-134a products. Charging scales should be used for –Drop-ins –R-22 –To weigh recovery cylinders if cylinder is not equipped with a ball float valve
Approved Sealed System Process Sweep charge is the only approved method of refrigerator and freezer system processing for most product lines –Exceptions PTACS Samsung 4 drawer side by side Refrigerator technicians will need to turn in their vacuum pumps Note: Vacuum pumps will be re-allocated to commercial and specialty techs
Sweep Charge Steps 1.Reconfirm need for the sealed system repair 2.Verify that new compressor is nitrogen charged (should hear a pop when line plug is removed from compressor) 3.Reinstall plugs on compressor to prevent excess air from entering system while old compressor is removed from the system 4.Attach temporary line taps to low side and drier process stubs 5.Attach gauges and recovery pump. Recover refrigerant per pump manufacturer’s recommended procedures
Sweep Charge Steps 6.Cut out and remove old compressor 7.Install new drier 8.Install and plumb new compressor in place (keep compressor tubes plugged until ready to attach to system. This will assure that the system does not stay open longer than the recommended 20 minutes.) 9.Attach process stub adapters to new compressor and drier process stubs 10.Reattach gauges. High and low side hoses should have hand valves attached at end of each hose
Sweep Charge Steps 11.Fill Dial-a-Charge with system charge plus 8 oz. and heat refrigerant until pressure on Dial-a- Charge is 30 lbs. over ambient. Remember to capture refrigerant if bleeding of the cylinder is necessary (EPA reg) 12.Attach Dial-a-Charge to common hose on manifold gauge set. 13.Purge air out of all hoses and pre-charge high side hose with liquid. 14.Charge 4 oz of refrigerant into the system using the hand valve at the end of the high side hose to meter the refrigerant into system.
Sweep Charge Steps 15.Check all joints for leaks with a mirror and electronic leak detector 16.Turn compressor on and allow charge to circulate for 5 minutes 17.Close hand valve at drier 18.Reattach pump and recover sweep charge as a liquid from the drier process stub while the compressor is running. 19.Continue to run recovery pump until the system is down to the pump design pressure (usually around 20 inch vacuum on most pumps)
Sweep Charge Steps 20.Close hand valve at drier and turn off compressor and pump 21.Recheck pressure on Dial-a-Charge to make sure it is still at 30 lbs. over ambient. Reheat if necessary 22.Disconnect pump and reattach Dial-a-Charge to center hose of gauge set 23.Purge hoses and pre-charge high side hose with liquid 24.Using the hand valve, meter system charge into the system Important: Once the charge is added and the hand valve is closed, DO NOT reopen.
Sweep Charge Steps 25.Using pinch off pliers, pinch off the high side process stub. 26.Remove the hand valve and process tub adapter and braise the stub shut 27.Repeat process with low side process stub 28.Check for low side leaks. 29.Restart the compressor and check high side for leaks. 30.Check current draw and feel compressor discharge for heat movement. Check air supply in freezer. If air is cold and current draw is normal, repair was successful.
Processing R-12 Systems with Drop-in Refrigerants MP-39 only approved R-12 substitute –Hot Shot should not be purchased or used due to safety concerns (flammable- contains 6% methane) As with all blends, the sweep and final charges of MP39 must go into the system as a liquid –Requires that refrigerant be heated to 30 lb. over ambient If no heater blanket available for MP-39 tank, tank can be submersed into a partially filled 5 gallon bucket of warm water. Water should be no hotter than your skin can tolerate (125º F) –Charge must go into high side to prevent slugging of compressor Some older refrigerators have direct suction pumps and adding liquid to low side could dump refrigerant into compression chamber