7.2 Type I Recovery Requirements

7.2 Type I Recovery Requirements

Recovery requirements for small appliances differ from those for larger systems. Understanding these specific requirements is essential for passing the Type I section of the EPA 608 exam.

Recovery Requirements Based on Compressor Status

The recovery requirements for Type I appliances depend on whether the appliance's compressor is functional:

Recovery Methods for Small Appliances

System-Dependent (Passive) Recovery

System-dependent recovery uses the appliance's own pressure or compressor to move refrigerant into the recovery container:

Method 1: Using the appliance compressor (if operational)

1. Connect recovery equipment to the appliance process tube or service port
2. Run the appliance compressor to push refrigerant into the recovery container
3. Continue until 90% recovery or 4-inch vacuum is achieved

Method 2: Using system pressure (if compressor not operational)

1. Connect recovery equipment to the appliance
2. Allow refrigerant to migrate from the appliance to the recovery container based on pressure differential
3. May require heating the appliance and/or cooling the recovery container
4. Continue until 80% recovery or 4-inch vacuum is achieved

Self-Contained (Active) Recovery

Self-contained recovery uses a dedicated recovery machine with its own compressor:

1. Connect the recovery machine to the appliance
2. The recovery machine's compressor actively pulls refrigerant from the appliance
3. Works regardless of whether the appliance compressor is functional
4. Generally faster and more thorough than system-dependent methods

Accessing Refrigerant in Small Appliances

Small appliances often lack service valves, so technicians must create access points:

• Process tube: A small tube crimped or soldered shut during factory manufacturing — can be opened by piercing or cutting
• Line tap valve (piercing valve, saddle valve): Clamps onto the refrigerant line and pierces it to create an access point
• Schrader valve: If present, provides a standard service connection

Best practices:

• Install a line tap valve on the compressor process tube when possible
• After recovery, the pierced area must be sealed (soldered, brazed, or capped)
• Ensure the access point is on the correct side of the system for effective recovery

Releasing Trapped Refrigerant

When using passive recovery and the compressor is non-operational, refrigerant can become trapped in the compressor oil (refrigerant is miscible with oil). Techniques for releasing trapped refrigerant include:

1. Apply heat to the compressor shell using a heating blanket or heat gun (NOT an open flame)
   • Warming the oil reduces its ability to hold dissolved refrigerant
   • The refrigerant vaporizes and can then be recovered
2. Gently tap the compressor bottom with a rubber mallet
   • Creates agitation that helps release dissolved refrigerant from the oil
3. Allow additional time for refrigerant to migrate out of the oil
4. Run the recovery machine in repeated short cycles to pull additional trapped refrigerant

Disposal of Small Appliances

Before disposing of any small appliance, the refrigerant MUST be recovered:

• The last person in the disposal chain is responsible for ensuring recovery was completed
• Scrap metal dealers and recyclers who accept refrigerant-containing appliances must have a Section 608 certified technician recover refrigerant, OR verify that recovery has already been completed
• Documentation of recovery should accompany the appliance through the disposal chain

For the Exam: Key numbers: 90% with compressor running, 80% with compressor not running, 4-inch Hg vacuum for both. Heating the compressor with a blanket (never an open flame) helps release trapped refrigerant from oil. System-dependent recovery is limited to 15 lbs.