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It's our duty as industry professionals to always do the right thing not only for our customers, but for Mother Earth as well. Reclaim every time.

Ed. note: see sidebar for additional recovery methods.

Allan Smith is President of Air Conditioning Specialists, Portsmouth, VA, and a Trane Comfort Specialist Dealer. He can be reached at 757/558-9122.

Other Recovery Methods

Always use a filter-dryer or particulate filter on your refrigerant recovery unit. It's also important to us an acid core dryer when recovering from a burned out system. Acid and particulate matter will cause damage to your refrigerant recovery system. If you use the appropriate filter on every job, your refrigerant recovery equipment should give you many years of trouble-free service.

The three different recovery methods are: vapor recovery, which is the most common; the push-pull method; and the liquid recovery method, which is gaining in popularity.

The following information describes the steps related to the vapor and push-pull recovery methods. Remember, your system configuration may vary. Check your operation manual to find the proper configuration for your unit.

Vapor Recovery Method

There are 10 steps for proper use of the vapor recovery method:

1. Connect a hose with a low-loss fitting on both ends to the discharge side of the recovery equipment.
2. Connect the other end of this hose to the tank liquid port on the recovery cylinder.
3. Place the recovery cylinder on a scale.
4. Connect a hose from the low-side service port of the HVAC system.
5. Connect the other end of this hose to the center (charging) port of your manifold set.
6. Connect a hose to the low-side of your manifold set.
7. Connect the other end of this hose to the suction side of the recovery equipment.
8. Connect a hose from the tank vapor port to the high gauge on the manifold set. This will allow you to monitor the tank pressure.
9. Close valves on manifold set.
10. Open vapor and liquid valves on the recovery cylinder.
11. Start the recovery system.
12. Allow unit to pull into the appropriate vacuum based on refrigerant type.
13. Close all valves and disconnect from the HVAC system, or begin purge cycle.

Push-pull Recovery method

Use the push-pull method only after you have first checked the configuration of the system being serviced. Here are the questions to ask first:

• Are less than 10 pounds of refrigerant in the system?
• Is the system a heat pump, or one with a reversing valve?
• Will the system allow a solid column of liquid to form?
• Does the system have an accumulator?

If the answer to any of these questions is yes, refer to the vapor or liquid recovery methods.

Otherwise, here are 10 steps to using the push-pull recovery method:

1. Connect a hose from the tank vapor port to the center port of the manifold set.
2. Connect a hose from the low side of the manifold set to the suction side of the refrigerant recovery unit.
3. Connect a low-loss hose from the discharge side of the recovery unit to the low-side service port.
4. Connect the low-loss hose from the high-side service port to the tank liquid valve.
5. Place the tank on a scale.
6. Open valves on recovery cylinder.
7. Start refrigerant recovery machine.
8. Open the low-side valve on the manifold set.
9. Monitor the scale.
10. Switch the unit over to vapor recovery once the scale stops picking up weight.

Ralph A. Vergara is technical sales manager for Ritchie Engineering; rvergara@ritchieengineering.com.