EPA 608 Type 2 Chapter 8 (Take full course for free)
In this module, we will discuss the pieces of equipment used for the recovery process. We will also discuss a few processes to be done before starting refrigerant recovery. Skip to quiz!
1. Recovery Equipment
The main pieces of equipment necessary to perform refrigerant recovery from any system are:
Recovery Machine
Recovery Tank
Digital weighing scale
Low-loss fittings and gauges
A recovery machine contains a compressor to suck out the refrigerant during recovery. There are a few different types of recovery units; two of which we will be discussing here:
Hermetic Recovery Units
Water-Cooled Recovery Units
Recall that a hermetic compressor has all the components in a single shell. A hermetic recovery machine uses a hermetic compressor — the compressor motor, when working, produces a lot of heat.
A deep vacuum in a system is very close to zero pressure. Drawing a deep vacuum means that minimal refrigerant is left in the system, which needs to be sucked out.
Hermetic recovery machines depend on the flow of recovered refrigerant to cool it down. When drawing a deep vacuum, the compressor motor overheats as there is little refrigerant flow to cool it down. This overheating is a drawback of hermetic units.
A water-cooled recovery unit uses a condenser coil that cools down the recovered vapor refrigerant and converts it into a liquid. The recovery unit’s condenser coil is similar to the condenser coil in a refrigeration appliance.
Local municipal water supply is continuously passed over the condenser coils to cool it. A water-cooled recovery unit is generally used to recover large amounts of refrigerant.
Recall that recovery hoses and gauges are connected to the appliance for purposes like recovery, evacuation, and troubleshooting. All pieces of equipment used for any such purposes and manufactured after November 15, 1993, must be equipped with low-loss fittings.
Low-loss fittings minimize the loss and venting of refrigerant fluid while connecting and disconnecting the hoses to the appliances’ service valves. Self-sealing connectors and hand valves are few types of low-loss fittings.
Self-sealing connectors only require screwing or unscrewing of the cap and no force to connect them to the appliances’ service valves. Similarly, hand valves only require the technician to turn a valve.
Note that it is not necessary to report the purchase of any recycling and recovery equipment to the EPA.
2. Processes Before Recovery
Before starting with the recovery process, a few steps are related to the recovery equipment that should be followed.
Before transferring the refrigerant into an empty refrigerant cylinder, it is necessary to evacuate the cylinder first. It is because of the possibility that the empty cylinder might have outside air filled in it. Recall that air is non-condensable, and we want to avoid mixing air with the refrigerant.
All recovery machines have a filter at their inlet used to filter out the solid contaminants present in the refrigerant if any. After recovery, the filter has traces of the refrigerant trapped inside it.
Recall that mixing of two refrigerants is prohibited. Before starting recovery for a new appliance, the recovery machines’ filter should be changed. It is to avoid mixing of the two refrigerants.
3. Conclusion
In this module, we discussed the pieces of equipment used for the recovery process. We also learned about a few processes to be done before starting refrigerant recovery.
Question #1: A hermetic recovery machine when drawing deep vacuums will;
Run faster than other recovery units
Overheat due to reduced flow of refrigerant through the compressor.
Cause high compression of recovered refrigerant.
Make the oil used in hermetic compressor to become highly viscous.
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When drawing a deep vacuum, the hermetic compressors’ motor overheats as there is little refrigerant flowing through it to cool it down.
Question #2: During refrigerant recovery, local municipal water supply is used to cool the;
Water-cooled chillers.
Hermetic recovery unit.
Water-cooled recovery unit.
Deionized water recovery unit.
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Local municipal water is continuously passed over the condenser coils of a water-cooled recovery unit during recovery.
Question #3: Self-sealing connectors and hand valves are used because they;
Minimize the chance of an explosion.
Minimize refrigerant mixing with the refrigerant oil.
Minimize refrigerant release when hoses are connected and disconnected.
Prevent vapor lock during liquid transfer.
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Self-sealing connectors and hand valves are a type of low-loss fittings.
Low loss fittings minimize the loss and venting of refrigerant fluid while connecting and disconnecting the hoses.
Question #4: What should be done before transferring refrigerant to an empty cylinder?
The refrigerant should be chilled.
The refrigerant should be mixed.
The cylinder should be heated.
The cylinder should be evacuated.
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Before transferring refrigerant into an empty cylinder, it should first be evacuated to remove the non-condensable gases from the refrigerant tank.