5 Chiller Service Practice and Verification Free Online FlashCards

What does refrigerant recovery do?

Recovery removes refrigerant from an appliance into approved recovery equipment and a suitable recovery cylinder.

How do regulatory recovery evacuation and dehydration evacuation differ?

Regulatory recovery evacuation reaches the required level before opening an appliance or component. Dehydration evacuation removes air and moisture from a repaired, refrigerant-tight circuit before charging.

What recovery level does EPA’s table give for low-pressure appliances?

EPA’s table gives low-pressure appliances a recovery level of 25 mm Hg absolute. This is not a universal target for every chiller or a deep-vacuum dehydration target.

What must technicians do before servicing chiller energy sources?

Apply the site’s lockout/tagout procedure to relevant energy sources and verify isolation before servicing. Chillers can contain electrical, mechanical, thermal, and stored-energy hazards.

How should technicians protect the water side during low-pressure chiller recovery?

Circulate or remove water as required by the equipment procedure to prevent freezing during low-pressure chiller recovery.

Which refrigerant phases must be recovered?

Follow the manufacturer’s connection and operating sequence. Recovering liquid first can improve efficiency, but vapor must also be recovered.

What can pressure rebound after apparent recovery indicate?

A rise may mean refrigerant remains in the system or oil. Continue the prescribed recovery and reassess rather than assuming the system is clear.

What limited recovery exception applies when a leak prevents the normal target?

Where possible, isolate leaking from non-leaking components. Evacuate non-leaking components to the specified level; evacuate leaking components to the lowest attainable level without substantially contaminating recovered refrigerant, not exceeding 0 psig.

What should be checked when pressure-gauge readings conflict?

Confirm the instrument range, calibration status, and connection location, and distinguish gauge pressure from absolute pressure. Record units and do not compare unlike units.

What does a rising pressure during a dehydration standing test mean?

Do not call the circuit dry and tight based only on its initial target reading. Diagnose possible leaks, trapped refrigerant or moisture, valve leakage, or instrument and hose problems.

What compatibility and capacity checks apply to a recovery setup?

Confirm that the recovery unit suits the refrigerant and appliance, and that the approved cylinder is compatible. Monitor cylinder capacity and weight as its manufacturer directs.

What recovery details belong in a service record?

Record the applicable endpoint, instrument and units, readings, waiting and rebound check, and any exception used, along with equipment identification and quantity recovered.