5 Refrigerant Practice and Review Free Online FlashCards

What do the letters A and B indicate in an ASHRAE refrigerant safety group?

A indicates the lower-toxicity class; B indicates the higher-toxicity class.

What should you remember about an A2L refrigerant?

A2L is a flammable classification; for example, R-32 is A2L. A1 does not mean harmless.

What does ozone-depletion potential (ODP) compare?

Ozone-depletion potential compares a substance’s ozone-depletion impact with that of CFC-11.

What is a key environmental and handling concern for CFCs such as R-12?

CFCs such as R-12 deplete ozone. Do not release them; follow applicable recovery and disposal rules.

How should you identify the refrigerant before service?

Use the equipment nameplate and container label to match the exact refrigerant designation and suffix; cylinder color alone is not reliable identification.

How do you confirm which refrigerant a unit is designed for?

Confirm the exact refrigerant and approved charge from the nameplate or documentation. Similar pressure does not make another refrigerant an approved substitute.

What must you check before reading a pressure–temperature chart?

A P–T chart relates a refrigerant’s saturation temperature to its saturation pressure. Select the exact refrigerant’s chart and check whether pressures are psig or psia.

At 40°F, how do the reference-chart pressures for R-410A and R-134a compare?

At 40°F saturation temperature, the reference chart gives about 118.8 psig for R-410A and 35.0 psig for R-134a; these are not operating targets.

Can a P–T chart reading alone confirm correct charge?

No. A chart comparison alone cannot establish correct charge or diagnose a fault; interpret readings using operating conditions and the manufacturer’s diagnostic method.

How should you use bubble-point and dew-point values for a refrigerant blend?

Bubble-point and dew-point values represent different points for a blend that boils over a temperature range. Use the point specified by the manufacturer or service procedure.

What should you do if a leak is suspected in a confined or poorly ventilated area?

Leave the area and follow the site emergency procedure. Do not enter to investigate without authorization and appropriate controls.

What key EPA Section 608 rules apply to covered refrigerant service?

Do not intentionally vent covered refrigerants. Covered stationary-equipment service activities require certification, except apprentices may qualify for an exemption under close, continual supervision by a certified technician.