EPA 609 Leak Detection & System Diagnosis

Question 1

Which tool is specifically designed to detect refrigerant leaks in an MVAC system?

Accepted Answer

Electronic leak detector

Answer

An electronic leak detector is designed to sense refrigerant vapors and alert the technician to the presence of a leak.

Question 2

What does a manifold gauge reading of 0 psi on BOTH the high and low sides most likely indicate?

Accepted Answer

The system has lost all refrigerant charge

Answer

Zero pressure on both sides means the system has no refrigerant remaining, indicating a total loss of charge due to a major leak or prior incomplete service.

Question 3

UV dye is injected into an MVAC system primarily to:

Accepted Answer

Identify refrigerant leaks under ultraviolet light

Answer

UV dye circulates with the refrigerant and oil, and when a leak occurs, dye seeps out and glows brightly under a UV lamp, pinpointing the leak location.

Question 4

An MVAC system that blows warm air while the compressor is running could indicate:

Accepted Answer

A refrigerant leak causing low charge

Answer

A refrigerant leak reduces system charge, lowering refrigerant flow and heat absorption, so the evaporator cannot cool adequately even though the compressor runs.

Question 5

Frost or ice forming on the orifice tube or expansion valve in an MVAC system usually signals:

Accepted Answer

A restriction or moisture contamination causing a pressure/temperature drop

Answer

A restriction or moisture freeze at the metering device causes a dramatic pressure and temperature drop immediately downstream, leading to ice formation.

EPA 609 - EPA Section 609 Refrigerant Certification Practice Test

EPA 609 - EPA Section 609 Refrigerant Certification Practice Test

EPA 609 Leak Detection & System Diagnosis