ESCO A2L - ESCO A2L Refrigerant Leak Detection and Mitigation Questions and Answers

Question 1

A technician is using a portable electronic leak detector to find the source of an A2L refrigerant leak. For maximum safety in a potentially flammable atmosphere, the leak detector itself must be:

Accepted Answer

Rated as intrinsically safe or suitable for A2L refrigerants

Answer

Calibrated for high sensitivity to HFC refrigerants

Answer

Equipped with a long probe to maintain distance

Answer

Able to detect multiple gas types simultaneously

Question 2

In a residential split system, upon the refrigerant detection system (RDS) sensing an A2L leak, which of the following represents the correct and immediate sequence of mitigation actions?

Accepted Answer

Shut down the compressor, activate the circulation fan, and de-energize other potential ignition sources.

Answer

Activate an audible alarm, wait 5 minutes, then start the circulation fan.

Answer

Open all zoning dampers, wait for the refrigerant to clear, then shut down the compressor.

Answer

Immediately reverse the system into the heating mode to burn off the leaked refrigerant.

Question 3

A technician discovers that the factory-installed refrigerant detection system (RDS) in an A2L unit is faulty and must be replaced. According to ASHRAE 15 and UL 60335-2-40, which action is prohibited during this service?

Accepted Answer

Field recalibrating the new sensor's LFL setpoint.

Answer

Replacing the sensor with a manufacturer-approved part.

Answer

Performing a system test after installing the new sensor.

Answer

Ensuring the replacement sensor is for the specific A2L refrigerant.

Question 4

In an A2L system, what is the primary purpose of a mitigation control board (or dissipation board)?

Accepted Answer

To receive a signal from the leak sensor and execute a pre-programmed safety response.

Answer

To increase the efficiency of the cooling cycle.

Answer

To store fault codes for later retrieval by the technician.

Answer

To monitor the refrigerant charge and signal when a top-off is needed.

Question 5

After an A2L refrigerant leak has been detected and the system has entered mitigation mode, the circulation fan runs and dissipates the refrigerant. Once the sensor no longer detects a concentration above the threshold, what does the system typically do?

Accepted Answer

Continue to run the fan for a predetermined period (e.g., 5 minutes) before resuming normal operation.

Answer

Shut down immediately and require a manual reset by the homeowner.

Answer

Send an alert to the manufacturer and wait for a remote reset command.

Answer

Immediately restart the compressor and return to the previous thermostat call.

Question 6

Which of the following is NOT a required mitigation action for a residential high-probability A2L system upon leak detection, according to ASHRAE Standard 15?

Accepted Answer

Activate an external nitrogen purge system.

Answer

Energize the air circulation fan.

Answer

De-energize electric resistance heaters in the ductwork.

Answer

Open any zoning dampers installed in the ductwork.

A technician is using a portable electronic leak detector to find the source of an A2L refrigerant leak.For maximum safety in a potentially flammable atmosphere, the leak detector itself must be:

A technician is using a portable electronic leak detector to find the source of an A2L refrigerant leak.
For maximum safety in a potentially flammable atmosphere, the leak detector itself must be: