Blue Star Assembly Engineer Interview Questions and Answers

AC works by transferring heat from inside a building to outside, using a refrigeration cycle.

• AC units contain a refrigerant that absorbs heat from indoor air and releases it outside.

• The refrigerant evaporates at low pressure and temperature, absorbing heat in the process.

• The refrigerant is then compressed, raising its temperature and pressure, before releasing the heat outside.

• The cycle continues to maintain a comforta...read more

The gases in an AC unit typically include refrigerant gases such as R-410A or R-22.

• Refrigerant gases are used in AC units to absorb and release heat in order to cool the air.

• Common refrigerant gases used in AC units include R-410A (Puron) and R-22 (Freon).

• These gases circulate through the AC system in a continuous cycle to facilitate the cooling process.

The indoor unit and outdoor unit coils are typically made of metals such as copper, aluminum, or a combination of both.

• Common metals used in coils are copper and aluminum

• Some coils may be made of a combination of copper and aluminum for better heat transfer

• Other metals like steel may also be used in some cases

The copper pipe between indoor and outdoor units is covered by foam and white roll for insulation and protection against external elements.

• The foam provides insulation to prevent heat loss or gain during the refrigerant transfer process

• The white roll acts as a protective layer to shield the copper pipe from external damage such as UV rays, moisture, and physical impact

• The insulation and protection help maintain the eff

Using two adjustable spanners to tighten a flare nut in a union can lead to it loosening due to uneven pressure distribution.

• Using two adjustable spanners can result in uneven pressure being applied to the flare nut

• This can cause the flare nut to become loose over time

• It is recommended to use a proper flare nut wrench for tightening flare nuts in unions

The AC may be cut off due to various reasons such as power outage, malfunctioning components, or scheduled maintenance.

• Power outage: AC will be cut off if there is a power outage in the building.

• Malfunctioning components: If any part of the AC system malfunctions, it may be cut off to prevent further damage.

• Scheduled maintenance: AC may be cut off temporarily for routine maintenance to ensure optimal performance.

The tools used in One AC installation include screwdrivers, pliers, wire strippers, and a multimeter.

• Screwdrivers are used to tighten or loosen screws during installation.

• Pliers are used for gripping and bending wires or components.

• Wire strippers are used to remove insulation from wires.

• A multimeter is used to measure voltage, current, and resistance in the AC system.

Types of AC include window AC, split AC, central AC, portable AC, and ductless mini-split AC.

• Window AC: typically installed in a window and cools a single room

• Split AC: consists of two units - one indoor and one outdoor - connected by refrigerant lines

• Central AC: cools the entire house through a system of ducts

• Portable AC: can be moved from room to room and does not require installation

• Ductless Mini-Split AC: similar t

Vaccuuming the AC indoor helps remove dust, dirt, and debris that can accumulate and block airflow, leading to inefficient cooling and potential damage to the system.

• Vaccuuming helps improve the efficiency of the AC system by ensuring proper airflow.

• It helps prevent blockages caused by dust and debris, which can lead to overheating and system malfunctions.

• Regular vaccuuming can prolong the lifespan of the AC unit and r...read more

Coils are often used in gas leaks to detect the presence of gas due to their sensitivity to changes in electrical resistance.

• Coils are commonly used in gas leak detectors because they can detect changes in electrical resistance caused by the presence of gas

• The coil is typically part of a sensor that is designed to trigger an alarm or signal when a gas leak is detected

• The coil may be connected to a circuit that measures...read more