“Watt” is the unit of Power with SI unit equal to one joule per second. A Btu (British Thermal Unit) is a unit of heat energy. One  Btu is equal to the amount of heat required to raise the temperature of one pound of water by one degree Fahrenheit. Btu/hr is a unit of Power that determine in estimating the heating or cooling capacity of the system.

“Floc point” is the temperature at which waxy materials in the oil separate from the refrigerant. This can cause problems in the refrigeration system such as the wax blocking filters and restricting flow resulting in reduced efficiency, increased wear & tear, and system failure.

Scroll compressors are positive displacement compressors (compress the refrigerant by physically reducing its volume) consisting of .rotors mounted on a common shaft. These rotors rotate in opposite directions creating a spiral-shaped compression chamber. The suction vapors are drawn into the compression chamber and compressed as the rotors move closer together. They are used in air conditioning and refrigeration systems because of their compact size, quiet & reliable operation and low maintenance

Refrigerant enters the evaporator as a low-pressure, subcooled liquid. As it flows through the evaporator, it absorbs heat from the surrounding air. If the heat load on the evaporator increases, the evaporator absorbs more heat, which causes the refrigerant to evaporate faster

A halide leak detector is a device used to detect refrigerant leaks in the refrigeration system. A halide leak detector should not be used near flammable material because it can create a fire hazard.

Yellow Hose ——> Vacuum pump or refrigerant recovery cylinder
BlueHose      ——>Low side of the system
Red Hose     ——> High side of the system

The higher the ambient temperatures, the lesser will be the evacuation time of the refrigerants from the system. This is because the refrigerant will vaporize more easily at higher temperatures. As the temperature increases, the refrigerant in the system vaporizes and takes up more space. This increases the pressure in the system which forces the refrigerant out of the system more quickly. The evacuation time of the refrigerant also depends on the type of refrigerant used, amount of refrigerant, ambient temperature, size of the system, and vacuum pump used.

The sight glass is present at the liquid line in the refrigeration cycle. The liquid line is the pipe that carries the liquid refrigerant from the condenser to the expansion valve. The sight glass is a transparent tube that allows the technician to see the flow of refrigerant through the line. This helps the technician to diagnose problems with the refrigeration system.

An oil separator is typically located in the compressor discharge line of a refrigeration cycle. The oil separator is a device that removes oil from the refrigerant as it flows from the compressor to the condenser. It helps in preventing clogging the condenser, damaging the compressor, and interfering with the expansion valve

Latent heat is the heat that is required to change the state of a substance without changing its temperature.  It is the heat that is absorbed or released by a substance during a phase change, such as melting, vaporization, or condensation.

Resistance is the opposition to the flow of electric current. It is measured in ohms. The higher the resistance, the less current will flow into the circuit. It depends on the type of conductor material, length of the conductor, cross-sectional area of the conductor, and temperature of the conductor.

Propane and butane are heavier than air. Propane and butane are about 1.55 and 2.08 times denser than air, respectively. At standard temperature and pressure, propane and butane are both denser than air. However, as the temperature of these gases increases, their densities will decrease and eventually become less than the density of air.

Gas valves are controlled by a thermostat or other control device. When the thermostat calls for heat, it sends a signal to the gas valve, which opens and allows gas to flow to the burner. Gas valves operating in furnaces, boilers, and other larger appliances will have a typical voltage rating of 24 volts.

In the direct-vent venting system,  the combustion gases are exhausted directly to the outdoors through a pipe that is attached to the furnace. Direct-vent venting systems are becoming increasingly popular because they are more efficient and safer than other types of venting systems.

High-pressure boilers typically operate at 150 psi and above and are used in a variety of applications, including industrial, commercial, and power generation. They have the advantage of higher efficiency, lower footprint, and lower operating costs.

1 Watt is equal to approximately 3.412 Btu/hr.
1 kWh = 1000 watts
1 kWh = 3412 Btu/hr