Copper/Brazing
To prevent oxidation (scale) inside the pipe while brazing, you must flow this gas.
What is Nitrogen?
This device drops the pressure of the liquid refrigerant before it enters the evaporator.
What is the Metering Device (or TXV/Piston)?
A vacuum pump's performance is measured in this unit (volume per minute).
What is CFM (Cubic Feet per Minute)?
This is the term for removing refrigerant and storing it in an external container.
What is Recovery?
What should you always do before working on electrical HVAC equipment?
Turn off the power at the breaker.
This is the specific temperature range that distinguishes brazing from soldering.
What is 840°F (450c)?
This component, located after the evaporator, prevents liquid from hitting the compressor.
What is the Suction Accumulator?
This tool is used to ensure a vacuum gauge is reading accurately and the system is leak-free.
What is a Micron Gauge?
Under Section 608, you cannot legally top off a system with this many lbs of charge if it leaks over a certain %.
What is 50 pounds? (For commercial/IPE leak rate rules).
What should you do if you get refrigerant on your skin?
Rinse thoroughly with water and seek medical attention if needed.
This measurement refers to the outside diameter of AC/R copper tubing.
What is Nominal Size (or OD)?
This heat exchanger rejects heat from the refrigerant to the outside air.
What is the Condenser?
This should be done to the vacuum pump oil if it becomes cloudy or dark.
What is Changing the oil?
This is the date after which it became illegal to vent any CFC, HCFC, or HFC.
What is July 1, 1992 (or the general venting prohibition)?
Always use a pressure regulator with a relief valve when connecting to a cylinder of this gas, as its pressure exceeds 2,000 psig
What is dry nitrogen gas?
This process involves heating copper and then cooling it to make it soft and workable again.
What is Annealing?
This valve reverses the flow of refrigerant in a heat pump system.
What is a Reversing valve
This law states that the total pressure of a mixture of gases is the sum of the partial pressures.
What is Dalton’s Law?
This category of refrigerant has the highest Ozone Depletion Potential (ODP).
What are CFCs (Chlorofluorocarbons)?
This ASHRAE safety classification is given to non-flammable refrigerants with low toxicity, such as R-134a
What is A1?
how do you prevent slag from forming while brazing ?
flowing Nitrogen in the pipe
What is a capillary Tube?
a metering device
The high-pressure gauge on a manifold set used for R-410A must be rated for at least this pressure
What is 800 psig?
This AHRI standard specifies the purity level required for used refrigerant to be classified as reclaimed
What is ahri 700
When servicing systems with flammable refrigerants, the system, recovery unit, and recovery cylinder must all be properly connected to this to avoid ignition from an electrical spark
What is ground or grounding?