What is a b3 refrigerant?
Moreover, Class 3 is for refrigerants that, when tested, exhibit flame propagation at 140°F (60°C) and 14.7 psia (101.3 kPa) and that either have a heat of combustion of 19,000 kJ/kg (8,174 BTU/lb) or greater or a LFL of 0.10 kg/m3 or lower.
What are A1 refrigerants?
A1 refrigerants are identified as having “no flame propagation”1 but common A1 refrigerants such as R-410A or R-22 in use today can burn under the right conditions. Refrigerants are tested to ASTM E681 at a temperature of 60°C but at higher temperatures they can become flammable.
What are the main 3 refrigerant groups?
Types of Refrigerants
- Chlorofluorocarbons (CFCs), including R12. This is known to contribute to the greenhouse gas effect.
- Hydrochlorofluorocarbons (HCFCs), including R22.
- Hydrofluorocarbons (HFCs), including R410A and R134.
How many classes of refrigerants are there?
The three main flammability classifications are class 1, for refrigerants that do not propagate a flame when tested as per the standard; class 2, for refrigerants of lower flammability; and class 3, for highly flammable refrigerants such as the hydrocarbons.
What is an A3 refrigerant?
Refrigerants are classified as below: The vast majority of HFC and HFC/HFO blend refrigerants in current use are classified as A1, with low toxicity and zero flammability. Ammonia, which has been in use for many years, is classified as B2L; R-152a is an A2 refrigerant, and all hydrocarbons are classified as A3.
What is R-32 refrigerant?
R32 refrigerant is a low global warming potential (GWP) alternative to R410A commonly used in new air conditioning systems. Globally, small air conditioning systems are rapidly transitioning from R410A to R32.
What refrigerants are A3?
Hydrocarbon refrigerants such as R290 (propane), R600 (butane), R600a (isobutane) or a blend of these are rated A3.
How are refrigerants numbered?
According to an international agreement, refrigerants are represented by the letter R (as in Refrigerants) followed by a two- or three-digit number and, in some cases, one or two letters. The designation Rxyz is determined by the chemical composition of the molecule, as described below.
What is r500 refrigerant used for?
Product Information. Designed to be a higher capacity R-12 type refrigerant, R-500 found some use in air conditioning and dehumidifier equipment and in positive pressure centrifugal chillers. Since the CFC phaseout in 1995, limited quantities of R-500 are still available for service.
What pressure is r500?
It has a critical temperature of 222 degrees Fahrenheit, a critical pressure of 642 per square inch and a critical specific volume (Cu.
Is R22 still available?
R22 is no longer produced or imported into the United States, but it still exists inside some older HVAC units. If your unit uses R22 and runs out, HVAC technicians may still have access to the existing recycled or recovered R22 supply and can service your unit as normal.
What does the L mean in A2L?
2L (MILDLY Flammable) A2L: Low GWP, HFC replacements.
What do the letters mean in refrigerant?
The basic structure of the numbering system is the “chemical group” of refrigerant, followed by a dash (-) and a series of numbers and letters. For example, HFC-134a is represented by “HFC” as its chemical group and “134a,” which identifies the chemical composition of the refrigerant.
How do I find the operating pressure for a single component refrigerant?
With the blend you read the saturated temperature next to the pressure in the liquid (bubble point) column of the chart. For a single-component or azeotropic refrigerant, the operating pressure for the low side of a system can be found by cross referencing the desired coil temperature on the PT chart.
What is a Class B refrigerant?
Class B refrigerants are refrigerants for which there is evidence of toxicity at concentrations below 400 ppm by volume, based on data used to determine TLV-TWA or consistent indices. There are four classes of flammability: 1, 2L, 2 or 3.
What is the R number of a refrigerant?
List of refrigerants. Chemical refrigerants are assigned an R number which is determined systematically according to molecular structure. Common refrigerants are frequently referred to as Freon (a registered trademark of DuPont).
What is a Class 1 refrigerant?
Class 1 is for refrigerants that, when tested, show no flame propagation at 140°F (60°C) and 14.7 psia (101.3 kPa).