What is pH diagram in refrigeration?
A p-h diagram is a figure with a vertical axis of absolute pressure and a horizontal axis of specific enthalpy. It is an important diagram used frequently for a performance calculation of a refrigerating machine. A p-h diagram is made respectively for a specified refrigerant.
How do you use a pH diagram?
On the P-H diagram, pressure is indicated on the y-axis and enthalpy is indicated on the x-axis. Typically enthalpy is in units of Btu/lb and pressure is in units of pounds per square inch (psi). The upside down U figure shown on the diagram designates the points at which the refrigerant changes phase.
How do you read a pH table?
The range goes from 0 – 14, with 7 being neutral. pHs of less than 7 indicate acidity, whereas a pH of greater than 7 indicates a base. pH is really a measure of the relative amount of free hydrogen and hydroxyl ions in the water.
What is HVAC subcooling?
Subcooling occurs when you cool a vapor below the temperature at which it turns into a liquid. Let’s use the same refrigerant with a high pressure boiling point of 120 degrees for the following example: The refrigerant is a 140 degree vapor heading into the condenser.
Which chart is most useful in refrigeration?
Pressure-enthalpy chart is useful in refrigeration.
Is HS diagram and TS diagram same?
Mollier’s H-S diagram (Enthalpy v Entropy) was a logical extension of the T-S diagram (Temperature v Entropy) first proposed by Gibbs, retaining the advantages of T-S diagrams but introducing several new advantages. A typical H-S Mollier diagram for a thermodynamic fluid such as steam is shown in Figure 1.
What is proper subcooling for 410A?
Most heating and cooling systems should operate at a superheat of 10F at the evaporator and between 20F to 25F at the compressor. if your HVAC system has a thermostatic expansion valve (TXV), the subcooling should be between 10F and 18F.