Refrigeration Piping Charging Residential AirConditioning R

15
Vibration & Noise in Piping
Two undesirable effects of vibration of refrigerant piping are: 1) physical damage to
the piping, which may result in the breaking of brazed joints and consequent loss of
charge; and 2) transmission of noise through the piping itself and through building
construction with which the piping may come into direct physical contact. Both can be
eliminated or minimized by proper piping design and installation.
Using Manufacturer’s Pressure Drop & Velocity Charts
Always size for pressure drop first, then velocity. On the top right of the pressure drop
chart in Figure 8-3, you will find tons of refrigeration or cooling capacity calibrated in
Btu per hour up to 1 ton, and in tons of cooling from 1 ton to 100 tons. You start the
sizing procedure by drawing a straight line from your system’s designated capacity
through the diagonal lines on the right side of the chart.
The diagonal lines represent:
• The “evaporator temperature”, used to size the suction line.
• The “discharge line” temperature, used to size the hot gas discharge.
• The “liquid lines” diagonal line, used to size the liquid line.
15