
However, the use of the RRL allows the designer to look at the range of supply air conditions that could be used if there was flexibility in the design supply air temperature. Looking at the chart (Figure 1) these two methods provide the same supply air point – the simple calculation method is probably the most reliable. As an alternative to using the RRL to determine the supply air point, the room latent load may be used to calculate the supply air moisture content from ΦL = hfg (gR – gS) and so reading the value of gR from the chart as 8.8g The intersection of this line with the specified value of θSC (ie 16✬) provides the summer supply air point SC. The summer room sensible/total heat ratio will be 5.0/(5.0+1.2) = 0.81 and since this is a coincident sensible cooling and latent cooling load, the gradient of the room ratio line (RRL) is taken from the bottom quadrant of the protractor on the psychrometric chart and is drawn through summer room point RS.
#ASHRAE PSYCHROMETRIC CHART EXPLAINED PDF#
Email a list of all the points and their properties for a completed chart, along with a PDF of the chart itself.Also, create custom labels anywhere on the chart. Create psychrometric processes by plotting points then connecting them with process lines.In addition, you can double-tap a point to display the point properties and then edit them. As you move your finger around the graph, the psychrometric properties at the top of the screen dynamically update. Using your finger, plot as many points as you want on the screen.Customize the graph in many different ways, including specifying the psychrometric chart line colors, chart background color, hide/display status of chart lines, point colors, process line colors, units of graph values, and the min/max limits of the chart.Display a fully customizable psychrometric chart in both landscape and portrait modes.The ASHRAE Psych Chart app includes the following features and functionality:


The new ASHRAE Psychrometric Chart app is the first truly interactive graphical psychrometric chart for your iOS device, and it includes both I-P and SI units.Įasily plot HVAC and other psychrometric processes while out in the field, save the graphs, and then email the graph and results to yourself or clients.
