|MarketManager » Loads and Sizing|
1. The Zone | Sply Air form:
First, let me explain how the Zone | Sply Air form works.
- MarketManager already knows the zone loads for the zone (as they are recalculated each time you input something).
- MarketManager also knows the zone design temperatures for heating and cooling (which are located at the bottom of the Zone data form).
- In the Zone | Sply Air form, there are inputs for supply air temperature for heating and cooling. The defaults for these are 110F and 55F. The Zone | Sply Air form uses the equation listed below to determine cfm requirements for heating and cooling (they are not the same):
- When you autosize zone air, MarketManager will take the maximum of:
Zone Loads = 1.08 X cfm X T
where T = (Tdesign - Tsupply) for cooling and (Tsupply - Tdesign) for heating
- the cooling supply air requirement (cfm),
- the heating supply air requirement (cfm), and
- the ventilation requirement (cfm) (which come from the Use Defaults form).
The greatest of these three will be the Zonal Supply Air requirement.
2. The System Form:
The System form will sum all the Zonal Supply Air requirement for all zones attached to the system. You can see this near the bottom of the System | Detail form. (It says "sum of zone cfm = " and some number.)
When you autosize fans, the fans will be sized to match the total zonal cfm requirement as shown in the System | Detail form (mentioned above).
Otherwise feel free to contact our Tech Support staff at (805) 329-6565, or via email at firstname.lastname@example.org.