CYPETHERM. "Thermal loads" tab – Calculation options

Associated programs

CYPETHERM

Configuring the calculation options in the "Thermal loads" tab

The "Calculation options" can be configured in the "Project" section of the top toolbar on the "Thermal loads" tab.

The available options are as follows:

Heating loads calculation

Analysis method
- ASHRAE
  When this option is selected, the program uses ASHRAE’s Radiant Time Series Method (RTSM) to calculate heating loads.
- Standard EN 12831
  When this option is selected, heating loads are calculated in accordance with standard EN 12831. In this case, the following parameters must be defined:
  - _n50 coefficient
    - Defined
    - Calculated
      - Air-tightness rating of the building envelope
        
        High (high-quality insulation for doors and windows)
        
        Medium (double-glazed windows, standard insulation)
        
        Low (single-glazed windows, no insulation)
        
        Air permeability of the building envelope at 4 Pa
      - Number of floors in the building
  - Type of building (Detached house / Residential / Offices / Hotel / Restaurant / Educational / Healthcare / Other uses)
  - Protection class (No protection / Moderate protection / High protection)
  - Correction factor due to outdoor dry-bulb temperature oscillation
  - Reheating factor (optional)
    The reheating factor is a correction factor, defined in EN 12831, which depends on the characteristics of the building and the installation. The annexes to this standard propose different values for this parameter depending on the building type, its mass, and the assumed reheating time and rate of internal temperature drop during shutdown. By clicking on the button on the right, you can define these parameters and import the associated value for the reheating factor:
    - Reheating time (hours)
    - Interior temperature drop
    - Building mass (High / Medium / Low)