Question-and-Answer Resource for the Building Energy Modeling Community
 | 1 | initial version |
50°C (122 F) is not unusual (as an initial default value) for zone heating supply air (especially for older designs), although 30°C to 35°C (~90F) is preferable. It may be higher than 50°C in some cases, yet I think 50°C is a code-set maximum temperature for insulated ductwork (foamed plastic insulation). ASHRAE 90.1 requires a maximum supply of 11°C above setpoint (e.g. 32°C if setpoint is 21°C). In any case, a decrease in heating supply air temperature involves a proportionate increase in airflow rate - a balance that would depend namely on peak heating loads IMO.
