Hi,
Typically I would calculate my Heat gains in summer time in order to get a peak coincidental load. However, I have been asked to produce a number of Heat gain calculations - one for each week of the year. I have noticed that when I run a heat gain calculation and set the outside conditions design day/month to January 7th, between the hours of 9pm to 7am, instead of a heat gain figure I am presented an asterix (*). Above the table it mentions that the asterix (*) = Sensible fresh air load excluded. Why is this figure being excluded from the Heat gain calculation?
Kind regards,
Tony
Hi Tony, my first thoughts would be perhaps this may be a loss rather than a gain, considering the time of year and day. For example the losses through infiltration may be exceeding your heat gains. If you wish to include this in your heat gain analysis please select the Include losses with gains option on the CIBSE Gains Design data menu.
Shane Regan | Principle Building Performance Support EngineerHevacomp to OpenBuildings - A complete guide for every user | Bentley Communities
Hi Shane,
Thanks for getting back to me. However, the 'include losses with gains' option was already selected. I have noticed that even when setting the design day/month to July 7th I am still getting the asterix between the hours of 9pm to 7am. This isn't something I have had an issue with before, I thought perhaps I have set some kind of profile by mistake to only provide me Heat gains values between 8am-8pm. So I have done a global change to the '24 hour operation' profile, however this still does not seem to have resolved the issue. Any further recommendations would be appreciated.
Hi Tony,
No problem, I'd like to have a look at your project if you could please upload the project folder to this link.
Thanks,
Shane
Thanks, project has been uploaded as a zip file.
Thanks Tony, the limited results were just due to your settings for Cooling Plant operation time, in Building Data, as below. If you set this to 1-24 all hours will be reported.
Answer Verified By: Tony Carter
Thanks
No problem Tony.