Welcome to the TRNSYS Users Forum.
The forum is a place where people can interact and have discussions about different topics involving the use of the TRNSYS software package. Here you can post topics for discussion or questions on using TRNSYS and get advice from other users or TRNSYS experts. This forum is not intended for detailed technical support. Users should contact their distributor’s hotline for such assistance.
Some tips for success on using the forum:
- Follow the Forum Rules posted in Forum Administration.
- There are categories for different types of topics and questions. Post your topic or question into the proper category.
- Before posting a topic or question search the existing topics (and the TRNSYS Users listserv archive or Post archive) to see if a similar topic or question has already been answered.
- Use a descriptive topic name. Don’t use attention getting subjects, they don’t get attention and only annoy people.
- State the version of TRNSYS and which add-ons your are using.
- Include enough specific details for your topic of question to be answered. Just posting “Why am I getting an error?” without describing the specific error and what you are trying to do when you get the error will not receive a response that fixes your issue.
- Remember when people help you, they are doing you a favor. Be patient, help people out by posting good descriptions of what you need help with, and be polite even if a response does not solve your issue.
- Moderators may edit your post for clarity or move your topic to a more appropriate category.
Last seen: Apr 29, 2026
@ken, The short answer is that I would recommend making sure that the two surfaces have the same slope and azimuth. The longer answer is that ...
@jolind Type362 is a radiator model that was written by Transsolar. I have not used it. There is more information about it available at www.trnsys.d...
@humbertosantos Humberto, I am sure that I am missing some nuances of what you are trying to do but if you use an equation to add the heat pump's powe...
Luis, Type48 can be a bit tricky and on the many times that it was doing something confusing and I took the time to walk through the code a line a...
@takaya14 I have seen a few approaches to this issue. When the screen is open and there is a large horizontal opening then in the real world situa...
@tagreedwael Typically you would set up the active layer in TRNBuild so that it has an inlet temperature and mass flow rate defined as inputs to Typ...
@antonio Type560 is a bit more of the theoretical model but the principles are more or less the same. If you have one panel and want to add a second...
@xenia-kirschstein thanks for posting this announcement and for contributing to the community! ~david
@sw17032 sorry for the delay in getting back to you. If there is a difference between the inlet and outlet temperature, even if it is very small the...
@tskiado TRNOpt is an interface that facilitates setting up optimizations run by GenOpt (a generic optimization tool written by Lawrence Berkeley Na...
@juliatig This forum is intended to be a place where users can help users. You are welcome to post questions here. If you need support beyond what t...
@antonio sorry for not replying sooner on this. My guess is that either TRNSYS was installed in the .\Program Files\ directory (it should not be) o...
@amir_i The idea of Type780 is that you pass a moisture gain rate to the building model, which in turn deals with the latent energy impacts of addin...