Question-and-Answer Resource for the Building Energy Modeling Community
 | 1 | initial version |
That model calculates panel stagnation temperatures when "off" and no fluid is going through the device. A cold night and a colder night sky can freeze the water. A warm day in full sun can get really hot and boil (blow up). This can be useful for controlling when to force flow to come on for thermal protection (with an availability manager). If you don't care about special operations for freeze or overheating protection, then it should be okay to just ignore the warnings.
If you have glycol instead of water, the other problem is that the data range for fluid properties is not really broad enough for the solar panel application (having been originally done for ground heat exchangers which don't see as extreme temperatures).
