Error: Instability in Room.....

[bootsam]

Time step is 1
control rad fraction is zero
gain and vent levels normal
no macroflo's

still i get this error. Its doing my nut in. Any tips?

[bootsam]

I exported as gem file. Re did thermal attributes and now it runs fine???????

[Complex Potential]

That doesn't surprise me. The calculation engine powering IES can be quite sensitive and is a bit of a black box. You probably inadvertently fixed a tiny error somewhere by redoing the attributes. Sometimes you just have to throw your hands up and say "that's IES folks".