I'm having difficulty simulating a naturally ventilated space using the Monodraught windcatcher components. The model will run if I don't add any heat gains to the space, however if I add any heat gains the analysis fails due to:

"Instability in room. Possible remedies: reduce time step; set radiant fraction to 0; check gain and ventilation levels; reduce MacroFlo opening areas."

Does anyone have any ideas?

I'm having difficulty simulating a naturally ventilated space using the Monodraught windcatcher components. The model will run if I don't add any heat gains to the space, however if I add any heat gains the analysis fails due to:

"Instability in room. Possible remedies: reduce time step; set radiant fraction to 0; check gain and ventilation levels; reduce MacroFlo opening areas."

Does anyone have any ideas?