Hi all,

I'm working on an energy model for a project that is very interested in
incorporating a mixed mode ventilation scheme. The mixed mode would
operate in an on/off red light green light method where the mechanical
cooling would shut down during hours when the outdoor air temperature
could meet the space cooling loads and the mechanical system would run its
relief fan in order to pull air into the space. It would be up to the
occupants to open the operable windows.

I've been through the basic options for natural ventilation in eQUEST and
it doesn't look like what's available in eQUEST is going to work for the
PIU system I have in the building right now. I'm thinking it will have to
involve some sort of schedule modification to turn off the perimeter VAV
box fans during hours when the loads could be met by the natural
ventilation. I could make the schedule based on BIN calc information for
Seattle. This would involve a lot of fine tuning though and it would be
questionable whether I could still keep the unmet load hours under 300.
To simulate the operable windows modifications could be made to the
infiltration values at the perimeter spaces.

If anyone has had any success with mixed mode ventilation or has any ideas
towards this it would be much appreciated.

Robby Oylear