Dear e-quest user,
I am sure this is a common case and many of you have modeled this before.
I have several spaces which are heated only with unit heaters (electric heat). If there is no cooling, per ASHRAE Appendix G , the cooling in proposed case should be the same as cooling in my baseline. How would you model this? What type of system and what type of cooling should I use in my propose and baseline? This is a residential building, 170,000 s.f. with non-residential area of about 45,000 s.f. Spaces I am talking about are stairs and mechanical rooms.
Thank you for sharing your expirince and advice.
Ana
Ana,
Since this is a residential building, your baseline system is PTAC (or
PTHP if you have electric heat in the proposed). So put PTACs in your
proposed model stairwells and mechanical rooms, with electric heat, and
using the fan power and cfm of your unit heaters. Create
stairwell/mechanical room cooling and heating thermostat schedules, with
the cooling thermostat high and the heating thermostat lower than your
living spaces. Then use the same thermostat schedules for proposed and
baseline.
Regards,
William Bishop, EIT, LEED(r) AP