150 likes | 631 Vues
Infiltration and Ventilation. Heat Loss Due to Infiltration. Infiltration Btu H = (.018) x (ACH) x V x (T i – T o ) ACH = air exchanges per hour V = volume T i = inside temperature T o = outside temperature. Heat Loss Due to Infiltration. OR.
E N D
Heat Loss Due to Infiltration Infiltration Btu H = (.018) x (ACH) x V x (Ti – To) ACH = air exchanges per hour V = volume Ti = inside temperature To = outside temperature
Heat Loss Due to Infiltration Infiltration Using equation 2-11 page 34 and applied to Problem 2-1 page 41 Btu H = 1.1 x CFM x (Ti – To) CFM = (ACH x volume) / 60 min per hour
Heat Loss Due to Infiltration Infiltration Please Note: For tight construction use 0.5 for ACH. For medium construction use .85 for ACH. For loose construction use 1.3 for ACH. For really bad construction use 2.0 for ACH For the summer months (cooling) use 70% of the winter values.
Heat Gains Due to Infiltration • Latent Load BtuH = 4500 x (air exchanges x (volume) /60) x (W Final – W Initial) (W Final – W Initial) = Difference Ratio Pounds of Moisture per dry air
Heat Loss Due to Ventilation Ventilation Btu H = 1.1 x [(Ra x square feet of building ) + (number of people in the building x Rp )] x (Ti – To)
Heat Loss Due to Ventilation Ventilation Ra = Area Outdoor Air Rate Rp = People Outdoor Air Rate Example: Pharmacy Ra = .18 Rp = 5
Heat Loss Due to Ventilation Ventilation Btu H = 1.1 x [ (.18 x 3,632) + (30 x 5)] x 76o = 67,214
Infiltration and Ventilation • I hope this clears the problem up! • Let us move on.