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I'm wondering about a term in ventilation called the air-exchange number. It is used to calculate a buildings heat loss through infiltration. It's measured in 1/h (h=hour), and is calculated as L/V where L is m3/h and V is the room volum in m3. I'm wondering about this L, is this the amount of air brought into the room by the vent system? I just can't see what else it could be...

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I'm supposed to evaluate the accuracy of a specific HVAC program. I thought I would first calculate (by hand) a rooms different u-values. Then I will heat up the room to a certain temp, let it cool for a certain time period, and then measure that room and adjacent rooms' temps. This will give me a loss of Watts "before and after". Now I'm not quite sure what to do with these values, not even sure if I'm on the right track, so if anyone has any ideas as to what I can do I'd really appreciate it :-)

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# Air-exchange number

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