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Old 07-04-10, 12:11 PM   #74
AC_Hacker
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Default The Coward's Way Out...

Quote:
Originally Posted by mrd View Post
AC_Hacker, I haven't seen you mention static pressure. You'll need to determine the static pressure your fan(s) will be presented, then cross reference that value to the fan specs to determine if the fan will meet your airflow needs...
mrd,

Good thinking.

A friend loaned me a couple of fans (each different) to use for testing. He also loaned me an air velocity measuring transducer & meter. I'm planning to take the coward's way out and make a mock-up out of cardboard and duct tape and test the core at various thicknesses, so as to get some idea what the loss curves would look like.

I also have some samples of 3 inch pipe, and I thought if I measured the pressure drop over three or more lengths, I could get close to a velocity-loss-per-foot factor.

I'm thinking this will give me enough information to size my fans (and core) correctly.

Xringer's idea of making a small window-sized unit is also interesting to me. The up side is that the ducting issue pretty much goes away. The down side is that the HRV has to be optimized to a smaller envelope, and there are sealing issues, which aren't insurmountable, and also one side of the ERV would be exposed to outside air temp.

Pictures & data to come soon...

-AC_Hacker
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