Can you explain and show your calculation going from pa to cfm?
Had a fan tech flex 100 HRV installed
Testing with manometer to balance gives exhaust of 92 pa and intake of 99 pa regular speed and 66 pa exhaust and 69 pa intake on reduced speed
With 4” ducts my calculations seem to convert this to cfm of
Regular ex 213 cfm in 221 cfm
Reduced ex 180 cfm in 185 cfm
despite the machine being rated at 100pa=122 cfm by the brochure
can anyone explain or assist with this please
Tks
Can you explain and show your calculation going from pa to cfm?
You lost some replies. Your CFM calculation does not give the actual airflow. Your calc gives the system curve but assumes the statics are developed by CFM. The fan can't do that so your CFM is a lot lower than you calculated.
No man can be both ignorant and free.
Thomas Jefferson
Looks like the op is creating multiple threads on the same topic.
https://hvac-talk.com/vbb/showthread...-seem-too-high
and a couple of others