Incoming Air Pipe Reduction

[Crumpetman]

Hi

Bit of Newbie so might be a stupid question. The MVHR unit I have purchase has 180mm spigots would it be ok to reduce these to 150mm as this would allow me more options for air distribution box's?

Many Thanks

Andy

[JohnMo]

You would need to calculate the pressure drops over the system based on your flow requirements.  So no easy yes or no I am afraid.  You should be able to datasheet from the manufacturers website for ducts etc.  You want as low a pressure drop as practical to fan speed down and noise.