HRV Main duct size

brad_14

Howdy,

I'm in the process of wrapping up my air handling system.

I have used an older lifebreath 300DCS HRV running into a new Lifebreath 3000TFP Hepa unit. The two are connected together with 7" flexible duct with a 7"x7"x4" balancing T the 4" is open to the room. The HRV is Supplied and vented with 6" insulated duct.

Attached I have a sketch of the system with vents and supplies spaced roughly to scale and location each square is 2'. U signifies up and D signifies down its a rancher with a daylight basement so up ones would be + 8' roughly. The boiler room is centrally located so there will be 1 supply and vent line to the right and one vent and supply line to the left. My question is will a 6" round each way work or is 7" more fitting.

The house is 1800sq' rancher daylight basement with joist trak on main and in slab in basement fired by a TT 110.

Any and all help or advice on my ducts and or HRV ductwork in general is apreciated.

Thanks
Brad