Blast gates for hvac pipe

[Bob Cooper]

I used snap lock 26 gauge pipe and fittings. I found the prices at the hvac houses much cheaper than Home Depot. I had to order the wyes though and they had a different name than what I expected. Even ordering them they were much cheaper than pvc. Since the made then I told them not to crimp them since I knew the airflow would be reversed. Then I crimped them myself. The tool is cheap and it's easy to do. Also I taped every joint using AL tape

[Carl Kona]

Dan,

If you have the HF DC and are using metal ducting you will probably find the sweet spot at 5" not 6". Many of the guys on the Thein forum built units around 1.5HP DCs and calculated that 6" was too big for most people. I am not sure what size impeller HF uses on the 1.5 HP DC but on the 2HP they use a very small (for the size of the motor) impeller of only 10" versus 11-12 on most 1.5-2HP DCs. With the smaller impeller, less CFM, less velocity. The lower velocity will not be enough to keep stuff moving in your duct. So in this case bigger is not better. If you are interested in KenCraft Wyes I have 4 extra brand new 5" Whyes (PM me for details).

Hope this helps,

Carl