Midcvfrun 8 to 6 Inch Duct Reducer Increaser Cone, HVAC Ducting Adapter 8” to 6” PVC Pipe Connector for Grow Tent Basement Bathroom Kitchen Ventilation System

This good quality air duct reducer is just what I needed to connect a 6" air duct tubing to an 8" opening on a large carbon filter in my grow tent. I needed a larger filter inside the tent to process more air flow but did not want to have to upgrade the blower fan which has a 6" opening. I have a short section of 6" air duct tubing that connects the 6" blower and 8" filter together now by using this reducer collar. It has a thick plastic collar but should not be used for any plumbing since it is not as heavy duty for water lines, but will work great for air ducts. I did not know they made these so I was very glad when I found this product available to order. Depending on your needs for this it may or may not fit so just be aware that the exact measurements of this reducer are as follows: on the 6" end the inner diameter is 5 5/8" and the outer is 5 7/8" - on the 8" end the inner diameter is 7 7/8" and the outer is 8 1/8".

I needed to size down an 8" flexible HVAC duct to a 6" grille. The Midcvfrun 8 to 6 Inch Duct Reducer Increaser Connector is pretty much the same price as its galvanized tin equivalent from the big box store, so I gave it a shot for my HVAC project. It worked great. Now, having said that, I must admit that one end of my connection is a flexible round duct, so that wiggled on with zero issue. The other end of the connection is an equal diameter plastic grill, so neither side of that connection will slip inside the other. I butted them together and wrapped it with a good duct tape. I point this out because the advantage of this nice sturdy plastic fitting (stout, and no seams for leaking) is also its downfall. There is no ability to crimp or adjust it so that another fitting will slide into or over it. If the OD of this fitting is not a little larger, or smaller, than the mating pipe, you will be faced with making all adjustments in areas other than the Midcvfrun fitting itself. It worked great for my application, but I did not have to work it into a continuous galvanized HVAC run. My connections were low tech and flexible, so it worked fine.

Plastic seems to be decent enough, though the edges are somewhat jagged (nothing a deburring tool won't fix).The real problem is the mismatch between the product description and sizing. Pictures clearly show the 8" duct OVER this reducer, and the reducer 6" side OVER the 6" fan. Well, neither of them fits that way (at least with AC Infinity equipment), which makes it useless for the intended purpose.It may work if used the opposite way - it does fit over an 8" fan (however, with no obvious way to secure it - it doesn't look like a clamp will hold it in place), and it may fit into a 6" duct (can't verify, don't have one).

This is a thin wall fitting, looks to be schedule 20 though it is not marked in any way. It is not for drainage but for air ducting only. My intent is to use this to adapt a hose to my walk behind leaf blower, though I'm not sure the hose will fit and I will have to get inventive. The product is as the listing says - just check the sizes (after converting to inches) to be sure it will fit what you are doing with it.

Great study collar. Does a great job changing over my 8 in filter to 6 in fan.