Two stage variable speed furnace worth it? - No bike content

[blackcat]

Fact is , with a bit of research and measuring cubic footage it isn't all that difficult to design a duct system . One of the last systems I installed was all done in PVC . Yes , a bit more expensive , and it required precise measurements , but will never leak or rot out . Even the plenum was PVC . It does require plastic capable of dealing with the heat .

 Dusty

I didn't know it could be done with PVC. The plenum pipe must be fairly large.

[oldbike54]

I didn't know it could be done with PVC. The plenum pipe must be fairly large.

 The plenum was actually a box approximately 32 " high and sized to fit the top of the A coil . Made from some high temp plastic , double walled with insulation pre-installed . Used a very large adjustable hole saw to make the starter holes . Don't remember all of the details re sizing , seems the largest pipe was 10" . Kind of pricey , but it was what the customer wanted . All modern down flow systems , where the duct work is under the slab are done in PVC . The only real difference was the need to insulate the pipe in my example . Just used regular fiberglass wrap , stapled and zip tied on .

 Dusty