Mini Split vs. New Ducting to Fix Low Flow HVAC
Purchased a 25 year old home for ourselves last year and turns out the master bed has virtually zero air flow at the registers (ceiling). Wonky HVAC design feeds the master with LONG (20’+) flex duct sections in the attic crawlspace (3 floors incl. finished basement). Furnace is 5 years old and a high efficiency unit. Same for A/C.
I’m thinking that we want to replace a lot of that flex duct with rigid so only the last 5+ feet are flex and then get dampers on all the registers and flip them seasonally. (Colorado). Flipping register dampers twice a year made a huge difference in our prior, very similar, house.
Had a reputable HVAC specialist out and he didn’t want to even consider improving the ducting: He’s convinced we need a mini split. He was skeptical we could get much improvement at all with the duct enhance and new registers. Cynical side is wondering if they just don’t want the hassle of working sheetmetal in the 50″ tall crawlspace.
What do you all think? I know mini splits are all the rage but I’m inclined to fix the forced air system. Still, I don’t want to waste my dollars in a potentially futile direction.
Thanks,
JD
Replies
If the rest of the hvac system has the capacity, it seems to me a better path to fix the air ducts. (make sure they are smooth, sealed, and well-insulated.) Run a return while you are at it. same care for sealing and insulating.
You can also add an extra fan to help move the air if needed.
I was wondering about a booster fan- heard of them but not employed one before. The wiring for it could be costly (patching drywall) unless there is a reliable wireless solution these days. Thanks.
The National Comfort Institute (funny name) provided certified pros on balancing HVAC- only 3 within 125 miles of me and there are about 3.5 million people in that area- pretty rare. I will get one of them in next.