Gotta travel 2000 mi to do a hvac job this month or next, and thinking of using flex duct as don’t have to drag many tools along then. Actually never used it before, looks grade school simple, esp if one already has good understanding of pressure dorps, bends, kinks, etc. Probably use mostly 7″ and one run of 18 inch.
Any bad experiences to share??
Replies
bad experiences? yup.
Truck stops have some weird people at 3 am
what ever hi-way you take there will be construction
get gas before ya get below a quarter tank..
oh..you meant about the ducts...my bad.
Spheramid Enterprises Architectural Woodworks
Repairs, Remodeling, Restorations.
Don't drag it over anything sharp....
Repair all tears as you find them...
Two bodies to prestretch and unwind it..
Use wire cutters rated for steel....
The longer the tail pieces the more gooder...
Use black ties instead of the white...
Use the cable tie tensioning / cutter tool... You won't regret it...
Ferget regular duct tape.. Use the mfgr recomended stuff..
The rest is cake and pie...
Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming
WOW!!! What a Ride!
A lot of folks around here use a lot of this stuff.
At least one top end HVAC contractor refuses to use it. He said it is inferior to almost all other options. The insulation value is low. It has high internal friction that makes you use a much larger, less, efficient blower. Once in place anyone moving through the crawl space or attic is likely to damage this stuff. In the long run these flex ducts can deteriorate just because of the environment they are placed.
Their main up side it that it is cheap, quick, an important consideration working in a Florida attic in August, easy, and low skill, low wage, to run duct with this stuff for a house.
His preference is for sheet steel ducts with insulation and a vapor barrier applied to the outside. He claims it is durable, easy to clean should this become desirable, efficient in that when sized correctly it has less internal friction and better insulation. It is also a whole lot more time consuming to install and requires trained workers. The tools and materials are more expensive. He gets top dollar for these installations.
Some reputable AC contractors use fiberglass duct board for main runs and flex ducts for the last bit running to the registers. I guess this is better than an all flex job but not nearly as good as the sheet metal ones.
I don't know. I'm an electrician. I will say sometimes flex is nice as it can be easily disconnected to AC the attic. It also can be pushed out of the way allowing access to the electrical work. Unless it is old and brittle flex or in one of the huge sizes it is easy to climb over. On the other side I see a lot of loose connections and deteriorated, leaking or condensate saturated flex.
Fiberglass duct board is firmer, I can put my tools on it, but it can be a pain to cross in a tight attic or in larger sizes. It won't bear my weight. This can greatly increase the amount of crawling needed to do a job. In an attic at 140F this is a major pain. Transitions between ductboard and flex seem particularly vulnerable to damage and deterioration.
Sheet metal ducts seem more durable. They can be a pain in that they won't move out of the way. If the AC man missed a junction box and laid his duct across it it can be a major PITA to work on. If I'm lucky there is enough slack in the cables to pry the box free and slide it out.
The metal ducts, at least when braced, can often support my weight long enough for me to get across. The insulation is crushed but snaps back. I take care not to twist and tear the vapor barrier. A really good duct man makes provision, extra bracing or a board over top of the duct, to facilitate movement. Making a blind jump over a duct and hoping to hit a ceiling joist on the other side is entertaining but risky.
Why on earth would you travel 2,000 miles to do an HVAC job? is this S.O.P. for HVAC guys in your area?
If the money is right...
I'm guessing it is for his mom.
Jon Blakemore