A/C duct repair - Help!

[gplantam]

Can anyone suggest a good website for info on DIY A/C duct repair? I've searched for a good while and didn't find much detail. Is it something non-professionals are advised to stay away from?

From what I've been able to find out, duct tape doesn't work well for

A/C ducts (ironically) but mastic should be used instead. What kind of mastic? I know where the holes are. How much should I use?

Apparently, there are 2 types of ducts: the "box" kind and the kind that's like a coil in a bag. What is the proper name for the coil kind? A section of the coil kind appears crushed in my attic. Does that happen normally over the years? Can I repair that section or must I replace it?

I would appreciate some pointers from a pro. I can't really afford to hire someone right now.

Thanks,

Greg

[JoeSpareBedroom]

Maybe you could tell us what happened to your ducts that they need to be repaired. Are we talking about a 2" hole, or what? Are these rectangular ducts, or round? Do you know how to use tin snips and a rivet gun?

[Zephyr]

It is probably best to replace the damaged section.

You should use UL181 approved duct tape [not rubber back duct tape.] You should also use sheet metal collars to join the repaired duct to the new section of duct, and it is advisable to use mechanical restraint [zip ties.] The 'coiled duct in a box / bag' is flexible duct. You can use a sharp large knife to cut the duct, and a diagonal cutter to cut the spring [do not use aviation snips to cut the spring, it will ruin them.] Good luck.

[valvejob]

Lowes has some of those round insulated ducts in 25 and 50 foot lengths. They are of a much higher R value than your old ones, which means you get more cool air in the summer and warm air in the winter and it saves on your heating bill.

It is a vey easy job to replace the old with the better quality new ones.

[Al Bundy]

valvejob wrote in news: [e-mail]:

Last time I used some 8" it had, I think, R6 stamped on it.

[Al Bundy]

"Zephyr" wrote in news:3ZadnYgnlrbyyjjbnZ2dnUVZ [e-mail]:

I've used, and have seen HVAC guys use, Polyken tapes. This one meets the spec you mentioned.

[<nni/gilmer]

Yep!

And the stuff comes is wider widths which I have seen on new installations in church buildings.

GREAT STUFF. It can take higher temperatures can can be used with gas dryer vents. Holds as well as screws but doesn&#39;t "snag" or catch lint.

[gplantam]

Thanks, everyone, for your suggestions. :-)

[gplantam]

14 max positive pressure=6" water max negative pressure=1" water max flame spread 25 max smoke developed 60 max velocity= 4000 fpm R 5.6 Perm 0.1 Permaflex M-KE

[Moe Jones]

And the ZIP file has what virus?

[udarrell]

Never install a smaller Return air duct! The 14" flex duct could even be too small!

udarrell

[Telstra]

[Telstra]

udarrell