Well, we had to get a new HVAC system.  What is HVAC you ask?  It stands for Heating, Ventilating, and Air Conditioning.  In our townhouse, we almost never thought twice about our HVAC system, or what was going on with it.  I’m sure you haven’t either unless it stops working!  Well, now we have a (kind of) understanding of the whole thing.

Time for my very first disclaimer:  No, we are not HVAC professionals.  Read up on installing duct work in your own house on some other, more official web site, before attempting this yourself so you know the proper terminology (vs. my use of “that thingy.”) I also personally apologize for the “man project” nature of this post.  Hey, sometimes you gotta do this stuff!

Our house is on a “dual zone” system.  That means, we have two thermostats that are linked to completely separate systems.  One system has the thermostat on the main floor and heats and cools the main floor and basement.  That system has a gas furnace, which works, and a questionable air conditioner that we are worrying about in the spring.  The upstairs system is based on a heat pump, which uses only electricity in an outdoor unit that resembles an air conditioner, and an indoor “air handler” that distributes the heated or cool air throughout the house.  That’s what we got replaced – the old one had a host of problems – like flooding the ceiling in that one room.  We were basically told by several people that it wasn’t worth fixing because it was old and crappy.

So, we have our new, lovely energy efficient model (for which we will get some major moolah rebates come tax season, and from our electric company.. which only slightly softens the blow of how much this crap costs).   However, the technician that installed the unit said that the flexible ductwork that is used for the air returns left something to be desired.  In fact, one of them was imploded (collapsed) and he couldn’t get a new efficiency reading on it to get us our happy rebates.   This is the air handler up in the attic with the old, ghetto return duct:

Oak, being the frugal/clever fellow that he is, asked that we replace these returns ourselves.  I don’t remember if we got a quote on having the technician do this, but I’m sure it would have been at least another $300 for labor costs.  And it totally was NOT difficult!  It didn’t even really involve any “man tools” – I know, bummer! After Oak found a place that would sell HVAC equipment to regular folks (as many will only sell to the pros), he bought some lengths of flexible ductwork, mastic (which is a special adhesive), special duct tape (not the gray kind we’re used to!) and uber long zip ties.  That’s about all you need!

We did the short duct first.  This duct goes from the right side of the air handler (the right vent in the picture above) to the return vent in the hallway.  I’m only going to show the pictures from attaching one end because it’s basically the same thing at either end of the duct – one end goes to the air handler, and the other to the vent.

First, you must hug your duct.  Oh, it’s lovely and shiny!

Now look at the awesome hole where your vent comes out.  Wow.  You can see downstairs!  Next, apply the mastic to the metal circular part of the vent with a cheap, or old painbrush.  Basically whatever you use is effectively going to be ruined.  This stuff is super sticky, but spreads on like a thick paint.  Go all the way around the vent:

Now, it’s time to attach the vent.  Start by sliding off the shiny part and attaching it to the mastic.  Then, affix a zip tie over the whole thing to really hold it in place.

Slide the shiny part back into place and you’re done!

Now repeat this on the other end of your duct.  Pretty simple eh?  The other duct (the one that goes to the bonus room) was a little more complicated because it was longer and involved climbing into another, less accessible part of the attic.  Here’s Oak squeezing his way through :

And the shiny new, un-imploded vent in place. Our technician suggested running the duct under our hard ducts, which seems to work better than it going over the top like the old set-up did.  Ding!

If you have any leftovers, you can fashion yourself an ultra-stylish robot costume!  Just kidding.  We actually had an entire length left over that we are going to exchange for some of the smaller ducts that carry the heat into the rooms.  The ones we have work, but we can replace them for a higher “R-value” (ie better temperature retention).  So, I may be returning with more HVAC fun in the future!   Congrats if you made it to the end of this post without getting bored..

Posted by Carrie on Monday, January 11, 2010
Categories: blog, home improvement · 3 Comments »