Pretty--But---Wrong

[Charley L. Bottger]

Originally Posted by bzimbelman

For those of us who are not HVAC gurus, what is the functional problem with this installation?

When you just tap into a trunk line without a wye fitting you have to depend on static pressure on the trunk to get air flow to the register. Those two drops in the pic have less air flow than the ones with wyes.

I was taught to never install a drop on the bottom as it would be the first place any condensate in the line would exit the system. I like my ducts basically water tight.
I was taught by old men that had never looked at a code a book and basically I did not either and now I am old

The basic that I was taught when running duct (metal) was to alway start at the plenum with the trunk line. The seam in the snap lock duct is alway turned to the top of the run with the crimp end of the pipe pointing toward the register end of the run.

I always pre-insulated my duct before I screwed the joints together. A roll of insulation is 4 feet wide. A joint of pipe is 5 feet long so when you pre-insulate it leaves 1 foot of bare metal. You just simply pull the insulation down the duct to where you get to the first wye, makes a neat install. I also pre-insulated my wye's which no one takes the time to do now days looks like slop. All of the seams in the insulation should be turned to the top of the duct and in line with the next section. I always tucked my seams and stapled every seam to where there was no pink showing. My nick name was NO PINK but when I finished it looked professional as if someone cared about their work even though not many people ever saw the work. Back in those days we did not have dumb HI's that wanted to crawl under homes for money
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[David P. Valley]

Charley,

I've got to have a picture of the upright in the attic (for my web site).

Do you have it?

[klott]

Originally Posted by cbottger

What do you see wrong with this duct install?????

Any condensation would go straight down those bottom duct's, and although I like the way the trunk line is up high,(easy to get around) they could have saved 50% of the materials, if it was installed at the bottom. But you're right, it sure is pretty.

[Charley L. Bottger]

Originally Posted by dvalley

Charley,

I've got to have a picture of the upright in the attic (for my web site).

Do you have it?

I have one David but not a good quality Pic the platform was not very big and I was trying not to stick my feet through the ceiling. Sorry

[bzimbelman]

Originally Posted by cbottger

When you just tap into a trunk line without a wye fitting you have to depend on static pressure on the trunk to get air flow to the register. Those two drops in the pic have less air flow than the ones with wyes.

I was taught to never install a drop on the bottom as it would be the first place any condensate in the line would exit the system. I like my ducts basically water tight.
I was taught by old men that had never looked at a code a book and basically I did not either and now I am old

The basic that I was taught when running duct (metal) was to alway start at the plenum with the trunk line. The seam in the snap lock duct is alway turned to the top of the run with the crimp end of the pipe pointing toward the register end of the run.

I always pre-insulated my duct before I screwed the joints together. A roll of insulation is 4 feet wide. A joint of pipe is 5 feet long so when you pre-insulate it leaves 1 foot of bare metal. You just simply pull the insulation down the duct to where you get to the first wye, makes a neat install. I also pre-insulated my wye's which no one takes the time to do now days looks like slop. All of the seams in the insulation should be turned to the top of the duct and in line with the next section. I always tucked my seams and stapled every seam to where there was no pink showing. My nick name was NO PINK but when I finished it looked professional as if someone cared about their work even though not many people ever saw the work. Back in those days we did not have dumb HI's that wanted to crawl under homes for money
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Thanks for educating this ol' HI I think I've got it, but I'm still a bit confused

So, lets say that main line was down resting on the insulation, and there is a duct directly under it (typical of many homes built in the 70s around here). Are you saying that the duct directly under the main line will have condensation issues?

What about the duct that has a proper wye to say a bedroom duct via flex line, but that flex line then turns down to the duct? Is that not a problem because it's at the end of a line, not directly under the main line?

Oh, and how do you write up this kind of issue?

[Charley L. Bottger]

Originally Posted by bzimbelman

Thanks for educating this ol' HI I think I've got it, but I'm still a bit confused

So, lets say that main line was down resting on the insulation, and there is a duct directly under it (typical of many homes built in the 70s around here). Are you saying that the duct directly under the main line will have condensation issues?

What about the duct that has a proper wye to say a bedroom duct via flex line, but that flex line then turns down to the duct? Is that not a problem because it's at the end of a line, not directly under the main line?

Oh, and how do you write up this kind of issue?

Well first off I don't write up bad designs not what we do as HI'S.

No I am not saying that just because the drop take off is on the bottom you will automatically have condensate issues but if there is a condensate issue the outlet on the bottom will be where it shows up first. Its just not good engineering practices to place the drop on the bottom. I see a lot of contractors that do place them on the bottom just not my choice. You will see a lot in commercial installs with rectangular ducts with the insulation on the inside and this duct will be in the dead space of a dropped ceiling with the take off coming out of the bottom straight to a 2X2 drop in grill this saves on material used but still not a good design.

If a duct system is properly insulated there typically should not be condensate issues within the duct but it can happen and this was alway a concern to me as an installer I would seal my joints with mastic with the take offs on the side so that if any condensate did form within the ducts it would not leak on to the dry wall ceiling or out the registers keep it contained within the ducts give it a chance to evaporate and discharge into the home as humidity rather than a rain forest. Not that we desire high humidity but that would be preferable over liquid water.
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[bzimbelman]

Originally Posted by cbottger

Well first off I don't write up bad designs not what we do as HI'S.

No I am not saying that just because the drop take off is on the bottom you will automatically have condensate issues but if there is a condensate issue the outlet on the bottom will be where it shows up first. Its just not good engineering practices to place the drop on the bottom. I see a lot of contractors that do place them on the bottom just not my choice. You will see a lot in commercial installs with rectangular ducts with the insulation on the inside and this duct will be in the dead space of a dropped ceiling with the take off coming out of the bottom straight to a 2X2 drop in grill this saves on material used but still not a good design.

If a duct system is properly insulated there typically should not be condensate issues within the duct but it can happen and this was alway a concern to me as an installer I would seal my joints with mastic with the take offs on the side so that if any condensate did form within the ducts it would not leak on to the dry wall ceiling or out the registers keep it contained within the ducts give it a chance to evaporate and discharge into the home as humidity rather than a rain forest. Not that we desire high humidity but that would be preferable over liquid water.
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Very informative, Thanks!

[Greg Veal]

Charley,

Something else I never see any more are balancing dampers. Every branch takeoff had a damper in every system we installed.
We use to install Upflow as a first choice over horizontal, and almost never downflow/counterflow units in this application. Hangers don't seem to be a problem here, but I see flexduct installed wrong on most every house I inspect, and I write up, especially on "New" construction.
Out on a H/I today and the central R/A (16" flex) to a ceiling mounted F/G had collapsed under the suction. Builder said the system had been running fine for 2 weeks. Only a matter of time, if damage hasn't already occured.

[Charley L. Bottger]

Originally Posted by gveal

Charley,

Something else I never see any more are balancing dampers. Every branch takeoff had a damper in every system we installed.
We use to install Upflow as a first choice over horizontal, and almost never downflow/counterflow units in this application. Hangers don't seem to be a problem here, but I see flexduct installed wrong on most every house I inspect, and I write up, especially on "New" construction.
Out on a H/I today and the central R/A (16" flex) to a ceiling mounted F/G had collapsed under the suction. Builder said the system had been running fine for 2 weeks. Only a matter of time, if damage hasn't already occured.

Greg I hardly see a quality duct install any more these kids now days just slap it together and grab the money and run.

Where you been missed your posting hope health is good.

[Greg Veal]

Thanks Charley.
Things are going pretty well, a few blips along the way, but pretty much OK.

I've been slower than I want to be, but it has worked out, because we have been busy with our parents.
Things have really slowed in our area. Talking to buddies at our monthly chapter meetings, everyone is sucking wind, have been for the past couple of months. It doesn't look good for the near future.
Hope you're busy.

[Charley L. Bottger]

Originally Posted by gveal

Thanks Charley.
Things are going pretty well, a few blips along the way, but pretty much OK.

I've been slower than I want to be, but it has worked out, because we have been busy with our parents.
Things have really slowed in our area. Talking to buddies at our monthly chapter meetings, everyone is sucking wind, have been for the past couple of months. It doesn't look good for the near future.
Hope you're busy.

Glad to hear you are alright

Business here has slowed a little but not bad I bought the B-Cam and have a lot of intrest in it. Also hooked up with a water Restoration company I do the mold testing for them as Ok. changed their Laws you can not test for mold and do the restoration too as it should be. With all of the rain we have had this year mold is booming.

[Ted Allen]

Nice post Charley!