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Duct board repair/starter collar holder help

chicken123 | Posted in Building Code Questions on

A contractor who installed my heater wrong/ I had to replace it after 12 years.
is now fixing my duct system to make me happy, (per them)
the duct system is duct board 26.5″ wide 15.5″ tall that runs like an L
around say 13 feet then L then say 75 feet long.
it dips down in the middle then goes back up but its all the same size.
from that flex taps off the box to the vents along the way and at the end they ran a 10″ scoop to 8x8x8 and then 8x6x8 so its two 8 inch and one 6 inch flex at the vary end of the duct board.
its 8- 8″ flex one – 6″ flex and 3 -four inch flex. upgraded from all 6 inch flex.
they installed the new flex all wrong, the inner core is all bundled up in it as it was not stretched.
they used 8 inch round scoop starter collars with a damper, big round sticky gasket on them.
they used sheet metal screws to hold it to the duct board, then the shiny metal back tape, then mastic.
it was installed over dirt caked duct board, 25 years old.
they are all failing off now, tech said the tape might be failing do to mastic getting under the tape?
I first thought it was just two collars and the flex was ok so I cut a 15×15″ peace of 1/4 inch plywood and cut a 8 inch hole in it, I wood screwed the starter collar to the plywood, coated it with mastic and coated
the duct board, taped it to it with the metal tape, so its glued to the duct board, coated the wood with mastic, I just did one.
I told them the whole flex install needs R&R as its all wrong, falling off, not stretching the flex first,
lots of big sags, laying on foundation cement rat hwy. , leaving a 6 inch hole.., pinched 90* bends ect..
I had them come back two times and was told its fixed.
after sending them photos, they want to come back again, and for me to sign a paper saying I am happy after they fix it again?
I told them NO, you are unable to fix it to my satisfaction and all they did on the last fix was bitch and moan, and the fix is wrong on what they did. its that bad. I said ill do it myself, they said they will bring me everything I need, they keep trying to get me to sign off on it.
on the photo I sent I untaped the flex insulation and pulled it back to have about 5 feet of inner flex come out. they got mad and said I was picking apart there work, all that extra flex is fine and it will pass code.
I do not know what to think now?
at first they were going to redo the whole duct system costing 12k for free, but I said no. I thought it was to much and I was surprised by the offer, the cost of my heater/ac was 13k, only the heater went out.
I just wanted the flex upgraded to hard pipe, they showed up with flex.
anyway what starter collars should I use?
the scoop ones or rectangle to round? or other?
do I need to remove my plywood fix? can I use a better material then plywood?
the plywood works quite well, lots of area to seal so no leaks. it does not seem right to me for some reason?
they said the rectangle to round will not get me good CFM’s thats why they did the scoops.
what should I use? I did tell them flex for straight lines only, but no, flex all the way up down u turns,
pinched, bent, massive sags , just taped to collars, boots, ect..
somehow its my fault for inspecting there work? I don’t get it? they offer 12k, I only ask for 3 to 5k of work and they bitch and moan the whole time, half asking it?
I asked is flex to lay on cement like that?, we are not fixing it.
is it to have all thous sag’s? its fine. did u stretch it? yes.
I was told it will be done to calif. standards- what ever that is?
and my photos with questions are to long to read and my wording is scattered.
so I told them I am disabled, dyslexic and heavily medicated, my words do get scattered as you say.
If I can keep getting them to send me messages with, compacted inner core flex is fine, 1,400 cfm rated duct system is fine for a 5 ton ac unit, we do it all the time. ect.. it will give me lots of ammo to fight them with.
I just act dumb, and ask lots of stupid questions, it throws them off so they think they can scam me.
the whole time I am getting them to post, its my fault, its up to code, its done that way ect..
what bothers me is they been doing this for 30+ years, how many neighbors homes are full of holes ect..from there work? I asked them if they were going to inspect the last few jobs they did? NO.
I asked if I can look at jobs they did? NO we can’t let you into other peoples homes.
I am the one with the pissp work done to my home, why are they turning on me? I saved them 8k.
I don’t get it? there management offers me 12k the crew boss tries to cheat me after I turned them down for lesser work? do I want them to try and fix it again? NO. what should I ask for? all supplies and new electric filter and thermostat? I don’t know? got new G9MVE heater 120/78 cost 3500 installed 5 year labor one year service, its a nice heater, clocked the input Btu’s to 200 but;s of nameplate rating.
I need 1800 CFM’s thru 8-8″ flex 3-4″ flex 1-6″ flex thats installed wrong.
heaters second stage is disconnected. 1300 CFM in low.
what starter collars should I use?

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  1. chicken123 | | #1


  2. chicken123 | | #2


  3. chicken123 | | #3

    my plywood fix, I just did one.

  4. chicken123 | | #4

    lots of my phots are to big, got tow on this one.

  5. GBA Editor
    Martin Holladay | | #5

    You have a dispute with your contractor. I have no reason to doubt what you are telling us. That said, this type of complicated dispute is impossible to resolve on a web forum. Clearly, the contractor has visited your house and performed work on more than one occasion.

    You have also performed work in your crawl space to try to fix things. Now everyone is pointing fingers at everyone else.

    One of your sentences surprised me. You wrote, "At first they were going to redo the whole duct system costing 12k for free, but I said no."

    That made me think, "I wonder if there's more going on to this story than what we've heard so far?"

    This type of dispute ends one of two ways. Either (1) you sit down with your contractor and negotiate the best deal you can come up with, in hopes of avoiding a lawsuit (because everyone but the lawyers will lose if someone goes to court), or (2) you sue your contractor. I urge you to take the first path.

  6. walta100 | | #6

    From your photos is look like you duct work is inside the thermo envelope. If that is true then the leaks are irrelevant because all the heated air is staying in the home.

    It seems you accepted a bid for a system made if flexible ductwork and it looks like you got what you paid for. If you are complaining about work that is failing after 12 years of service I am surprised they are even talking to you.


  7. chicken123 | | #7

    thanks, they did the heater and ac uint in 2004.
    the heater failed in oct. my new heater installer pointed out how it was installed wrong.
    it had a cracked cold header.
    I sent the first contractor a letter pointing out how it was installed wrong not expecting anything.
    I was surprised when they called me, they said they want me to be happy(satisfaction guaranteed)
    then they said they would spend 12k to redo the whole duct system.
    I could not except such generosity, the heater/ac was 13k.
    I was planing on fixing just the duct runs myself.
    so I just asked to get my duct systems CFM's up so I can run my new heater in second stage.
    my computer broke the time they showed up, it has my brain on it, so I was lost on weather or not it was right when they were working.
    I am not going to sue anyone, as it was pointed out no one wins.
    I asked them to just bring me what I need, ill do it myself.
    at that point they turned on me?
    they will bring me whatever I need if I sign papers not holding them responsible.
    I might just do that to get the supplies and ill ask for a new thermostat and a new electric filter for me
    doing labor, or is that to much?
    if I do, what starter collars do I want to use?
    I do not know why they offered to do 12k of work?
    my concern is all the other work they done on other homeowners.
    I don't need money. I just want to get 1650 CFM's out of it.

  8. chicken123 | | #8

    I have 12 vents 8-8" 3-4" 1-6"
    the duct system is a pinto, no point in putting racing tires on it.
    I should of had it redesigned for two smaller heaters, but now I have a new heater, so ill have to live with it.
    I did one duct board starter collar fix, and I pulled back the flex insulation on another(photo).
    I am guessing as it is its good for 1200 cfm's.
    I will never get it up enough to run my two stage 5 ton ac unit in second stage, but first stage is fine.
    wife will not let me sign anything.
    I just want to fix it right, ill do it myself, I won't sue anyone, I don't need money, I have common sense,I don't cheat people.
    if say the flex was all 10 inch with all the sags bends ect.. would that say get the same airflow of say 8" run right?
    anyway its not a hard job, and ether way I need to fix it.
    I might just tell them to go away and take the loss.
    so forget about all the above, I need help figuring out what starter collars to use.
    should I remove my plywood to duct board fix?
    thanks for the help.

  9. Expert Member
    Dana Dorsett | | #9

    Not to be throwing gasoline on a brush fire...

    A high stage of 120,000 BTU/hr (in or out) is 3x or more oversized for most houses in the US, 2x oversized even for fairly leaky poorly insulated houses in cold climates. Upsizing the ducts for more cfm to run it at high-stage isn't necessarily what's going to be "right", or provide more comfort (but fixing defective leaking ducts is still a priority.) The better approach for sizing a 2-stage furnace is when the output at low-fire is less than the heat load at the 99% outside design temperature and the high-fire output is a bit higher than the 99% heat load. That way it will run a higher and more comfortable duty cycle when it's cold out, yet still have enough margin at high-fire to stay warm at temperatures below the 99th's percentile temperature bin.

    Since you have a heating history on this place it's possible to take fuel-use against heating degree-day data to measure the actual heat load (including duct losses, etc, since that can't be separated out of the fuel use), and "right size" the heating equipment. For a primer on how to run those numbers see:

  10. chicken123 | | #10

    oh, the duct system is under the house, its set up like a mini basement.
    I close the vents in winter.
    its vary dry in NV 20% humidity.

  11. chicken123 | | #11

    yes the heater is over sized,
    I am at 5200 feet altitude.
    so first stage input is 70,200 second is 108,000k
    this new heater is only downrated at 10% the last one was 20%
    last heater was 93% new one 96%.
    its really a size up from the last one.
    the home is 2600 sq feet, with 18 foot ceilings.
    I can heat the home just fine on first stage, and cool it in first stage 3 ton.
    the windows were just stuck into the cutouts with no flashing or anything, I fixed the bedroom window and
    the outside noise disappeared, before it was like the window was open you could hear everything.

  12. chicken123 | | #12

    I looked up other homes on heater size, I figure a manual J of around 80k to 85k.
    r36 in ceilings r19 in walls 2x6.
    no floor insulation, just r19 around foundation.
    it can get to minus 6 to minus 9 in winter for a few days.

  13. chicken123 | | #13

    last years winter gas bill was 494.00 with 75 gal. hot water heater.
    I have a 10kw sun power solar system, no power bill.

  14. chicken123 | | #14

    I like that heat load, math. I wish I seen it before.
    last year I ran the trane xv90 in first stage only 62,400 Btu's.
    in feb. it was running non stop just barley keeping up.
    my new heater @ around 1300 CFM's static pressure was .9 with the new flex its at .3
    it was set to 1750 CFM's to get the 50* heat rise, its set at 1400 CFM's now and I get the same heat rise.
    so I feel a little better as its now in line with the heart manual, not to exceed .5 static pressure.
    I clocked my gas meter to set the input BTU's, per manual. I asked my last installer about that.
    he said no one does that. I helped him install and set up my new heater, he did a lot for 900.00.
    he was so impressed my my skills he offered me a job, to be his top worker/installer.
    he was a rare contractor/ working with me ect.. I intimidate most people with my skills.

  15. Expert Member
    Dana Dorsett | | #15

    With the fuel-use load math you don't have to derate for altitude. (In fact for most newer burners there is no derating necessary at only 5200' anyway, even if the manuals say you do, but that's another story.)

    A Manual-J of 80,000 BTU/hr @ -10F for a 2x6/R19 house would be either one of the air-leakiest 3000' houses in CO, or something with a huge amount of glass area, or a much larger house. (Your 99th percentile temperature bin is more likely to be in low negative single digits: ) A right-sized single-stager SHOULD run nearly non-stop during cold weather near the 99% outside design temperature, barely keeping up, but keeping up nonethelless. If a ~62K furnace is still keeping up and running an 80% duty cycle, the actual 99% design heat load (including duct losses) would be on the order of 50K.

  16. chicken123 | | #16

    I guessed at the manual J, I looked up other 2500 sq foot homes in my area that had it done.
    I forgot where? but the home that I was going off was manual J 83k and it did not have vaulted ceilings.
    my home is a can of worms, custom ranch style single story home, vaulted ceilings 3 bed 2 1/2 bath.
    2584 sq feet.
    it was built in 1989, the 5 acre lot with well was 40k, and they built it for a total price of 150k with land.
    the builder was a sheet rock installer, the sheet rock in the home is done vary nice.
    it was sold in the early 90's for 180k the prior owner put about 80k into landscape he added a 6 car garage attached to the rv garage in the back yard, it also has an oversized 3 car attached garage.
    I got it for 260k in 98 now worth 650k. but I would not pay 650k.
    last summer when painting, I wanted to replace the front windows.
    thats when I seen the worms, the siding is the pressboard recalled siding, no gaps between them,
    the windows were just slapped in no flashing/none.
    there is no tare paper behind the siding, my old roof blew off about 14 years ago, it was some pressboard type only made in 88, so I got a new presidential shake roof lifetime warrantee 50 year transferable,28k.
    insurance payed for it. it does not have flashing ether.
    it has blown in insulation @ r36, the walls r19., I have a 3700 sq foot cement driveway (needs replacing)
    wife wants pavers?(not worth the cost to me?) but stamped cement is 60k. pavers over 100k.
    its pavers or nothing to her so its nothing.
    and the heater went out with a cracked cold header, not sure what caused it to crack?
    it could of been the 2 inch exhaust pipe, needed 3, it was leaning back several inches, it was over fired,
    #45 jets needed #47, in first its rated at 62,400 but was at around 75k, ect..
    I just never really looked at anything. I should get a real home inspection, all contractors here are really bad. just people off the streets with no skills. so you have to fix it yourself.
    I been really sick for the last 10 years, but I am feeling better this year.(feeling better after new heater was installed) co poisoning? can the inducer type heater leak CO into homes?
    heater is in garage.
    it was really cold last feb, minus 9 -is when it was running 24/7 set at 70* the temp fell down to 68 in early morning then back up to 70* I should of got an 80k heater that would of been 72k downrated.
    I got a two stage do to having a trane 19i 5 ton two stage ac unit 19 seer.
    I do not think at 70k BTU it could heat up the home say from 60 to 70 in a timely manor,
    but if its always set to 70* no prob.
    I believe my home is a sieve full of leaks.
    it says we are in zone 5 but plants rated for zone 4 die off do to cold weather.
    only zone 3 plants survive here.
    gas is cheap now around .35 a therm. it did get up to 1.25 a therm years ago.
    but its all to late now, I got a new heater, should of did a combo electric, gas and pellet stove.
    I have an air tight wood stove but don't use it as one room is 80* the rest are 60* when used.
    and wood went from 75 a cord to 300.
    but the new heater is running around "output" 66,700 BTU's in first. and it seems just right.
    gas=.60 gravity 900 Btu's per cubic foot, meter clocked at 46 seconds for one cubic foot.
    it went up to 48 seconds so I readjusted it back to 46 sec. I'm thinking the cold weather/cold gas might have something to do with it? I check it every billing period with the Billings BTU rating.
    with the tall ceilings I figure its like a 3500 sq foot home for heating.
    the home is 90 feet long. it only had one 20x30 filter x 20 inch return but now I have a 14/24 -14 inch flex pipe return by the bedrooms. I have lots of work to do on this boat.
    heater size is hard to pick, if you are home all the time and keep the thermostat set to 70* all the time,
    a small heater is fine. if you are gone all the time and set the thermostat to 60* then when home up to 70*
    you want the two stage 78/120 downrated 70/108. to heat up the home faster.
    it takes a long time for the temp. to go up when on first stage when its cold out.
    I don't get that my water heater is good up to 10k feet but the furnace needs different jets?
    I am setting up this heater perfect per manual, I want to see how long it will last if its set up/serviced per manual. it does say input BTU's must be within 2% of nameplate rating or the heat exchanger will fail.
    the gas BTU's can change over that limit monthly. 875 to 925 btu's per cubic foot.
    I have the input Btu's almost perfect. gas meter tested by power company once a year to.
    heater is level it has 35 equivalent feet of 3 inch exhaust #45 jets all perfect per manual.
    static pressure says .2 to .5 its at .3 now. heat rise 30 to 60 in first stage its at 50*.
    everyone I asked who has the 92% to 96% heaters say they last 10 years.
    I believe is do to over firing, not clocking the gas meter. I will soon find out in 10 to 30 years if it makes any difference. by then everyone will be using heat pumps.

  17. chicken123 | | #17

    photo of home layout

  18. chicken123 | | #18

    google map photo.

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