HELP, Dash or Plainspoken, anyone.

I have been reading this thread until I am exhausted.

Titan my hats is off to you sir, you must be the most patient and kind person a service company could run into.

My opinion is the installing company hasn't had an training on this system or slep thru class if they did.

All the rhetoric of changing out parts and waiting for parts is just ridiculous! 1st this is classified as a parts changer, their not trouble shooting the problem for lack of knowledge, just guessing our unquailified you pick.

I read you've been dealing with the distributor US-Air, I assume Anaheim, or perhaps City of Industry. Do these guys know about the parts changing?

Excuses on parts not in are unacceptable, but not that it really mattered anyway when they go the new parts. When I place an order with my salesman at Us-Air I know location of the parts I am geting and when they will be here...

I would definately get the second opinion with a Carrier dealer that is familar with the Infinity System only. Check their creditials with US-Air Carrier sales rep, good luck

It is most regrettable that you have experienced any problem with such a beautiful system. But whats more regrettabe is that you learned in the11th hour your isntalling contractor doesn't have the experience and training to be servicing your equipment.

Tinner73,

Thanks for looking at the photos. I know this is not perfect but this was same layout as the original AB ductwork. I agree with you but with the design of the home there really is not another option. There is no other way to get ducts to the Kitchen, Dinning room and living room from the garage without going to the attic unless I was to run exposed duct work on the inside of finished walls in the living space. Do you think that increasing the size of the flex to 8" would help, or is the flexduct going to continue to cause this issue? If I have them replace the flex and put metal ductwork in am I still going to have a return issue?

ESP is currently running at .27 @ 825CFM in low heat and .46-.47 ESP @ 1025 CFM in high heat.

ESP is running at .77-.78 @ 1468 CFM in high cool.

Esp is running at .29 @ 882 CFM in low cool.

These don't seem too high over the spec by Carrier of .50 ESP.

Since I removed the circular dampner form the 9" duct I have not had a "33 limit circuit fault" with the heat on.
Since this reduced ESP maybe it's fixed?

thanks!

Quote:

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Originally posted by titan7
Tinner73,

Thanks for looking at the photos. I know this is not perfect but this was same layout as the original AB ductwork. I agree with you but with the design of the home there really is not another option. There is no other way to get ducts to the Kitchen, Dinning room and living room from the garage without going to the attic unless I was to run exposed duct work on the inside of finished walls in the living space. Do you think that increasing the size of the flex to 8" would help, or is the flexduct going to continue to cause this issue? If I have them replace the flex and put metal ductwork in am I still going to have a return issue?

ESP is currently running at .27 @ 825CFM in low heat and .46-.47 ESP @ 1025 CFM in high heat.

ESP is running at .77-.78 @ 1468 CFM in high cool.

Esp is running at .29 @ 882 CFM in low cool.

These don't seem too high over the spec by Carrier of .50 ESP.

Since I removed the circular dampner form the 9" duct I have not had a "33 limit circuit fault" with the heat on.
Since this reduced ESP maybe it's fixed?

thanks!

---

With the damper removed from the 9" ,you will likely have low air flow to the second floor in cooling.Warm air rises,so now the extra air to the first floor ,rises to the second floor.Cool air falls,so the second floor will likely be lacking air flow again.


The reason I asked about adjoining rooms was,if a room adjoins the furnace area ,a thru the wall supply could be added(similar to the 9"),seems like that won't work.If you droped the ceiling in the adjoining bath,would that allow a sidewall supply to a larger room??If it would this would reduce the air that now travels thru the 14" duct ,and thus the Static.


The 14" likely needs to be an 18" flex duct ,to reduce the static,maybe reduced to a 16" after the first few takeoffs.A Man.J needs to be done to determine the correct size runs for all the rooms.A square to round ,metal fitting from the coil to the now 14" duct,would help also.


If they can't increase the 14" thru the ceiling,due to framing,increase it as soon as framing allows,using a metal "increaser" 14" to 18" round.





Check to be sure the "hole " in the stand is cut to the size of the filter,not smaller.

You ducts are undersized,changing them to metal would not likely solve the problem.

Thanks Dash, those are great suggestions.

I will not be able to drop the ceiling in the Bath as it's only about about 7' high now. it's only 5 wide by 9feet long, toilet and sink, with a exshast fan in the middle of the ceiling.

On the 14" the soonest an 18" could be fitted is in the attic just as it comes out of the framing.

With regard to the hole on the platform, the hole is the same size as the intake of the furnace. We were going to use the smaller filter rack at first so they told me to cut out the hole to the Furnace specs. During the install the smaller honeywell rack did not fit right so they went with the larger 20x25" rack. I the entire furnace,coil etc would need to be disconnected and removed for that option. If we are doing that I would also have the entire platform redesigned.

What about running another supply to the opposite side of the wall where the 9" is going in. I was thinking could be run externally in on the ceiling of the garage and to the right of the furnace and going through the wall above the washer and dryer? On the inside wall it would look like the duct above my wine frig only 10 feet to the left? If if was return it would have to enter the platform from the side(cut through the drywall) I am not sure that would be to code.

Quote:

---

Originally posted by titan7
Thanks Dash, those are great suggestions.

I will not be able to drop the ceiling in the Bath as it's only about about 7' high now. it's only 5 wide by 9feet long, toilet and sink, with a exshast fan in the middle of the ceiling.

On the 14" the soonest an 18" could be fitted is in the attic just as it comes out of the framing.

With regard to the hole on the platform, the hole is the same size as the intake of the furnace. We were going to use the smaller filter rack at first so they told me to cut out the hole to the Furnace specs. During the install the smaller honeywell rack did not fit right so they went with the larger 20x25" rack.



?????
I the entire furnace,coil etc would need to be disconnected and removed for that option.?????


If we are doing that I would also have the entire platform redesigned.

What about running another supply to the opposite side of the wall where the 9" is going in. I was thinking could be run externally in on the ceiling of the garage and to the right of the furnace and going through the wall above the washer and dryer? On the inside wall it would look like the duct above my wine frig only 10 feet to the left? If if was return it would have to enter the platform from the side(cut through the drywall) I am not sure that would be to code.

---

The extra run would help,only if it feeds a different room,than the existing 9" .


If the bath ceiling is 7',has it ben dropped already,could there be a dead space above it,for a duct run??

[QUOTE]Originally posted by tinner73

Quote:

---

Originally posted by titan7

4. If two stories,what feeds the down stairs??
Just that 9" in the family room, Up in the attic they run three 6" flex lines to the other side of house in the attic and down the stairwell to the livingroom, dinning room, and kitchen. Bad design but this was what the original ductwork did.


i think this is your problem. if i understand right, the 6" ducts run across the attic AND then down the stairwell. i'm sorry to say but you have a horrible duct system in your house. it is by far the cheapest to install and the worst for airflow. if all your ducts were smooth insulated metal you would have better airflow.

---

Well better airflow minus the up to the 40% leakage you can have with those smooth insulated tin ducts....

But I will not argue the duct design and sizing seem inadequate.

There may be room for a small 5-6" duct, which would terminat toward the living room. in the hallway, that duct would be 12 feet away form the 9". Would adding another return to the same room as the 9" be a solution or code violation.




AllTemp,
Yes it was US-Air in the City of Industry and yes they knew about the issues.

By the way,

Are these ESP readings ok:

ESP is currently running at .27 @ 825CFM in low heat and .46-.47 ESP @ 1025 CFM in high heat.

ESP is running at .77-.78 @ 1468 CFM in high cool.

Esp is running at .29 @ 882 CFM in low cool.

These don't seem too high over the spec by Carrier of .50 ESP.

Since I removed the circular dampner form the 9" duct I have not had a "33 limit circuit fault" with the heat on.
Since this reduced ESP maybe it's fixed?


[Edited by titan7 on 01-17-2005 at 11:47 AM]

Quote:

---

Originally posted by titan7
There may be room for a small 5-6" duct, which would terminat toward the living room. in the hallway, that duct would be 12 feet away form the 9". Would adding another return to the same room as the 9" be a solution or code violation.




AllTemp,
Yes it was US-Air in the City of Industry and yes they knew about the issues.

By the way,

Are these ESP readings ok:

ESP is currently running at .27 @ 825CFM in low heat and .46-.47 ESP @ 1025 CFM in high heat.

ESP is running at .77-.78 @ 1468 CFM in high cool.

Esp is running at .29 @ 882 CFM in low cool.

These don't seem too high over the spec by Carrier of .50 ESP.

Since I removed the circular dampner form the 9" duct I have not had a "33 limit circuit fault" with the heat on.
Since this reduced ESP maybe it's fixed?


[Edited by titan7 on 01-17-2005 at 11:47 AM]

---

Titan,

I don't see it as fixed,other than for heating.

I thought you stated that the damper in the 9" was needed to get enough air to the second floor for cooling.If so you are okay for now ,but what about this summer.

What condition is your filter,currently when reading the static,if it's clean,it's still to high in cooling,if it's dirty the static is marginal.

The duct you could run above the bath,doesn't have to be round ,could be ,say a 5'X10",which is almost equal to an 8" round.If it can be done ,and will blow enough to cool the living room,and is located close enough to it,you will need to close off the existing supply in the living room,so that less air (air for living room) has to travel thru the existing duct(14").This will reduce the static,maybe not enough,can't tell from here.


I'd be very concerned about getting it fixed now,instead of waiting till the summer,and higher cooling cfm's.

They should take the static of the supply and return separately,if they do ,I think you'll find the supply is the major problem.

[QUOTE]Originally posted by thehumid1
[B][QUOTE]Originally posted by tinner73

Quote:

---

Originally posted by titan7




Well better airflow minus the up to the 40% leakage you can have with those smooth insulated tin ducts....

But I will not argue the duct design and sizing seem inadequate.

---

you're kidding right...40%?? why couldn't you seal the metal ducts as well? 40% where do you come up with this? we have to smoke test our ductwork (commercial) all the time, up to 6". SIX INCHES!!! so it can be sealed, i think you could get .5", duh, if you take the time. maybe YOU have 40% leakage. this poor system was doomed from the begining. what it needs is a metal graduated trunkline that is properly sized/insulated.


SMOOTH is always better for "flow", ALWAYS. metal duct is smooth, flex is not. a surface that is not smooth (flex) causes excessive DRAG on the air. that is why ALL other pipe is smooth, gas, ACR, conduit, water,etc.

I don't agree with 40% leakage of metal,being the norm either.

However it's wrong to imply that flex can't be sized properly to deliver the same amount of air as metal.Agreeded the flex ducts will be larger than the metal ducts.More importantly the air flow will be the same.

As Dash already said:

However it's wrong to imply that flex can't be sized properly to deliver the same amount of air as metal.Agreeded the flex ducts will be larger than the metal ducts.More importantly the air flow will be the same.

So your statement was misleading....

OR IN YOUR OWN WORDS:
? 40% where do you come up with this? we have to smoke test our ductwork (commercial) all the time, up to 6". SIX INCHES!!! so it can be sealed, i think you could get .5", duh, if you take the time. maybe YOU have 40% leakage. this poor system was doomed from the begining.

what it needs is a metal graduated trunkline that is properly sized/insulated.

OR WHAT IT NEEDS IS A FLEX DUCT SYSTEM THAT IS PROPERLY SIZED AND INSULATED....

Smoke testing is nice but using the DELTA Q method with a blower door test is the best for residential as it can give the amount of duct loss occuring while the system is at normal operating conditions with the blower on.. as oppposed to a ductblaster test which only reveals leaks at a given pressure by that machine.

40%??? I am not making it up MJ8 allows for this percentage so it must exist. In their October 13 2003 input to the Florida Energy Committee they stated loads could be doubled..."However, placing loosely-sealed, un-insulated duct in the same unconditioned attic can double the needed equipment capacity..."

They then went to further defend themselves against claims that the duct loads cause oversizing by 200-400% for all dwellings they sugested this was not true. But Welguisz who was disputing them was using Table 7B-TS which was not indicative of most of the ductwork used in Florida(flex).

Their comment was:
"a) ACCA Table 7B-TS applies to duct system that has a large amount of duct surface area(trunk runs in the center of an attic with run-outs to supply outlets at the perimeter of the cieling plan) so it has proportionally large leakage and conduction gains."

Yet isn't this is exact kind of duct system you are suggesting for this post? The one with the most duct surface area and proportionally larger leakage and conduction gains?

That said " properly designed,installed, and insulated of either material will be equal in performance."

They both have pros and cons but it is misleading to state that flex is "worst for airflow" which is true only if improperly sized....when properly sized it can achieve or exceed any Mfr's static pressure requirements.

Just like 40% duct loss on your smooth metal duct is highly unlikey although is possible if improperly installed and uninsulated.

The best thing to do is a Man. J,to determine the CFM needed per room and then Man. D to redesign the ducts.

Since that may not happen,you could split the 14" in the attic ,close to the plenum,into a 14to14to14 wye.attach existing 14 to one and another 14to the other,run the new 14 to the other side of the house to feed those downstairs runs.Cap those runs off from the existing 14.

Install hand dampers at each 14 from the Wye,to balance the airflow.Install a damper in that 9" run,to balance the air flow.

This should get the cfm down to an exceptable level.Try suggesting this to the installing contractor.

Be aware that the Infinity,can "decide" to run at 400cfm per ton at times,so under certain conditions ,at 1600 cfm the static may stil be to high.I'm unsure of what tells it to do this,but we have noticed it shortly after start up on new jobs,were the stat is set well below the room temperature.