Wussup guys
I am planning to redo some of my duct work for 5 reasons.
-Condensation on ducts connection
-Possible undersized duct work as indicated by loud air handler when on 2nd stage
-More Airflow overall
-Possible smaller plenum then should be and a new, bigger maybe needed
-increase some pressure to my family room downstairs which is furtherest from air handler
My air handler is a York 4 ton Mv16cn21H and Condenser Czh04811B with 2 stage compressor with Honeywell IAQ tstat. I currently have the cfm on 1350 high and 860 low because the noise is annoying when the unit runs full speed. I should be 1600 cfm. I am also thinking of putting it on 1700 cfm after I do the duct work.
I am going to break down my layout of my ducts and what I want to do and you guys can give me some feedback.
Plenum starts off the width of the air handler 21" x 21" then it transition to my old plenum which is 16" width by 21" length. The transition is about 10" inches.
As the plenum starts to go up toward the attic maybe 1 ft up, the interior wall on left side of the air handler has a 15"x12" rectangular duct enclosed behind the interior wall. That duct runs down to my first floor and it then connects to all the vents downstairs which are inside the ceiling.
As the plenum goes up to the attic it has 2 main flex duct trunklines . I don't know the exact sizes but either they are 10" or 12" ducts. I measured the duct all around and it came out about, I think if I remember correctly 42".. I guess you call that the diameter of it? lol I don't remember my geometry so well. The trunklines run each about 12 ft.
At each end of the trunkline there is a triangle shape mixer box measured 20x20x16 and 15" deep. On one triangle box I have these flexducts hooked up
1- Main trunk line 10" or 12"
1- 4 inch flexduct that goes to bathroom
1- 6" duct to one bedroom
1- 6" duct to another bedroom
Those two - 6" ducts lol seems to be connected on one side of the triangle box and it seems like they are sharing the connection.
The other Triangle box has the following ducts hooked up.
1- Main trunk line 10" or 12"
1- 4 inch flexduct that goes to bathroom
1- 4 inch flexduct that goes to walk-in closet
1- 8 inch flexduct for the master room
Now other then that there is one 6" flex duct hooked up directly to my plenum that was added to the master room when I had the new system installed.
Also there is another room next to master room and it has a 6" duct also but that one feeds off the main trunkline that runs to master room. Its weird because the main trunk line doesn't hook up to a triangle box first and then give the 6" duct feed to that room. But instead there is a point where the maintrunk line makes a 90' turn and at that turn there is a junction formed and the 6" duct gets a feed from there and then the main trunkline continues to the triangle mixer box. I have attached 2 layouts for you guys to see all that I have described.
Ok my questions now
1. Is it worth it for me to make a new plenum that sizes with the width of the air handler and will run up to attic 21" x 21 " ? My current plenum also has some mold forming due to the condensation problem, so I kinda of have more reason to rip out the old plenum and make a new one.
2. When I make the new trunklines I am going to have my contractor use R6 1 1/2" ductboards but how should I have him size them? Is 10x8 rectangular duct good size trunk lines? I was told to use the ductboards as they are good in dealing with the noise issue I have. (I am planning to use the ductboards for both plenum and the trunklines) I can also tell you this I did do a heating and cooling load with Hvac- cal 4.0 and it said I need about 900 cfm downstairs and 700 cfm upstairs. I am glad I got that 15x12 duct running downstairs as that probably sends down plenty of air. I just may have to check when that 15x12 duct reaches downstairs how does it connect to the ducts as some vent's pressure are not that strong. Especially my family room the airflow pressure is low there. I am planning to cut a small portion of my ceiling where that 15x12 duct comes down to the first floor so I can see how that 15x12 duct connects the other ducts. I hope there is no triangle boxes there too! I will probably let you guys know what is there after I cut the ceiling.
3. What other feedback you guys have for me? Do you guys think changing my ductwork will help with the noise problem I have?? Can you guys tell from my current ductwork sizes if the ductwork is undersized for the unit? I understand about the condensation problem I have and that they need to be sealed up. I already have RCD mastic on hand to do that but I will do it after the new ducts are up. I also believe this may help give me much better airflow overall.
Check out my attachment and let me know what everybody thinks and if this is a good idea. The pdf file named ductworks is how my duct work is in my attic.
I am planning to redo some of my duct work for 5 reasons.
-Condensation on ducts connection
-Possible undersized duct work as indicated by loud air handler when on 2nd stage
-More Airflow overall
-Possible smaller plenum then should be and a new, bigger maybe needed
-increase some pressure to my family room downstairs which is furtherest from air handler
My air handler is a York 4 ton Mv16cn21H and Condenser Czh04811B with 2 stage compressor with Honeywell IAQ tstat. I currently have the cfm on 1350 high and 860 low because the noise is annoying when the unit runs full speed. I should be 1600 cfm. I am also thinking of putting it on 1700 cfm after I do the duct work.
I am going to break down my layout of my ducts and what I want to do and you guys can give me some feedback.
Plenum starts off the width of the air handler 21" x 21" then it transition to my old plenum which is 16" width by 21" length. The transition is about 10" inches.
As the plenum starts to go up toward the attic maybe 1 ft up, the interior wall on left side of the air handler has a 15"x12" rectangular duct enclosed behind the interior wall. That duct runs down to my first floor and it then connects to all the vents downstairs which are inside the ceiling.
As the plenum goes up to the attic it has 2 main flex duct trunklines . I don't know the exact sizes but either they are 10" or 12" ducts. I measured the duct all around and it came out about, I think if I remember correctly 42".. I guess you call that the diameter of it? lol I don't remember my geometry so well. The trunklines run each about 12 ft.
At each end of the trunkline there is a triangle shape mixer box measured 20x20x16 and 15" deep. On one triangle box I have these flexducts hooked up
1- Main trunk line 10" or 12"
1- 4 inch flexduct that goes to bathroom
1- 6" duct to one bedroom
1- 6" duct to another bedroom
Those two - 6" ducts lol seems to be connected on one side of the triangle box and it seems like they are sharing the connection.
The other Triangle box has the following ducts hooked up.
1- Main trunk line 10" or 12"
1- 4 inch flexduct that goes to bathroom
1- 4 inch flexduct that goes to walk-in closet
1- 8 inch flexduct for the master room
Now other then that there is one 6" flex duct hooked up directly to my plenum that was added to the master room when I had the new system installed.
Also there is another room next to master room and it has a 6" duct also but that one feeds off the main trunkline that runs to master room. Its weird because the main trunk line doesn't hook up to a triangle box first and then give the 6" duct feed to that room. But instead there is a point where the maintrunk line makes a 90' turn and at that turn there is a junction formed and the 6" duct gets a feed from there and then the main trunkline continues to the triangle mixer box. I have attached 2 layouts for you guys to see all that I have described.
Ok my questions now
1. Is it worth it for me to make a new plenum that sizes with the width of the air handler and will run up to attic 21" x 21 " ? My current plenum also has some mold forming due to the condensation problem, so I kinda of have more reason to rip out the old plenum and make a new one.
2. When I make the new trunklines I am going to have my contractor use R6 1 1/2" ductboards but how should I have him size them? Is 10x8 rectangular duct good size trunk lines? I was told to use the ductboards as they are good in dealing with the noise issue I have. (I am planning to use the ductboards for both plenum and the trunklines) I can also tell you this I did do a heating and cooling load with Hvac- cal 4.0 and it said I need about 900 cfm downstairs and 700 cfm upstairs. I am glad I got that 15x12 duct running downstairs as that probably sends down plenty of air. I just may have to check when that 15x12 duct reaches downstairs how does it connect to the ducts as some vent's pressure are not that strong. Especially my family room the airflow pressure is low there. I am planning to cut a small portion of my ceiling where that 15x12 duct comes down to the first floor so I can see how that 15x12 duct connects the other ducts. I hope there is no triangle boxes there too! I will probably let you guys know what is there after I cut the ceiling.
3. What other feedback you guys have for me? Do you guys think changing my ductwork will help with the noise problem I have?? Can you guys tell from my current ductwork sizes if the ductwork is undersized for the unit? I understand about the condensation problem I have and that they need to be sealed up. I already have RCD mastic on hand to do that but I will do it after the new ducts are up. I also believe this may help give me much better airflow overall.
Check out my attachment and let me know what everybody thinks and if this is a good idea. The pdf file named ductworks is how my duct work is in my attic.