Expert duct work replacement installation advise in South Florida
Looking to have A/C ductwork replaced on a 1100 SF house (2 bedroom house) currently have plenum with all ducts attached to it leaving no room for additional lines. Was told I Need to have plenum replaced with main line with ducts attached to the main line. Currently have 8 vents and two returns. Must be knowledgeable in HVAC and Ducts since my attic space is no joke.
Seriously,I need my duct work replaced (its about 25 years old) since my AC’s have been replaced over the years except the duct work and all AC’s have struggled through the summer, along with advise convinces me it’s time to get the duct work replaced. Thanks-
Back story - over the years we’ve replaced the A/C several times and have always had cooling issues during the summers even after better AC’s installed. Was told by one company the existing ducts all connected at plenum. The guy said I need a plenum, one main line running down length of house with vents attached to it. Referred me to someone, but this was years ago and lost contact.
Southeast or Southwest FL???
What are the problems, hot spots or humidity?
Regards Teddy Bear
Bear Rules: Keep our home <50% RH summer, controls mites/mold and very comfortable.
Provide 60-100 cfm of fresh air when occupied to purge indoor pollutants and keep window dry during cold weather. T-stat setup/setback +8 hrs. saves energy
Use +Merv 10 air filter. -Don't forget the "Golden Rule"
Hire a company with experience in duct design.
Do have your house examined to see how it can be tightened for more energy efficiency. A blower door test can be very helpful for this.
Also consider removing the ceiling insulation and getting he bottom of the roof deck insulated with spray foam. Doing so will put the ducts INSIDE the conditioned space which reduces the load.
Check the links in my sig to find experts in your area.
********* https://www.hvac20.com/ High efficiency equipment alone does not provide home comfort and efficiency. HVAC2.0 is a process for finding the real needs of the house and the occupants. Offer the customer a menu of work to address their problems and give them a probability of success.
Find contractors with specialized training in combustion analysis, residential system performance, air flow, and duct optimization https://www.myhomecomfort.org/
Southeast or Southwest FL???
What are the problems, hot spots or humidity?
Regards Teddy Bear
No hot spots, just during the summers, my A/C struggles to keep 76-77 and runs non stop. I tried to have extra vents put in and was told all vents attach to plenum and there was no room to attach more. I was also told that from the plenum, I need a main line with all vents attached to the mainline. As it is now, the air handler is in one of the two bedrooms so the bedroom are always cold - was told I couldn’t restrict air flow from bedroom vents so other vents in house will blow harder.
I know my attic is tight - maybe a few feet at most. My issue is having someone tell me they can do it. I’d never know because it’s in attic. It takes a special person to install ducts here in southeast Florida (Ft Lauderdale)
No hot spots, just during the summers, my A/C struggles to keep 76-77 and runs non stop. I tried to have extra vents put in and was told all vents attach to plenum and there was no room to attach more. I was also told that from the plenum, I need a main line with all vents attached to the mainline. As it is now, the air handler is in one of the two bedrooms so the bedroom are always cold - was told I couldn’t restrict air flow from bedroom vents so other vents in house will blow harder.
I know my attic is tight - maybe a few feet at most. My issue is having someone tell me they can do it. I’d never know because it’s in attic. It takes a special person to install ducts here in southeast Florida (Ft Lauderdale)
Just really looking for one or two extremely skinny people who knows duct installation
Just really looking for one or two extremely skinny people who knows duct installation
Installers are NOT designers. Be prepared for uneven delivery and temperatures.
********* https://www.hvac20.com/ High efficiency equipment alone does not provide home comfort and efficiency. HVAC2.0 is a process for finding the real needs of the house and the occupants. Offer the customer a menu of work to address their problems and give them a probability of success.
Find contractors with specialized training in combustion analysis, residential system performance, air flow, and duct optimization https://www.myhomecomfort.org/
I had a A/C company check my system and suggested the duct work be replaced. He looked at my existing returns and thought they looked good and were sealed. He asked if it was dusty which it is more than ever and said that’s a sign of old duct work. He suggested adding a return to each bedroom and living room along with replacing all other existing duct work.
I had a A/C company today check my system and suggested the duct work be replaced. He looked at my existing returns and thought they looked good and were sealed. He asked if it was dusty which it is more than ever and said that’s a sign of old duct work. He suggested adding a return to each bedroom and living room along with replacing all other existing duct work.
Also, found out it’s not at all a slow time down here for A/C work. I thought this would be the perfect time because it’s cooler out.
Last edited by johnml; 01-14-2021 at 02:36 PM.
Reason: Delete duplicate post
Were any measurements taken? Air Flow not physical? You need a contractor that will perform a Total External Static Pressure (TESP) test. With that they can tell how much air the ducts can handle and where improvements can be made. Supply, return and or both.
Running non stop at design conditions is expected. 76-77°F, what's the RH at that time? If the RH is high a Whole House dehumidifier may be in order. If the home is leaking bringing in outside air can help with that.
Sounds like all your getting is salesman and guesses
No hot spots, just during the summers, my A/C struggles to keep 76-77 and runs non stop. I tried to have extra vents put in and was told all vents attach to plenum and there was no room to attach more. I was also told that from the plenum, I need a main line with all vents attached to the mainline. As it is now, the air handler is in one of the two bedrooms so the bedroom are always cold - was told I couldn’t restrict air flow from bedroom vents so other vents in house will blow harder.
I know my attic is tight - maybe a few feet at most. My issue is having someone tell me they can do it. I’d never know because it’s in attic. It takes a special person to install ducts here in southeast Florida (Ft Lauderdale)
Without hot spots and only very slightly undersized, what is the proof of undersized ducts.
As you increase the air flow, sensible cooling increases but latent cooling declines. This means that the %RH will rise. High %RH is a big problem.
If it was mine, I would live with the problem 77^F and <50%rh. If you find the 77^F unacceptqble but %RH 45-50, increase the capacity of outdoor unit. Another check is to measure the pressure drop a/c blower intake and supply. All air handlers have specs to meet.
As you incrrease air flow, Sensible cooling capacity increases and moiture removal decreases. Expect more moisture in the air as you fix this problem by increasing the air flow.
Keep us posted.
Regards Teddy Bear
Bear Rules: Keep our home <50% RH summer, controls mites/mold and very comfortable.
Provide 60-100 cfm of fresh air when occupied to purge indoor pollutants and keep window dry during cold weather. T-stat setup/setback +8 hrs. saves energy
Use +Merv 10 air filter. -Don't forget the "Golden Rule"
I got a real good friend in ft lauderdale who maybe able to help. He is a installer/ tech. We did some work together when I lived in Miami. The problem sometimes is if you cant get into the attic easily then most installers will say its not possible. You may have to open the ceiling to get any real work done correctly. Use R8 ducts. Also I don't know if its possible but you can try mini splits as a option. My email is my profile and I can email you his number.
Looking to have A/C ductwork replaced on a 1100 SF house (2 bedroom house) currently have plenum with all ducts attached to it leaving no room for additional lines. Was told I Need to have plenum replaced with main line with ducts attached to the main line.
Currently have 8 vents and two returns.
Must be knowledgeable in HVAC and Ducts since my attic space is no joke.
Seriously,I need my duct work replaced (its about 25 years old) since my AC’s have been replaced over the years except the duct work and all AC’s have struggled through the summer, along with advise convinces me it’s time to get the duct work replaced. Thanks-
Is house 25 years or 50 years old.?
Roof pitch 2/12 or 4/12 ?
Designer Dan __ It's Not Rocket Science, But It is SCIENCE with Some Art. _ _ KEEP IT SIMPLE & SINCERE ___ __ www.mysimplifiedhvac.com ___ __ Define the Building Envelope & Perform a Detailed Load Calc: It's ALL About Windows & Make-up Air Requirements. Know Your Equipment Capabilities
I got a real good friend in ft lauderdale who maybe able to help. He is a installer/ tech. We did some work together when I lived in Miami. The problem sometimes is if you cant get into the attic easily then most installers will say its not possible. You may have to open the ceiling to get any real work done correctly. Use R8 ducts. Also I don't know if its possible but you can try mini splits as a option. My email is my profile and I can email you his number.
hello how to get in touch with your friend in miami/fort laud