Replacing HVAC ductwork

[rapmarks]

Interesting never heard of this but apparently in Florida it is common to have to replace the ductwork after 15 or 20 years
I do not recall this ever happening up a north.
I think about mine up north; it is between two finished floors.but in Florida, it is in a pretty small attic space.
Has anyone had their ductwork replaced?

 

[TUGBrian]

what is the reason they want it to be replaced? what sort of duct work?

ive had a single large run replaced before but only because it had ruptured.

id spend money on more insulation and or resealing the joints at the registers before id replace duct work that wasnt leaking.

 

[davidvel]

Never heard of replacing duct work on a schedule. Sounds like a TS sales job. "You need it."

 

[TUGBrian]

big scam here in florida is the ductwork "cleaning".

 

[rapmarks]

My first response was it was a scam, but several homeowners I know responded that they had to replace because the ducts deteriorated and leaked.

 

[emeryjre]

A response to the question from Microsoft CoPilot

Yes, heating and cooling ductwork can rust out in Florida, and it's actually a fairly common issue due to the state's climate and environmental conditions. Here's a breakdown of why it happens and how to prevent it:

Why Ductwork Rusts in Florida​

• High Humidity: Florida’s tropical climate means consistently high humidity levels, which introduce moisture into HVAC systems and promote rust formation.
• Condensation: Moisture often condenses on evaporator coils, pipes, and inside ducts, especially if insulation is missing or damaged.
• Water Leaks: Leaky duct connections or poorly drained condensate pans can allow water to pool inside the system.
• Salt Exposure: Coastal areas in Florida expose ductwork to salty air, which accelerates corrosion, especially on metal surfaces.

Materials and Vulnerability​

• Galvanized Steel: Commonly used in ductwork, but it can corrode if the protective zinc coating wears off or if exposed to moisture without proper insulation.
• Underground Ducts: These are especially vulnerable unless properly sealed and protected, as required by Florida Building Code.

Prevention and Maintenance Tips​

• Seal Leaks: Ensure all duct joints and seams are properly sealed to prevent moisture intrusion.
• Dehumidifiers: Installing a whole-house dehumidifier can help control indoor humidity levels.
• Routine Maintenance: Regular inspection and cleaning of condensate pans, drains, and ductwork can catch early signs of rust.
• Protective Coatings: Applying rust inhibitors or coatings to metal ducts can slow corrosion.
• Insulation: Proper insulation prevents condensation and protects against temperature fluctuations.

Risks of Rust​

• Efficiency Loss: Rust can reduce airflow and HVAC efficiency, increasing energy costs.
• Health Concerns: While rust flakes themselves aren’t usually harmful, they indicate moisture that can lead to mold and bacterial growth.
• System Damage: Left untreated, rust can lead to duct failure and costly replacements.

If you're setting up or maintaining HVAC systems in Florida, especially in coastal or high-humidity areas, proactive rust prevention is essential.

 

[PigsDad]

All of our ductwork in our Florida home is flexible non-metal piping. No rust issues with that stuff.

Kurt

 

[dioxide45]

big scam here in florida is the ductwork "cleaning".

I think that is a scam in most states. Lots of duct cleaning ads when we lived in Ohio.

 

[T_R_Oglodyte]

If duct corrosion is that much of an issue, I think there would be firms that could run a camera through the ducts to do a visual inspection of duct condition.

 

[davidvel]

My first response was it was a scam, but several homeowners I know responded that they had to replace because the ducts deteriorated and leaked.

If all of those homeowners went into their attics or used a remote camera to confirm this, then what they say would have meaning. Otherwise... I have worked in construction defect litigation for decades and never heard of such a thing across the board based on age.

 

[DrQ]

We have been having issues with an overflowing condensation line on the AC. The air handler was replaced about 10 years ago when we changed from an R22 to R410A.

I have cleaned the condenser drain several times over the years, but this time it seems the clog is in the standpipe which I suspect drains into the sewer system as there is a valve that is plumbed into the water supply which I suspect injects water into the line to keep the P-trap from drying out. This is the first time in 35 years that I have had a problem with this part of the system.

It several tries, but I was finally able to redirect the flow to a bucket to stop flooding the carpet in the hallway. I HATE squish when I walk to the bedroom.

I'm ordering a sink auger to see if I can clear the clog before throwing in the towel and calling a plumber.

 

[TUGBrian]

try to suck it out from the outside with a wet/dry shopvac?

 

[DrQ]

try to suck it out from the outside with a wet/dry shopvac?

Going to try the opposite direction after the auger:

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[TUGBrian]

hvac techs use these alot, however it would really suck to crack the pvc line using air pressure!

ive had great luck using the shop vac method, just make sure you are using a wet/dry vac because what comes out is nasty!

 

[DrQ]

hvac techs use these alot, however it would really suck to crack the pvc line using air pressure!

ive had great luck using the shop vac method, just make sure you are using a wet/dry vac because what comes out is nasty!

I hear ya. I have a shop vac (wet/dry) but it does not produce enough head to suck water directly. It has to "slurp" by mixing water and air. (hold on to your crude comments) Also, the standpipe is 3" with a 3/8" copper pipe that sticks into it from the device I've previously mentioned. Even if the shop-vac could suck water directly, the opening is too small for the hose. The crevice tool is too short to reach the p-trap, which is in or under the slab.

The plan:

1. Use the auger to break up the clog (which is probably mold/mildew/sludge)
2. Use an enzyme cleaner for A/C systems to soften the sludge/slime
3. Use the compressed CO2 to blow the softened gunk down the line

 

[CalGalTraveler]

When we replaced our furnace the honest HVAC rep told me this is a scam used by a lot of HVAC sales people to get more money. The first HVAC salesperson quoted double what we paid - felt like a timeshare preso. Asking the actual HVAC installers not the salespeople often will yield a more honest response.

I have seen neighbors waste a lot of money.

 

[TUGBrian]

sounds like an excuse to buy a much more powerful shop vac to me

 

[PigsDad]

My first response was it was a scam, but several homeowners I know responded that they had to replace because the ducts deteriorated and leaked.

Sounds like there is a very persuasive sales person in the area. I have never heard of any of my FL neighbors having to replace their ductwork. Seems like a scam to me.

Kurt

 

[rapmarks]

Sounds like there is a very persuasive sales person in the area. I have never heard of any of my FL neighbors having to replace their ductwork. Seems like a scam to me.

Kurt

Isn’t your subdivision fairly new?

 

[easyrider]

try to suck it out from the outside with a wet/dry shopvac?

I usually run an electrical fish tape through when this type of clog happens on a rental or friends and family home. It's only happened a few times. It's never happened to our HVAC system.

Bill

 

[PigsDad]

Isn’t your subdivision fairly new?

Our place is over 20 years old.

Kurt

 

[TheTimeTraveler]

Mini Splits are always a good alternative option to consider.. I put them in my Florida place in 2022 and it was the best move I could have made. No issues ever with duct work, and the air distribution is excellent with a high degree of energy efficiency in the process.

I actually purchased the splits via Costco and they had an A/C Contractor do the installation.....












.

 

[Ken555]

Interesting never heard of this but apparently in Florida it is common to have to replace the ductwork after 15 or 20 years
I do not recall this ever happening up a north.
I think about mine up north; it is between two finished floors.but in Florida, it is in a pretty small attic space.
Has anyone had their ductwork replaced?

Not in Florida, but we removed ductwork not long ago due to the fire contaminants and that it couldn't be cleaned, so deciding on the new install now. We are considering changing it to create two zones with separate hvac units to make it more efficient. If you need to change your ductwork, consider that as well if needed, since this is a good opportunity to make fundamental changes in how its implemented.

 

[TUGBrian]

side note on this topic as mini splits came up... if your situation allows it check out the inverter style "U-shaped" window ac units. Got one for moms house and its amazing! window is only open maybe 5 inches? unit slides down over the sill, no need for a mount or cantilever support! cant believe someone didnt come up with these sooner! 10k btu on 110volts and whisper quiet for under 350 bucks delivered on amazon!

hope it helps someone else that might have a hot room or difficulty with their hvac keeping up!

 

[DrQ]

side note on this topic as mini splits came up... if your situation allows it check out the inverter style "U-shaped" window ac units.

You can also buy units which are standalone and only the vent (4" hose) goes out the window.