Comfort
Humidity and indoor air quality in Longwood, FL
A Longwood house that reads 75°F and still feels clammy has a moisture problem, not a temperature problem. The usual causes are an oversized system that short-cycles, leaking duct in a 130°F attic, and restricted return air in a 1970s floor plan with one central grille.
Why Florida is different
Latent load is the job, not a side effect
Central Florida runs roughly 51.5 inches of rain a year and about 3,452 cooling degree days at the nearest long-record station. The DOE puts Florida in the hot-humid Southeast region on exactly that basis — cooling hours, and the humidity during them. Removing moisture is half of what the system is for, and it only happens while the equipment is actually running and the coil is cold.
- Short cycling from an oversized system. It hits the set point, stops, and never dehumidifies. Why sizing causes this.
- Leaking or disconnected duct. Return duct leaking in an attic pulls in hot, humid air and delivers it to the coil; supply leaks give away capacity. Duct work, priced.
- Restricted return air. One central return grille was adequate for a 1970s blower. It starves a modern one, which reduces airflow across the coil and, at the extreme, freezes it.
- A dirty filter or fouled coil. The cheapest of these to fix and the most common to find. Filter cadence here.
What the canopy does
Pollen, leaf dust, and no salt air
The other half of indoor air quality here is what gets into the system. Longwood sits under mature oak and pine, and the pollen load in spring and the leaf dust in autumn both end up at the filter and on the outdoor coil. Inland Seminole County has one advantage over a beachside job: no direct salt-air corrosion on the condenser. The stressors here are heat hours, humidity and canopy debris.
Practical order of attack, cheapest first: check and change the filter; clear the condenser of leaf litter and restore clearance around the cabinet; have the condensate drain cleared, particularly with an attic air handler; then test the duct. Only after those does equipment replacement or a dedicated dehumidifier become the right conversation.
One Longwood-specific permission: the City exempts owner-occupied single-family homes from tree removal permitting, so cutting back the crown that shades and fouls your condenser needs no City permit. The rule, in the City's own words.
Sources
- NOAA 1991–2020 climate normals, Orlando station. https://www.ncei.noaa.gov/products/land-based-station/us-climate-normals
- U.S. DOE, 2023 Central Air Conditioner Standards FAQ. https://www1.eere.energy.gov/buildings/appliance_standards/pdfs/2023_CAC_Standards_FAQ_10-5-2022_Final.pdf
- Seminole County Property Appraiser CAMA extract (Parcels.csv, dated 5 September 2026), tax district L1 — Longwood; improved residential parcels, DOR codes 01 and 04. https://www.scpafl.org/
- City of Longwood FAQ: “Do I need a permit to remove a tree?”. https://longwoodfl.org/FAQ.aspx?QID=163
- Duke Energy news release, 9 June 2025 — expanded Florida home improvement rebates. https://news.duke-energy.com/releases/duke-energy-expands-home-improvement-rebate-program-to-help-florida-customers-save-energy-and-money-this-summer
Figures are dated. Permit fees, rebate amounts and code cycles change — re-check the primary source before you rely on a number here.
Clammy at 75 degrees is a diagnosis, not a preference
It tells us where to look. Describe it that way when you call and we will start in the right place.