AC short cycling

AC short cycling in Oviedo, Florida

Short cycling - the system starting, running a few minutes and stopping, over and over - is either a safety cutting it off or a system that is too big for the house. In Oviedo oversizing is the chronic cause, which is exactly why the City requires an ACCA Manual J-2016 load calculation on every changeout permit.

Diagnosis

What is most likely wrong

Likely causes, ordered by how often they turn out to be the answer
#	Cause	How common	What it looks like
1	Oversized equipment	Very common	Satisfies the thermostat in minutes, house feels cold and clammy, runs like this from the day it was installed.
2	Frozen coil or blocked filter	Very common	Cycles get shorter over days as airflow drops.
3	Low refrigerant tripping the low-pressure switch	Common	Runs, cuts out, restarts after a delay.
4	Failing run capacitor	Common	Compressor starts hard, then trips its overload.
5	Thermostat placement or a loose thermostat wire	Common	Stat in a hallway near a supply register, or in sun.
6	Condenser coil blocked, high-pressure cut-out	Less common	Cuts out on the hottest afternoons only.
7	Control board or relay fault	Less common	Random, no pattern.

Before you call

What you can safely check yourself

Time it: a healthy system in July runs 15 minutes or more per cycle. Under five is short cycling.
Filter, and any ice on the copper at the air handler.
Is the thermostat in direct sun, over a lamp, or in the path of a supply register?
Does it feel cold but damp? That is the oversizing signature, and it has probably always done this.
Look at the condenser coil for oak litter; a blocked coil trips the high-pressure cut-out on the hottest afternoons.

Where the licensed line is

Refrigerant, capacitors and the inside of an electrical panel are not homeowner jobs. A run capacitor holds a lethal voltage after the disconnect is pulled. Refrigerant handling requires EPA Section 608 certification. And in Florida the work itself is regulated: an air conditioning contractor licensed under Chapter 489 may replace, disconnect and reconnect the power wiring at the dedicated disconnect, and repair or replace disconnects, breakers and fuses on dedicated HVAC circuits — s. 489.105(3). Verify any Florida contractor’s licence, including ours, at DBPR Verify a Licensee.

In Oviedo

Why this happens in this housing stock

Oversizing is chronic in Oviedo for a specific reason: the rule-of-thumb sizing that put a four-ton unit on a 1,500 sq ft Alafaya Woods house in 1986 has been matched like-for-like at every changeout since. In a hot-humid Zone 2A climate the dominant load is latent, and a system that satisfies the thermostat in six minutes never runs long enough to pull the water out of the air. Cold and clammy is the defect, not a comfort setting.

Which is why this city’s permit guideline is the fix. The City of Oviedo requires the equipment sizing calculation — ACCA Manual J-2016 — uploaded with every changeout application, and the model numbers of what is going in. A contractor who plans to “put back the same tonnage” cannot complete that application. If you have a short-cycling system, ask to see the Manual J that was filed for it. What it should contain. Remington Park’s larger late-80s houses on a single oversized system are the textbook case.

Housing stock: Seminole County Property Appraiser CAMA extract, Parcels.csv dated 5 September 2026. Median build year 1995; 25.0% of parcels built 1970–89; 39.4% with a pool.

Cost

What the fix typically costs

Researched repair ranges for this symptom, 2026
Job	Researched range	Notes
Diagnostic visit, national	$75–$150	This Old House 2026. A competing Oviedo contractor publishes $89, waived with a completed repair.
Capacitor replacement	$150–$400	Angi puts the average at about $250 fitted.
Refrigerant leak repair	$200–$1,500+	Finding the leak is most of the cost; weigh it against the R-410A phase-down.
Thermostat repair or replacement	$100–$500	From a $20 mechanical stat to a communicating control matched to the equipment.
Right-sized changeout, home of about 2,000 sq ft	$5,000–$8,000	Florida cost guide. Plus the City permit at $50 + $6 per $1,000 above $2,000, with the Manual J attached.

Read this before you use any number on this page. Every figure here is a researched third-party market range with its source and capture date named beside it. None of them are a contractor’s price and none of them are a quote. They are here so you can sanity-check a quote you have already been given.

Not getting anywhere?

Tell us the symptom, the build year of the house and roughly how old the equipment is. That usually narrows it to two candidates before anyone drives out.

Call (321) 415-3018 Send the address and build year

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