AC not turning on

AC not turning on in Oviedo, Florida

A system that is completely dead is almost always a power or safety interlock problem: a tripped breaker, a pulled disconnect, a condensate float switch that has cut the low-voltage circuit, or a thermostat with flat batteries. In Oviedo the float switch is the one people miss, because a blocked drain line looks like an electrical fault.

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	Tripped breaker or pulled disconnect	Very common	Nothing runs inside or out. Check the panel and the box by the condenser.
2	Condensate float switch tripped	Very common	Everything dead, no lights, a full secondary pan or a wet stain below the air handler.
3	Thermostat batteries or settings	Very common	Blank screen, or a schedule or hold that is not what you think.
4	Blown 3A or 5A low-voltage fuse on the control board	Common	Thermostat lit, nothing responds. Usually a shorted thermostat wire or a failed contactor coil behind it.
5	Failed contactor or transformer	Common	Indoor blower runs, outdoor unit never starts, or nothing at all.
6	Blower door safety switch	Less common	Air handler panel not fully closed after a filter change.
7	Failed control board	Less common	Intermittent operation before going dead.

Before you call

What you can safely check yourself

Thermostat: screen on, set to cool, batteries fresh, no hold or schedule overriding you.
Both breakers, reset once. A breaker that will not stay reset is a stop sign, not a challenge.
The outdoor disconnect pull-out, fully seated.
The secondary drain pan under the air handler and the ceiling below it: water means the float switch has tripped and the drain line is the fault.
The air handler door: it must be fully latched for the safety switch to close.

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

The float switch is the Oviedo cause because the drain line is the Oviedo failure. Nine months of condensing in a Climate Zone 2A house, 39.4% of them with a screened pool deck adding moisture, plus the organic load from oak canopy, grows sludge in a condensate line faster than anywhere without trees. When the line blocks, the switch cuts the low-voltage circuit and the whole system goes dark with no fault code — which is why a $150 drain call gets misdiagnosed as a $500 control board.

The electrical causes cluster in the older stock. 25.0% of Oviedo was built 1970–89; Alafaya Woods panels and disconnects are forty years old and have been through two or three changeouts, each one reusing the same breaker and the same whip. A contactor with pitted contacts or a transformer at the end of its life is normal there. If the fault is at the disconnect or the dedicated breaker, that is inside the scope a Chapter 489 air-conditioning contractor may work on — s. 489.105(3).

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.
Drain line clearing	$80–$250	The routine Central Florida call.
Contactor or relay	$100–$450	A wear item.
Thermostat repair or replacement	$100–$500	From a $20 mechanical stat to a communicating control matched to the equipment.
Capacitor replacement	$150–$400	Angi puts the average at about $250 fitted.

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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