Pool heater not working in North Port? Start here.

First: which kind of heater do you have?

It changes the whole diagnosis. In North Port and the rest of Sarasota County, the two common types are:

• Heat pump (electric) — a large box with a fan on top, like an AC condenser. Most common on Florida residential pools because our climate suits it. Heats slowly and cheaply.
• Gas (natural gas or propane) — smaller, with a flue/exhaust on top and a gas line running to it. Heats fast, costs more to run. Common on spas and pools people want hot on demand.

The 5-minute checks (do these before calling anyone)

1. Is the pump running and is flow strong? Nearly every heater has a flow or pressure switch that refuses to fire if water isn't moving fast enough. A clogged filter or cartridge is the #1 cause of "heater suddenly stopped." Backwash or clean the filter and try again.
2. Is the thermostat actually calling for heat? Set point above current water temp, and the system in a run cycle (not stuck in "off" on the timer or automation panel).
3. Power and fuel: Heat pump — check the dedicated breaker. Gas — check the gas valve is fully open and, if propane, that the tank isn't empty.
4. Look for an error code on the display and write it down (see below).

If all four are good and it still won't heat, the table below points you at the likely fault.

What the symptom usually means

What you see	Most likely cause	DIY or pro?
No display, no response	Tripped breaker, blown fuse on control board, or no power	Reset breaker once; if it trips again, pro
Display on, won't fire, flashes flow/pressure fault	Dirty filter, closed valve, weak pump, or failed flow switch	Clean filter (DIY); switch is a pro fix
Gas heater clicks/sparks but won't light	Gas supply, dirty flame sensor, weak igniter, or insect nest in burner tray	Pro — involves gas
Lights then shuts off after seconds	Flame sensor not proving flame, or high-limit/overheat trip from low flow	Pro
Heat pump runs constantly, water stays cold	Low refrigerant (leak), iced coil, or reversing-valve fault	Pro — sealed system
Rusty water stains, green/white crust at the heat exchanger	Corroded or leaking heat exchanger	Pro — often means replace

Common error codes, decoded

Codes vary by brand (Pentair, Hayward, Raypak, Jandy are what you'll see most here), but the families are consistent:

• "LO" / flow fault / "no flow" — not enough water moving. Filter, valve, or flow switch. Start with the filter.
• "IF" / ignition fault / "no ignition" (gas) — tried to light and failed. Gas supply, igniter, flame sensor, or a blocked burner.
• "HS" / high-limit / "stack flue" — overheat or exhaust sensor trip, frequently caused by low flow cooking the heat exchanger. Stop running it and get it checked — this one can cause real damage.
• "E05"/"E06" or sensor faults — a water or air temperature sensor is out of range or failed. Usually an inexpensive part.

Why heaters fail faster in Southwest Florida

This isn't generic filler — it changes what fails. Three local realities:

• Salt-chlorinated pools. Very common here. If the heater was plumbed without the manufacturer's required clearance or with the wrong (non-cupronickel) heat exchanger, the salt cell's byproducts corrode it years early.
• Long idle stretches. Many pools run unheated April through November. Idle gas burners are where insects nest — mud daubers blocking the burner tray is a classic "first cold morning, won't light" call.
• Coastal air. Closer to the Gulf, salt air pits heat-pump coils and gas cabinet hardware. It's why a 10-year-old unit inland can look better than a 6-year-old unit near the water.

Repair vs. replace: real numbers (2026, SW Florida)

Ballpark ranges so you're not negotiating blind. Your quote depends on brand, access, and gas/electrical work:

• Diagnostic / service call: typically $90–$175, often credited toward the repair.
• Igniter, flame sensor, or temp sensor: roughly $150–$400 installed.
• Flow switch / control board: roughly $250–$700.
• Heat exchanger replacement: often $700–$1,500+ — at this point, weigh against a new unit.
• New heat pump installed: roughly $4,000–$6,500.
• New gas heater installed: roughly $3,500–$6,000, more if gas line work is needed.

The honest decision rule: repair if the unit is under ~8 years old and the heat exchanger is sound; replace once the heat exchanger is the failure or a single repair tops half a new unit's price.