Heat Pump vs Gas — FL Comparison
- Gas Heater (NG or LP): Fastest heat (2–4 hrs), works below 55F, efficiency 82–95% (condensing). Best for infrequent heating, spas, quick warmup. NG ~$0.80–1.20/therm; LP ~$2.50–3.50/gal. Monthly FL cost $80–$250 (NG) or $200–$600 (LP).
- Heat Pump: Lowest operating cost; FL's warm climate ideal. COP 4–6 means $1 electricity = $4–6 heat. Best for maintaining temperature daily; works above 55F. Monthly FL cost $30–$100. Slower: 8–24 hrs full heatup.
- Hybrid System (FL Recommended): Heat pump primary (low cost), gas backup for cold nights or rapid heatup. Most cost-effective for year-round use. Payback vs gas-only: 3–5 years.
NFPA 54 Pool Heater Pipe Sizing Quick Reference
Natural gas, low pressure (7" WC), Schedule 40 black iron pipe:
| Pipe Size | 50 ft run | 75 ft run | 100 ft run |
|---|---|---|---|
| 1/2" | 72,000 | 59,000 | 50,000 |
| 3/4" | 151,000 | 124,000 | 107,000 |
| 1" | 285,000 | 234,000 | 202,000 |
| 1-1/4" | 542,000 | 444,000 | 384,000 |
| 1-1/2" | 822,000 | 673,000 | 583,000 |
LP gas: multiply BTU capacity by ~0.40. Size the line for total BTU demand including all connected appliances, not just the pool heater — undersized pipe = failed inspection.
Pool Gas Line Pre-Inspection Checklist
- Gas pipe is black iron or CSST (not galvanized or copper for NG)
- CSST bonded with #6 AWG copper within 6 ft of meter
- Sediment trap / drip leg installed at heater connection
- Manual shutoff valve within 6 ft of heater (accessible)
- Heater has 18" clearance from any combustible
- Pressure test performed (10 PSI air for 15 min — FL code)
- Heater is listed/labeled (AGA, CSA, or UL)
- FL pool plumbing permit applied for (separate from gas permit)
FL Pool Heater & Gas Code Requirements
Florida pools require two separate permits: a pool/equipment permit (FBC Chapter 34) AND a gas permit (FPC Section 406) when a gas heater is installed. Both require a licensed contractor. - Pool Equipment Permit (FBC Chapter 34): Any heater install/replacement. Licensed pool contractor (CPO) or plumbing contractor (CPC). Plans show heater location, gas stub-out, pad dimensions. - Gas Permit (FPC Section 406): Separate permit for any new gas line or heater connection. Licensed CPC with gas certification. Pressure test (10 PSI air, 15 min) before inspection. - NFPA 54 Pipe Sizing: All FL residential gas installs must comply; pipe must accommodate total BTU demand of all appliances. - CSST Bonding (FL Code 406.6): CSST bonded to grounding electrode with #6 AWG copper within 6 ft of meter (required since 2009). - Pool Electrical Bonding (NFPA 70/FBC): All metallic equipment including gas heater shell bonded to #8 AWG copper grid; pool water bonding via sacrificial electrode. Gas heater + pool = two separate bonding requirements. - Setback/Clearance: Gas heater 18" from combustibles, 36" service clearance. Heater outside pool barrier or continuous barrier. Screen enclosure: confirm combustion air per manufacturer. Coastal FL (within 1 mile of salt water): corrosion-resistant materials. - Propane (LP) Additional Rules: LP tank permit (NFPA 58); above-ground tank min 10 ft from pool equipment; underground min 10 ft from pool; LP regulator and second-stage regulator required; heater must be rated for LP (not interchangeable without conversion kit). - License: Licensed CPC with Section 1 gas license OR licensed pool contractor with gas endorsement. Miami-Dade, Broward, Palm Beach often require local license. Do NOT allow unlicensed "pool guys" to run gas lines.
FL County Pool Heater Notes
- Miami-Dade: Local MDBC license required; strict gas inspection; NOC for heater replacement.
- Broward: Pool + gas permits required even for heater-only replacement.
- Palm Beach: Coastal corrosion provisions; salt air heater ratings enforced.
- Hillsborough: Combined pool/gas permit available; 48-hr inspection scheduling.
- Orange/Osceola: Vacation rental pools — DBPR may inspect heater operation.
- Pinellas: Wind mitigation forms for equipment in coastal HVHZ zones.
- Collier/Monroe: HVHZ — heater must be anchored to pad.
FL Pool Heater Cost Guide
| Item | Cost |
|---|---|
| Gas heater (150K BTU) | $1,800–$3,200 installed |
| Gas heater (250K BTU) | $2,500–$4,500 installed |
| Heat pump (5-ton) | $2,800–$5,000 installed |
| Hybrid system | $4,500–$8,000 installed |
| New gas line (50 ft) | $600–$1,400 |
| FL pool heater permit | $100–$400 |
| FL gas permit | $75–$250 |
Pool heater BTU sizing note: FL average current water temp ~72F. Comfortable swimming 80–84F; spa 100–104F; therapy/seniors 86–92F. Heater sizing affected by pool surface area, desired temp, wind exposure (screened enclosure most common in FL), and pool cover use.