Coates Electric Pool Heater, 18kw 240V Single Phase

The Coates 18kW 240V Single-Phase Electric Pool & Spa Heater (Model 12418CE / 12418CPH) is a commercial-grade, inline immersion electric heater designed for high-capacity commercial spas, hydrotherapy tanks, aquatic training tanks, and small commercial pools requiring rapid recovery rates without natural gas or propane infrastructure.

Electrical & Heating Performance

• Model Designation: Coates 12418CE / 12418CPH series.

• Heating Capacity: 18 kW (18,000 Watts).

• Thermal Output: 61,418 BTU/hr ($18\text{ kW} \times 3,412.142\text{ BTU/kWh}$).

• Operating Voltage: 240V AC, Single-Phase (1Ø), 60 Hz.

• Full Load Amperage (FLA): 75.0 Amps ($18,000\text{ W} / 240\text{ V} = 75.0\text{ A}$).

• Overcurrent Protection (Breaker Sizing): Requires a 100-Amp dedicated double-pole circuit breaker to satisfy NEC continuous-duty loading ($75.0\text{ A} \times 1.25 = 93.75\text{ A}$ minimum branch rating).

• Conductor Sizing: Minimum #1 AWG or #1/0 AWG THHN/THWN copper conductor (rated 75°C/90°C, verified against terminal lug temperature ratings, conduit fill, and run distance).

Construction & Safety Architecture

• Pressure Vessel: Welded heavy-gauge steel/stainless steel cylindrical pressure chamber treated internally to withstand continuous commercial water velocity and aggressive pool sanitizer chemistry.

• Heating Elements: Heavy-duty screw-plug immersion elements featuring corrosion-resistant Incoloy 800/825 sheathing to prevent pitting, scale accumulation, and chemical erosion.

• Cabinet & Enclosure: NEMA 1 industrial-grade painted steel enclosure with front-access service panel for terminal torque inspection, wiring, and element service.

• Integrated Safety Controls:

  • Dual-dial adjustable thermostatic controller calibrated up to 104°F (40°C) for commercial spa compliance.

  • Manual-reset High-Limit safety switch set to cut off power at 122°F (50°C).

  • Flow-interlock switch preventing heating element energization in zero-flow or deadhead pump conditions.

Hydraulic & Plumbing Specifications

• Plumbing Connections: Standard 1-1/2" NPT female inlet and outlet ports.

• Water Flow Range:

  • Minimum Flow Rate: 15 to 20 GPM (approx. 57 to 76 LPM) required to trip the internal safety flow interlock.

  • Maximum Flow Rate: 60 to 70 GPM (approx. 227 to 265 LPM); systems exceeding this volume require an external bypass manifold.

• Maximum Working Pressure: 60 PSI (approx. 4.14 bar).

Dimensions, Net Weight & Shipping Weight

• Unit Dimensions: Approximately 19.5" L × 10.0" W × 14.5" H (approx. 49.5 cm × 25.4 cm × 36.8 cm).

• Net Unit Weight: Approximately 50 to 56 lbs (approx. 22.7 to 25.4 kg).

• Packaged Shipping Dimensions: Approximately 22" L × 13" W × 17" H.

• Packaged Shipping Weight: Approximately 62 to 70 lbs (approx. 28.1 to 31.8 kg) in reinforced corrugated packaging with dense protective foam inserts.

Estimated Temperature Rise Rates

(Calculation: $\text{Rise (°F/hr)} = \frac{61,418\text{ BTU/hr}}{\text{Gallons} \times 8.34\text{ lbs/gal}}$, baseline heat-up rate assuming covered vessel without ambient losses.)