Coates Electric Pool Heater, 57kw 600V Three Phase

The Coates 57kW 600V Three-Phase Electric Pool & Spa Heater (Model 36057CE / 36057CPH) is the highest-capacity standard unit in the Coates 600V lineup, engineered for large municipal therapy pools, commercial swim schools, resort aquatic complexes, and institutional athletic training tanks operating on a standard 600V 3-phase distribution network (predominant across Canadian commercial and industrial facilities).

Operating 57kW on a 600V 3-phase supply draws merely 54.8 Amps, delivering close to 200,000 BTU/hr of thermal energy on a single 3-pole 70A or 80A 600V circuit with standard #4 AWG copper wiring—avoiding the massive 200A+ services or split sub-feeds required by lower-voltage installations.

Electrical & Heating Performance

• Model Designation: Coates 36057CE / 36057CPH series (360 designates 3-Phase, 600V).

• Heating Capacity: 57 kW (57,000 Watts).

• Thermal Output: 194,492 BTU/hr ($57\text{ kW} \times 3,412.142\text{ BTU/kWh}$).

• Operating Voltage: 600V AC, Three-Phase (3Ø), 3-pole / 3-wire plus ground (or 4-wire Wye), 60 Hz.

• Full Load Amperage (FLA): 54.8 Amps

  $$\text{FLA} = \frac{57,000\text{ W}}{600\text{ V} \times \sqrt{3}} = \frac{57,000}{1,039.23} \approx 54.85\text{ A}$$

• Overcurrent Protection (Breaker Sizing): Requires a dedicated 3-pole 70-Amp or 80-Amp circuit breaker (600V-rated) conforming to continuous-duty branch loading requirements ($54.85\text{ A} \times 1.25 = 68.56\text{ A}$ minimum branch rating, standardizing on a 70A or 80A 600V 3-pole breaker).

• Conductor Sizing: Minimum #4 AWG copper conductor (rated 600V, 75°C/90°C THHN/THWN/RW90, adjusted for ambient derating and raceway fill).

Construction & Safety Architecture

• Pressure Vessel: Heavy-gauge, welded cylindrical steel/stainless steel pressure vessel treated internally with a baked corrosion-resistant protective coating to endure continuous commercial water velocity and aggressive sanitizing chemicals.

• Heating Elements: Screw-plug commercial immersion elements rated for 600V operation, sheathed in premium Incoloy 800/825 or Titanium alloy to resist pitting, scale accumulation, and high thermal stress.

• Cabinet & Enclosure: NEMA 1 industrial painted heavy-gauge steel cabinet with a removable front access panel for terminal inspections, 600V-rated magnetic contactor servicing, and field wire terminations.

• Internal Control Circuit: Factory-installed step-down control transformer (600V primary to 120V/24V secondary) powering the thermostatic control circuit and safety interlocks.

• Integrated Safety Controls:

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

  • Manual-reset High-Limit safety cutout set to de-energize the magnetic contactor control circuit at 122°F (50°C).

  • Pressure/flow-interlock switch preventing heating element contactors from pulling in during low-flow, pump loss, or deadhead conditions.

Hydraulic & Plumbing Specifications

• Plumbing Connections: Standard 1-1/2" NPT female inlet and outlet ports (typically adapted via Schedule 80 unions into 2", 2-1/2", or 3" CPVC headers).

• Flow Rate Parameters:

  • Minimum Flow Rate: 30 to 35 GPM (approx. 114 to 132 LPM) required to trip the safety flow switch and prevent localized thermal cavitation.

  • Maximum Flow Rate: 60 to 70 GPM (approx. 227 to 265 LPM); filtration loops operating at higher GPM mandate an external plumbed bypass manifold.

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

Dimensions, Net Weight & Shipping Weight

• Unit Dimensions: Approximately 24.0" L × 12.0" W × 16.5" H (approx. 61.0 cm × 30.5 cm × 41.9 cm).

• Net Unit Weight: Approximately 90 to 98 lbs (approx. 40.8 to 44.5 kg).

• Packaged Shipping Dimensions: Approximately 26" L × 15" W × 19" H.

• Packaged Shipping Weight: Approximately 105 to 118 lbs (approx. 47.6 to 53.5 kg) in heavy-duty reinforced corrugated carton packaging with dense molded foam protection.

Estimated Temperature Rise Rates

(Calculation: $\text{Rise (°F/hr)} = \frac{194,492\text{ BTU/hr}}{\text{Gallons} \times 8.34\text{ lbs/gal}}$, baseline heat-up rate assuming covered vessel without ambient radiation losses.)