Coates Electric Pool Heater, 57kw 208V Three Phase, Salt Water Application

The Coates 57kW 208V Three-Phase Electric Pool & Spa Heater for Salt Water Applications (Model 32057CES / 32057CPHS — featuring the "S" saltwater/corrosion-resistant package) is the highest-capacity standard unit in Coates' 208V three-phase commercial portfolio. It is engineered for large municipal therapy pools, commercial swim schools, resort aquatic complexes, and athletic recovery facilities operating with electrolytic salt chlorine generation systems (typically 2,500 to 4,500+ ppm TDS/NaCl) on a 208V 3-phase/4-wire distribution network.

Operating 57kW across 208V 3-phase draws 158.2 Amps per phase (compared to 237.5 Amps on single-phase 240V). The factory saltwater configuration provides upgraded metallurgy and protective tank barrier coatings to withstand aggressive saline electrolytes, preventing chloride pitting and stress corrosion cracking.

Electrical & Heating Performance

• Model Designation: Coates 32057CES / 32057CPHS series (320 designates 3-Phase 208V; suffix designates Saltwater/Titanium package).

• 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: 208V AC, Three-Phase (3Ø), 3-pole / 3-wire plus ground (or 4-wire Wye), 60 Hz.

• Full Load Amperage (FLA): 158.2 Amps

  $$\text{FLA} = \frac{57,000\text{ W}}{208\text{ V} \times \sqrt{3}} = \frac{57,000}{360.26} \approx 158.22\text{ A} \rightarrow 158.2\text{ A}$$

• Overcurrent Protection (Breaker Sizing): Requires a dedicated 3-pole 200-Amp circuit breaker conforming to NEC/CEC 125% continuous-duty loading standards ($158.22\text{ A} \times 1.25 = 197.77\text{ A}$ minimum branch rating, standardizing on a 200A 3-pole breaker).

• Conductor Sizing: Minimum #3/0 AWG or #4/0 AWG THHN/THWN copper conductor (rated 75°C/90°C terminals, adjusted for ambient derating and raceway distance).

Salt Water Construction & Metallurgy Upgrades

• Titanium / Incoloy 825 Sheathed Elements: Immersion elements are upgraded from standard alloys to Titanium or high-molybdenum/nickel Incoloy 825 sheathing to resist chloride-induced stress corrosion cracking (SCC), scale accumulation, and localized pitting from dissolved sodium chloride and electrolytic chlorination.

• Passivated / Barrier-Coated Pressure Vessel: Extended cylindrical pressure chamber fabricated from heavy-gauge 316L stainless steel or carbon steel lined with a specialized baked phenolic epoxy/fluoropolymer protective barrier, isolating the tank substrate from saline electrolytic degradation.

• Sacrificial Cathodic Protection: Equipped with an accessible sacrificial zinc or magnesium anode plug port to absorb galvanic action and mitigate stray current erosion in the salt plumbing loop.

• Corrosion-Inhibited Cabinet: Heavy-gauge NEMA 1 industrial painted enclosure finished with an anti-corrosion powder coating to prevent cabinet degradation in high-humidity, salt-vapor mechanical rooms.

Construction & Safety Architecture

• Cabinet & Enclosure: NEMA 1 industrial painted steel cabinet with a removable front panel for terminal inspections, multiple staged heavy-duty 3-pole magnetic contactor servicing, and field wire terminations.

• 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 (adapted via Schedule 80 CPVC unions into 2", 2-1/2", or 3" headers).

• Equipment Sequencing in Salt Systems: Must always be installed upstream of the electrolytic chlorine generator cell (separated by an inline corrosion-resistant check valve) to prevent hyper-concentrated chlorine gas or acidic pockets from pooling inside the heater vessel during pump shutdowns.

• 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 across multi-element arrays.

  • 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 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.)