Note: 1.This machine can be used with Single-phase 220V or dual-phase 110V(110V: Connect to dual-phase 110V, one L1 and one L2 220V: one connected to L, one connected to N)2.please confrim the wire referring to the power of the unit,here are the curren18KW/220V =82A,about 82ASpecifications:Liner material: stainless steelVoltage: 110/220V (Transformer required)Power: 18KWPhase: single phaseConnection size: 40 mm (1.57 ")Machine size: 49 x 10 x 38 cm / L x W x H.Suitable for: hot tub & swimming pool equipmentIntelligent temperature control, stable performance, safe and reliableAutomatic constant temperature, can be set according to the required water temperature.The maximum set temperature is approx. 55 ° C.Safe and reliable, mechanical pressure switch.When the pressure is below the set value, the power supply is automatically switched off.Do not heat sea water or salt water.The thermostat must work with a water pump with an appropriate capacity.(If the pump and thermostat do not match, the flow rate is too low, the heating pipe is dry and can easily be damaged.)18KW-36KW heaters must operate with a pump with a water flow of at least 353 ft³ / hour (10m³/hour).The 18KW thermostat is suitable for a pool with ≤ 424 ft³ / 12m³Operating procedure: first turn on the water pump and then the thermostat.Shutdown:First turn off the thermostat, wait a while (10 seconds to 1 minute depending on the performance of the thermostat) and then turn off the pump.Reliable leak protection devices must be installed and commissioned by the responsible electrician. Monthly maintenance and inspection.The additional heating effect of the thermostat is better. Direct heating requires the us