Air to Water Heat Pump -EVI DC Inverter 20 tons Split - Model HSS250V3LS - R32 Refrigerant - Operating Temperatures -30⁰C to +45⁰C

Introduction

Air to Water Heat Pump is a closed loop thermal device that draws heat from one place (called heat source) and rejects the drawn heat to another place (called heat sink). Unlike conventional air to air heat pump, where generated thermal energy is used to cool/heat air fluid, Air to Water Heat Pumps use generated thermal energy to  cool/heat water or water/glycol fluid mixture. Our Split Series Air to Water Heat Pumps can work at outdoor temperatures ranging between -30⁰C and +45⁰C.

Specifications:

• Model Number: HSS250V3LS (Copper Heat Exchanger) - HSS250V3LS-T (Titanium Heat Exchanger).
• Nominal Cooling Capacity: 20 Tons (250 000 Btu/hr).
• Outdoor Operating Temperature range: -30⁰C (-20.2⁰F) to +45⁰C (113⁰F)
• Power Supply: 380-415V / 3 Ph / 60Hz.
• Noise Level: 67 dBA.
• Full Load Amp (FLA): 72 A.
• MCA / MOP: 115 / 207 A.
• Nominal Heat Transfer Fluid Flow (US GPM): 57.
• Water Friction Loss at Nominal Flow (ft W.G.): 12.71.
• Water Inlet/Outlet Diameter: 3" Flanged.
• Chilled Water Supply Temperature: Nominal 7⁰C (44.6⁰F), Minimum 5⁰C (41⁰F). Maximum 12⁰C (53.6⁰F).
• Hot Water Supply Temperature: Minimum 35⁰C (95⁰F), Maximum 60⁰C (140⁰F).
• Heat Pump is equipped with outdoor temperature reset feature.
• Controller uses Modbus Protocol (BMS interface cards are available upon request).
• DC Inverter Panasonic Compressor with Enhanced Vapor Injection.
• Uses R32 Refrigerant.
• Certification: CSA C22.2 No. 236-15 and UL 1995:2015 R8.18 (In Process Certification)

Typical ATW HP Installation

Air to Water Heat Pump can be used for various applications that require a Hot or Chilled Heat Transfer fluid. The most common applications are Hydronic Space Heating and Cooling, Domestic Hot Water Pre-Heating, SPA or Pool Heating (when used with Titanium Heat Exchangers) and Process Heating.

The most common typical installation is with 2 buffer tanks, a three way valve and a circulation pump dedicated for the air to water heat pump:

This configuration is the recommended one for optimizing the performance of the heat pump. In the heating season, it allows the DHW heating tank and the space heating tank to be maintained each at a separate temperature (lower temperature for the space heating tank). This reduces the power consumption of the heat pump since its power draw decreases when its hot water supply temperature decreases. In the summer season, the above installation with 2 tanks allows the heat pump to produce chilled water for space cooling (Tank T-02) and DHW hot water (Tank T-01). The priority between the two tanks can be selected in the menu of the HP controller.

In projects where Operating Space Heating temperature is close the DHW heating one and/or no cooling in the project, one buffer tank can be used:

In the above configuration, a buffer tank with indirect coil is needed. The indirect coil will be used to preheat DHW and the tank will be used for space heating and/or cooling. When Heat pump is in cooling mode, the indirect coil used to preheat DHW is bypassed by an ON/OFF 3 way valve (managed by the controller of the HP).

Control and Wiring Interface

Controller of the Heat Pump is designed to manage everything between the HP and the two tanks. This includes the 3 way valves (Floating type for 2 tanks configuration - 2 Pipe System and ON/OFF type for single tank configuration or 2 tanks configuration with a 4 pipe system), Circulation Pump, DHW heating backup heat, Space heating Backup Heat and the temperature of the two tanks.

Heat Pump has an outdoor temperature sensor and it can be programmed to switch between cooling and heating automatically based on outdoor temperature. It has also the possibility to be managed by a third party controller: It can be turned ON/OFF via port 7-8, Switched to Cooling via port 7-9 and switched to Heating via port 7-10.