Water-to-water heat pump THERMIA CALIBRA E 8 DUO (WW) – 2–8 kW, up to 65 °C, without DHW tank

Product detailed description

THERMIA CALIBRA E 8 DUO WW (code IHP203646WW) is an inverter-controlled heat pump in the water/water version. The source water from the well transfers heat to the non-freezing fluid circuit in the supplied plate heat exchanger and is returned to the recharge well. The DUO model has a lower cabinet (height 1450 mm) without a storage tank – hot water is prepared in a separate heater, for example, a freestanding stainless steel MBH TWS. The CALIBRA E series is suitable for buildings with heat loss up to 24 kW.

Main features

• inverter-controlled Copeland scroll compressor and variable-speed circulation pumps – the output continuously adapts to the house's needs in the range of 2–8 kW
• water outlet temperature up to 65 °C, suitable for underfloor heating and radiators
• refrigerant R452B with GWP 698 (charge 0.9 kg), stainless steel plate heat exchangers
• COP 4.6 at B0/W35 (EN 14511), energy class A+++ for 35 and 55 °C
• the supplied plate heat exchanger requires a source water flow of 0.58 l/s at ΔT 3 K, its pressure loss is 40 kPa
• control system GENESIS with a color touch display, built-in web server for Thermia Online, Modbus for building automation and Smart Grid function for photovoltaics
• anti-vibration flexible pipe built into the cabinet – external flexible hoses are not required

System expansion

The expansion card EM3 is already included in the WW version, so the heat pump can control a mixed circuit, an external auxiliary heat source, an activated buffer tank, and pool heating. The submersible pump for the well is ordered separately; for efficient operation, the manufacturer recommends controlling it with a frequency inverter.

Design and installation

The performance is designed in the calculation program Thermia HPC. The heat pump is placed in a frost-free room on a solid base, ideally a concrete floor, and not in a corner. The non-freezing fluid circuit is filled with a water and ethanol mixture with a freezing point of -17 ± 2 °C, the return heating circuit requires a magnetic dirt separator with a filter, and the system must contain at least 14 l of water per kW of minimum output. The connecting kit IVAR.TER-PS (IHP08645678) is ordered separately. Installation and commissioning are carried out by a professional company, electrical installation by an electrician, and work on the refrigeration circuit by a technician qualified in refrigeration technology.

Technical parameters

Frequently asked questions

For which type of house is the CALIBRA E 8 DUO heat pump suitable?
The model operates in the range of 2–8 kW with water temperatures up to 65 °C, making it suitable for underfloor heating and radiators in new builds and renovations. The exact output is determined by a calculation in the Thermia HPC program based on the house's heat loss.

What is included in the delivery?
In addition to the safety valves 9 and 3 bar, the external sensor, expansion tank, and charging equipment for the non-freezing fluid circuit, the WW version also includes a built-in heat exchanger, flow sensor, and EM3 card. The connecting kit IVAR.TER-PS (IHP08645678) and hot water storage tank are ordered separately.

Is the submersible pump for the well included in the delivery?
No, the submersible pump for the source water is ordered separately. This model requires a source water flow of 0.58 l/s at ΔT 3 K.

Can the heat pump be controlled remotely?
Yes, the built-in web server allows control and monitoring via Thermia Online from a phone, tablet, or computer. The Smart Grid function also enables cooperation with photovoltaics.