Thermia BW ATLAS 18 ground-source heat pump – 4–18 kW, 184 l DHW cylinder, flow up to 65 °C – SALE

Product detailed description

Thermia BW ATLAS 18 is a premium inverter brine-to-water heat pump in a compact cabinet. Besides the refrigerant circuit it houses the control unit, circulation pumps, a 3-way heating/DHW valve, an electric backup heater and a 184 l stainless steel hot water cylinder. The output varies steplessly within 4–18 kW and the flow temperature reaches up to 65 °C, so the unit suits both new builds and renovations; the ATLAS range is intended for buildings with a heat loss of up to 30 kW.

Hot water with HGW and TWS technology

The hot gas exchanger (HGW) heats domestic hot water simultaneously with space heating, and the TWS coil ensures fast heating and stable stratification in the cylinder. According to EN 16147, 344 l of water at 40 °C are available, and up to 545 l with full use of HGW. Thanks to the hot gas, the water in the cylinder can reach up to 95 °C, so a thermostatic mixing valve is fitted on the hot water outlet.

Specifications and equipment

• SCOP 6.15 at 35 °C and 4.55 at 55 °C (EN 14825, cold climate), COP 4.98 at B0/W35, energy class A+++
• quiet Copeland scroll compressor, R410A refrigerant (1.95 kg), stainless steel plate heat exchangers
• backup heater in three steps of 3/6/9 kW, power supply 400 V 3N~, circuit breaker 13–32 A depending on the heater setting
• GENESIS control with colour touch display, Modbus for building management, Smart Grid and Thermia Online web server
• passive cooling via the mixed circuit even without an expansion card; full cooling control and pool heating with the EM3 card

Placement and connection

The cabinet is 598 mm wide, approx. 710 mm deep and 1864 mm high; it weighs 187 kg empty and 377 kg with a filled cylinder, so it needs a solid floor. The antifreeze circuit (28 mm) is connected from the left, right or top, heating 28 mm, cold and hot water 22 mm – no flexible hoses required. The delivery includes an expansion vessel and filling device for the antifreeze circuit, a dirt filter with valve, 3 and 9 bar safety valves and an outdoor sensor.

Installation: The heat pump is designed with the HPC software; installation and electrical connection must be carried out by a specialist company.

Technical data

Frequently asked questions

What is included in the delivery?
Besides the heat pump: 3 and 9 bar safety valves, an outdoor temperature sensor, an expansion vessel and filling device for the antifreeze circuit, a dirt filter with shut-off valve, rubber sleeves and a pipe for connecting the antifreeze circuit. The IVAR.TER-PS connection fittings for the ATLAS range are ordered separately.

Why is a mixing valve needed on the hot water outlet?
Thanks to HGW technology, the water in the cylinder can reach up to 95 °C. A thermostatic mixing valve between cold and hot water lowers the outlet temperature and protects against scalding; alternatively, the hot water temperature can be reduced in the service menu.

Can ATLAS be used with a well instead of a borehole?
For a water-to-water source (groundwater or surface water) the WW version is intended, which already contains a built-in heat exchanger, a flow sensor and the EM3 card. This code is the BW version for a ground collector or borehole with antifreeze.

Which antifreeze is used in the primary circuit?
A mixture of water and ethanol with anti-corrosion additives and a freezing point of −17 °C (±2 °C). The heat pump itself contains approx. 2 l of fluid and the venting and expansion vessel approx. 3 l; the rest depends on the length of the collector.