Air Source Heat Pumps

Configuration & Installation

This shows a typical configuration including optional sanitary hot water tank and optional cooling. The split system consisting of an outdoor unit and an indoor hydro-box that can be connected to all standard low temperature radiators and underfloor heating systems. The four main components are described below.

  1. Outdoor Unit
  2. Hydro-Box
  3. Sanitary Hot Water Tank
  4. System controls

1. Outdoor Unit

The outdoor unit extracts free low temperature heat from the surrounding air and increases its temperature. Upgraded heat is then transmitted via the refrigerant circuit to the indoor hydro-box.

2. Hydro-Box

The indoor hydro-box transfers the heat in the refrigerant to the water circulated in the central heating radiators, underfloor heating system and sanitary hot water tank. In the combined heating and cooling version of the indoor hydro-box cooling is achieved by reducing the water temperature to 4°C and circulating it through fan coil units. The system can also provide moderate cooling via the underfloor heating system by limiting the lowest water temperature. The preparation of sanitary hot water is performed by switching the system from cooling or heating to sanitary mode.

3. Hot Water Cylinder

A purpose built stainless steel water tank, constructed to maintain the highest levels of energy efficiency, is available to meet all hot water needs. The combination of an electric booster heater in the upper part of the tank and a heat pump heat exchanger in the lower part ensures the lowest possible energy consumption with rapid water heating. In addition, a built in function raises the water temperature to 70°C or higher at least once a week to remove any possibility of Legionella growth.

4. System controls

System controls are contained within the hydro-box and feature a weekly timer that enables the indoor temperature to be controlled according to the user requirements. The timer is programmable on an hourly or daily basis so that temperatures can be reduced at night or during holidays and increased prior to rising in the morning or returning home. User comfort according to personal preference is thus maintained at all times. Where control over individual room temperatures and comfort levels is needed a conventional room thermostat should be added.