Polyvalent Heat Pumps

Polyvalent and four-pipe heat pump systems both offer simultaneous or synchronised heating and cooling which makes them particularly versatile and efficient indoor temperature control devices.

They are also ecologically impressive. REHVA – the Federation of European Heating, Ventilating and Air Conditioning Associations has a useful explanation of the environmental and economic case for heat pumps.

It says polyvalent heat pumps are sustainable solutions and their main benefit is an ability to meet contemporary heating and cooling demands: “The capability of this innovative solution to exploit the potential free energy derived from the heat recovery can lead to significant savings in terms of energy consumption and fuel expenditure…

“Convenience increases when the hours of simultaneous request for heating and cooling grow.”

Are polyvalent & four-pipe heat pumps the same?

Polyvalent heat pumps and four-pipe systems don’t always amount to the same thing. In other words, all polyvalent heat pumps are four-pipe systems, but not all four-pipe systems are polyvalent.

Essentially, polyvalent heat pumps can achieve both heating and cooling simultaneously. Four-pipe systems also cover heat pumps that can switch between the two modes, but not necessarily at the same time.

How does a polyvalent heat pump work?

A polyvalent system is a clever solution to air conditioning requirements in systems where the heating demand is concurrently or independently combined with a cooling requirement from the building. They achieve this by making use of heat that is otherwise rejected as part of the production of chilled water.

Their ability to provide heating and cooling loads independently or simultaneously (not just seasonally, like reversible heat pumps) makes polyvalent units a promising technological solution, especially in the tertiary and commercial sectors. And polyvalent heat pumps are an exceptionally powerful weapon in the battle for decarbonisation.

A four-pipe heat pump system contains distinct return and supply lines that work as heating units and separate supply and return lines that work as cooling units. These systems work more energy efficiently when combined with a polyvalent unit.

How do four-pipe heat pumps work?

Four-pipe systems have individual units for return and supply lines that work as heating units and other individual supply and return lines that operate as cooling units. They comprise two independent water circuits – one with chilled water for room cooling, the other with hot water for heating.

This makes them ideal for use in temperate climates like the UK’s, particularly where there is no clearly defined seasonal operation. In fact, no summer/winter changeover is needed as cooling or heating can be produced at all times, and the control of the temperature of each room is independent of others.

Polyvalent heat pumps from Klima-Therm

Klima-Therm offers 25 air-cooled and 27 water-cooled polyvalent heat pumps to choose from, using non-flammable, energy efficient, low GWP R454B refrigerant gas.

The polyvalent range is especially flexible since it is suited to operate via two, four and six-pipe systems at any time of year. This intelligent solution to your air conditioning requirements is ideal for systems where the heating demand is simultaneously or independently combined with a cooling request from the building.

With unit operation down to an ambient temperature of -20°C, Klima-Therm-supplied polyvalent units are available with a huge range of accessories including EC fans, PFC, pre-painted coils, and vibration mounts.

One example of the polyvalent devices supplied by Klima-Therm is the Rhoss range which can satisfy cold and hot water demands simultaneously or independently within a single unit. Rhoss polyvalent heat pumps are equipped with total recovery for the production of cold and hot water simultaneously or independently throughout the year.

The use of a Rhoss polyvalent EXP system unit, alone or in combination with other HVAC systems (including chillers, heat pumps, etc.), can offer significant benefits in terms of reducing electricity consumption with an impact on carbon dioxide (CO2) equivalent emissions, operating and overall costs.

Air and water-cooled units are available from 5 to 800kW, including new Class A models with particularly high ESEER efficiency levels at partial loads.

Our highly experienced team of specialists can also offer valuable advice on the complete HVAC system and how to maximise its efficiency and cost-effectiveness. Contact us here to discover more.