Colt’s revolutionary Water Refrigerant Flow (WRF) air conditioning system, Caloris, is being installed as part of an energy efficient refurbishment at the Ramada Heathrow hotel. Chosen for its compatibility with Ground Source Heat Pump (GSHP) technology, plus its energy, cost and space saving qualities, Caloris will also provide air-source back up to the GSHP system.
Colt Caloris units will be installed in all 200 rooms at the hotel, with two outdoor units linked to GSHP. The hotel’s re-development is due for completion in August 2008.
In addition to its compatibility with GSHP, Colt Caloris’ design makes it perfect for hotel applications. Caloris offers de-centralised, local control, adjustable by individual room occupants, and its indoor, horizontal units are amongst the quietest and slimmest on the market. 
Unlike VRF (Variable Refrigerant Flow) air conditioning systems, Colt Caloris units are connected by a two-pipe neutral temperature water circuit, resulting in a minimal amount of refrigerant charge being used, avoiding the F-gas regulation. The minimal use of refrigerant also negates the need for potentially costly refrigerant leak detection systems. At Ramada, this has vastly increased the available space – rooms that would have been required to house refrigerant to water heat exchangers in a VRF system are used, instead, to store linen.
GSHP technology can be one of the most energy-efficient ways of heating and cooling buildings, achieving a very high Energy Efficiency Ratio (EER). Since Caloris achieves a maximum EER of up to seven, the combined technologies are an extremely energy efficient partnership.