Frankfurt’s city council is leading the way in environmental protection: by converting the air-conditioning system installed at its town hall (referred to as the ‘Römer’) to the non-ozonedepleting refrigerant DuPont ISCEON MO29, it has become a leader in the withdrawal from service of R-22 refrigerants, which contribute to ozone layer depletion.

The conversion (or ‘retrofit’) of the water chiller system took place without a hitch back in September 2007, as part of routine maintenance procedures. Technicians from the air-conditioning system supplier TRANE Deutschlan GmbH, of Duisburg/Germany, replaced a total of 45 kg of chlorous R-22 refrigerant with ISCEON MO29. The easy-to-use, non-ozone-depleting HFC refrigerant is designed to replace R-22 in existing direct expansion water chillers for air conditioning systems in residential and commercial premises, as well as medium and low temperature refrigeration systems.

“It was the thirteenth retrofit for our technicians using ISCEON MO29,” says Kai Schorn from TRANE, who was responsible for carrying out the conversion. “And, as with the previous twelve, it was carried out without a hitch and in the shortest of times. As part of routine maintenance procedures, an expansion valve was replaced and the seals and mineral oil were renewed.”

Frankfurt’s city council had responded early to new regulations, due to come into force as of 1 January 2010, which will ban the refilling of existin refrigeration systems, for service purposes, with virgin R-22. Accordingly, as of 31 December 2009 – at the latest – the sale of this widely-used refrigerant will be suspended by producers and stockists. Thereafter, either recycled R-22 must be used, or the conversion to an alternative refrigerant carried out. There are also problems with current reserves of prepared R-22, which are not expected to be sufficient to meet projected demand after 2010.

It is for this reason that experts, such as TRANE, recommend all system operators to convert today all existing refrigeration and air-conditioning systems to an alternative, non-ozone-depleting refrigerant such as ISCEON MO29. This will help avoid shortages and time-pressure created by the limited conversion-capacity of refrigerant contractors

The ‘Römer’ in Frankfurt has been used as the city’s town hall for over 600 years and forms one of the best-known row of buildings in Germany. Many events of national and local significance are associated with the buildings. Many sporting heroes, for example, have celebrated with their fans in the town-hall square from its balcony. The ‘Kaisersaal’ (banqueting hall), meeting rooms and additional offices are air-conditioned using a water chiller from TRANE, its GWD109 model dating from 1990, which is installed in the cellar. It has a single refrigeration cycle and one compressor, and is filled with 45 kg of refrigerant. Its refrigerating capacity is 270 kW.