Upping efficiency with thru-wall cooling - evaluation of Packaged Terminal Air Conditioners

Real Estate Weekly, August 19, 1992 by Sidney Siegel

New York is known as the world capital of many things - finance and commerce are prime examples. We in the real estate, construction, building management and allied fields are also well aware that New York is the pre-eminent market for high-rise, multi-family apartment and hotel buildings.

A feature of many of these buildings is the use of thru-wall cooling and heating units (Packaged Terminal Air Conditioners, or PTACs). In fact, the New York Metropolitan area is the leading market in the world for hydronic PTACs - units using steam or hot water as a heating source, combined with a thru-wall cooling unit within a single cabinet or "package". New York's savvy builders discovered long ago that this combination of hydronic heat with electric cooling presented a winning combination - low front-end purchase and installation costs: a "zoned", individually-controlled system of heating and cooling and long equipment life are just a few of the features that have pushed PTACs to their pre-eminent market share within the New York region. Packaged Terminal units have been in widespread use since the late 1940's, although these early units were little more than thru-wall A/C units with a heating coil and cabinet. Significant advances have been made through the years in terms of reducing noise levels, improving heating controls and, in recent years, Increasing the energy efficiency of the units available on the market. This last trend has gained additional momentum recently with the inclusion of Packaged Terminal Air Conditioners within the Con Edison "ApplePower" rebate program, which currently provides for an $80. per ton (12,000 BTU) rebate for units which meet Con Ed's stringent energy-efficiency standards and are used on qualifying projects. This is a factor that will most likely increase in significance, as utility companies strive to cut energy consumption during peak periods (eg. summer cooling) and reward the users of energy-efficient equipment. The rewards can be significant - a builder using Ice-Cap's new "CTC" line of high-efficiency heating/cooling units recently obtained a rebate of more than $90,000 on a single project. These high EER (energy-efficiency ratio) units, used with a steam, hot water, heat pump or electric heat source, are the wave of the future within the New York area and we find an increasing interest on the part of developers, real estate managers and consumers in these new, high-efficiency products.

Hotels are a market where advanced control systems and high unit efficiencies are of particular concern, as energy is reported to be the second highest overhead cost within the hotel industry. Many of New York's hotels have older, obsolete PTACs currently installed, and there is widespread interest in upgrading this equipment. There are a variety of replacement available - including those manufactured by General Electric, Fedders, Remington, Singer, AAF, ZoneAire, Embassy, WeatherTwin, among others. A second option is a complete new installation - making a masonry cut, installing a new wall sleeve and a new heating/cooling unit. This method allows for the use of the most modern, efficient equipment available, but is obviously a more expensive process than simply replacing the existing air-conditioning chassis. Many hotels and apartment projects have opted for an "in-between' method in which the hydronic heating assembly, room cabinet and air-conditioning unit are replaced, but the existing wall sleeve and exterior grille are left in place. This allows for a complete upgrade of the heating/cooling system and provides an improved, modernized room cabinet, without the additional cost of a new wall cut.

Whether your particular needs involve the rehab of A single apartment or the construction of a "mega" project, the upgrade of an entire hotel's cooling and heating system or the replacement of a single, obsolete piece of equipment, there is a strong incentive to use the most efficient, quiet and most attractive products available.

With the increasing awareness of the need to cut energy costs and conserve our natural resources, New Yorkers are demanding greater efficiency in every type of product used, and Packaged Terminal Air Conditioners are no exception.