Retrofitting apartment buildings for fuel savings.

As rising fuel prices increase the operating costs of multifamily dwellings, owners and managers are retrofitting their properties with technologies that improve energy efficiency.

Their approach has broadened to include 1) the elimination of fuel and water waste, 2) lowering the cost of maintaining heating and domestic hot water systems, and 3) reducing the amount of management time needed to achieve these goals. In addition, the technology chosen should be economical and easy to install.

Fuel Savings

There have been many buildings--notably low-income 401 properties--where excessive heating costs are due to antiquated monitoring and control of boiler cycling and domestic hot water systems. However, owners and managers of these and other properties, including middle-and upper-income rental buildings, condos, and coops, are turning to low-cost computer technology to reduce their fuel bills by as much as 40 percent or more.

They have installed Fuel Computers supplied by U.S. Energy Controls, which, by means of outdoor and indoor temperature sensors and electric and electromechanical controls, permit boilers to cycle only when building interiors actually need heat.

Besides saving considerable sums for building owners and managers, this technology enhances tenant satisfaction. During the heating season, New York City municipal ordinances require that between 6 A.M. and 10 P.M., when outdoor temperatures are below 55 degrees F., interiors must be heated to 68 degrees F.

At buildings that still use antiquated boiler controls that respond only to outdoor temperatures, boilers continue to cycle as long as outdoor temperatures are below 55 degrees F. Therefore, interiors become overheated--often to temperatures well above 80 degrees F. Tenants throw open their windows to cool off and suffer from the cold drafts that rush in. Meanwhile, landlords pay for the heat wasted to the out-of-doors.

With programmable Fuel Computers, this waste is eliminated. Landlords' fuel savings give them the option of maintaining interior temperatures higher than legally required, thereby improving occupants' comfort and landlord-tenant relations.

Lower Maintenance Costs

Many building owners, supers, and some management people do not have a detailed knowledge of heating and domestic hot water systems. They may be unaware of warning signs of system problems and/or the most cost-effective ways to deal with them. In some cases, this can lead to neglect of serious malfunctions (e.g. condensate-return line leaks in steam heated buildings that can waste vast quantities of water day after day) and/or incorrect diagnosis and maintenance.

Fuel Computers solve these problems by monitoring key functions, including stack temperature, return-line temperature, flame failure, oil consumption, water consumption, premix boiler water temperature, and domestic hot water temperature.

Typical of the value of this information is the way it can be used to forestall or resolve domestic hot water problems in buildings that have tankless hot water systems.

If the computer indicates that the water is too hot, the super will be alerted to adjust the mixing valve to lower the water temperature (if this doesn't work, the super can check with management about repairing or replacing the valve).

Without this computer input, excessively hot water will destroy washers in hot water faucets and cause the faucets to leak. Supers tend to respond by replacing the washers repeatedly while the underlying problem is not corrected, which results in a waste of water and beating fuel.

If the computer indicates that the water is not hot enough, it alerts the building super to check the water level in the boiler and add to it, if necessary, or adjust the mixing valve to increase the water temperature. In this way, tenants' complaints about inadequate domestic hot water can be forestalled. Unjustified complaints can be proven incorrect by showing the tenants computer records of water temperature.

This synergy between Fuel Computer information and building supers' response exists with respect to every heating and water parameter monitored by the computer. It can save thousands of dollars annually in maintenance and repair costs at a single multifamily dwelling.

Oversight and Control

Fuel Computers give owners and managers even more information and control than if they were actually onsite in their buildings. Physically, a Fuel Computer consists of a monitoring and control unit and its associated sensors.

It is housed in a compact cabinet, usually mounted on a basement wall. By installing a Fuel Computer in each of the multifamily dwellings it manages, a management firm can oversee and control the heating and hot water systems in scores of buildings from one office location. The fuel and management savings from this type of control can total hundreds of thousands of dollars annually.

Each Fuel Computer is linked to an owner's or manager's office by Windows 98-based telecommunications software. Managers' control includes the ability to phone the computers to set day and night apartment temperatures, domestic hot water temperatures, and other parameters.

Incoming messages from Fuel Comuters cover all the parameters monitored, and are recorded on a PC. Often, management firms poll the computers every morning to get up-to-date information as well as data stored for previous days' operations.