relac a/c system

Updated October 24, 2022 ... click on images to enlarge
For reference only, not an endorsement or guarantee.

RESTON RELAC LLC 
  System status updates:  http://www.restonrelac.com
  Typical cooling season:  May 22 noon through October 9 noon
  Cooling System Checklist and Diagram
  Residential Service Agreement
  Owner/Landlord Revert Form
  2012 VA SCC Tariff Rules, Regulations and Rates ... current
  Homeowner system check, service, and repair by appointment
  Emergencies ... (703) 608-9839 or (202) 421-7297
  Service ... (703) 349-3301
  Business ...  (703) 608-3882
  Plant ... 11485 Washington Plaza West, Reston, VA 20190
  Mail ... PO Box 2423, Reston, VA 20195
  comments@restonrelac.com ... primary email address
  Mark Waddell, President, Partner ... mark@restonrelac.com
  Michael Coleman, Operating Engineer, Partner
  Craig Nyman, Partner

AQUA VIRGINIA RELAC
  Ownership and operation prior to May 2013
  Cooling System General Information

HICKORY CLUSTER
  1974 Information on RELAC Cooling System
  2013 HCA Supplemental System RA DRB Approval Stipulations

RESTON ASSOCIATION
  Cluster Guidelines for Air Conditioners and Heat Pumps
  Amended Deed Section VI.2(b)(15)
  Maintenance and Use Standards Resolution 15
    2013 May Revision
    2014 June 12 BOD Item C. Issue Overview
    2014 June Revision

FAIRFAX COUNTY
  Noise Ordinance ... pending updated link

As reported on opening day in 1965, RELAC was " ... The world's first community air-conditioning system ... a major advance in the science of climate control ... ."

The Reston Lake Anne Air Conditioning (RELAC) system is based on a small central plant that cools and distributes highly chilled water to more than 300 single-family detached homes, multi-family homes, townhomes, condominium, and apartment residences, including Hickory Cluster, throughout the original Reston First Village.  The system typically operates from May through October each year, up to 24 hours a day. 

At the central plant, electric pumps send chilled water through almost two miles of insulated underground pipes to and from residences.  Then up to four large electric industrial chillers transfer heat from the sealed residential water loop to the sealed lake water loop.  Finally, more electric pumps send water and heat to Lake Anne and bring back cooler water to start the process over. 

RELAC eliminates the need for hundreds of ugly individual First Village residence outdoor heat pumps buzzing day and night.  Take a look and listen to the heat pumps at Parc Reston and you will understand why RELAC makes sense. 

Hickory Cluster Architect Charles M. Goodman also included a central plant, still serving 134 townhomes and 384 high-rise units, in his stunning 1962 River Park Mutual Homes community in Washington, DC.  And building owners continue to install and successfully operate the same type of system throughout the world today. 

In 1992, international resort owner and operator Club Med opened Columbus Isle, it's then flagship property, along spectacular Bonefish Bay beach on the west coast of San Salvador Island, Bahamas.

In this hot, humid, tropical Caribbean climate where air conditioning is a basic necessity almost 24 hours every day, all 236 one and two-story bungalow guest rooms, two restaurants, two nightclubs, a SCUBA and medical center, and numerous other public and private buildings are cooled by a single, central, chilled water plant similar to RELAC.

The Club Med system uses several evaporative condenser open-air cooling tower units similar to those approved by the RA DRB, delivered to RELAC in late 2012, and planned for possible future use.

Centralized cooling and heating plants are now called District Energy solutions.  One such system, NRG Energy Center Phoenix, provides  energy-efficient and environmentally sound district energy and/or combined heat and power services to buildings in downtown Phoenix and Tucson, Arizona, and on the Arizona State University campus, during searing 100F+ summer desert heat. The downtown Phoenix system started it all, beginning operation in 2001 by serving Bank One Ballpark, now called Chase Field.

With a reliability record of 99.9% since 2001, NRG Phoenix produces and distributes chilled water around the clock to customer buildings in the Phoenix central business district including several biomedical research facilities, high-rise condominiums, and office complexes. This system encompasses three main plants and two backup plants conditioning more than 12 million square feet of building space via four miles of chilled-water pipelines.  NRG Phoenix has demonstrated customer energy savings of approximately 13% after their connection to the downtown system.

In fact, in 2009 the International District Energy Association, identified more than 800 district energy systems throughout the nation.  Local systems similar to RELAC include Northgate Condominiums in Reston, Charles M. Goodman's River Park Mutual Homes noted above, Washington Reagan National Airport, Gallaudet University, Georgetown University, George Washington University, and University of Maryland College Park.

Although the basic RELAC system is as quiet, relatively efficient, and environmentally friendly overall as intended, it does not always work as well as it could.  One problem is that, depending on their distribution pipe loop location, not all customers receive chilled water from the RELAC plant at acceptable temperatures, pressures, and flow rates.  Failure of these same aging distribution pipes may also decrease system reliability and increase pass-through customer expenses.  Also, droughts and nearby golf course water use make Lake Anne a less and less efficient and reliable heat sink.

In addition, some critics consider existing RELAC central plant chillers to be old and inefficient, therefore adding to monthly customer bills.  RELAC says these chillers actually reduce some expenses because they are more reliable and easier to maintain than newer, more complex, and more expensive chillers.  But RELAC has plans to replace at least one chiller with a new and more energy-efficient model in 2015 to reduce costs.

Then there are legacy RELAC customer service and communication issues that have improved dramatically following the May 2013 transfer to local small business ownership.  And there are real or perceived differences in monthly expenses when compared to individual residence heat pump-chilled systems.

Another perceived issue is that a home served by RELAC is less appealing to potential homebuyers and that the lack of an individual air-conditioning system reduces property values.  However, many homebuyers and residents welcome the lack of additional $5000-10,000 mechanical equipment investment, maintenance, and annoying 70dB+ outdoor heat pump noise.  They seek out Goodman Houses for this very reason.  Especially since Goodman House small rear patios were not designed for large outdoor heat pumps, since installing required heat pump piping and wiring through thin lower level large window frames and rooms can be difficult, and since original utility room electrical panels will require upgrading or replacement to handle increased electrical loads.

Realtors who understand RELAC operation and benefits, like Hickory Cluster homeowner and Realtor Rob Chevez, are more knowledgeable and experienced at representing Hickory Cluster buyers and sellers than typical Realtors, and they welcome RELAC-served properties.  Reston homebuyers and sellers know that Hickory Cluster properties are highly desirable for many reasons, including designs by renowned Modern Architect Charles M. Goodman and 18 acres of mostly wooded Common Area, and that most Goodman Houses usually sell within 30 days on market, many times within zero to seven days.

However, a group of Reston residents unhappy with RELAC service and related RA restrictions formed Free From 15 in late 2013 to seek a 2015 referendum vote to revoke the RA covenant and allow current RELAC customers to freely choose, purchase, and install whatever air-conditioning system they prefer, subject to RA Design Review Board review and approval.  RA Members solidly defeated the 2015 referendum and a similar 2005 referendum.

But many serious problems blamed on RELAC are actually beyond RELAC control.

Many homes have excessive solar gain and heat loads, lack adequate wall or roof insulation, or are not sealed tightly enough to stop air, humidity, and energy leaks. 

Some homeowners do not regularly clean and maintain what can become clogged and moldy HVAC filters, air-conditioning heat transfer coils, and air ducts.  These photos show a 1986 air-conditioning coil unit at left, and a 90-degree lower return duct below, removed from a Hickory Cluster Goodman House and replaced in 2008.  The obvious lack of homeowner maintenance caused poor cooling, poor heating, excess humidity, and unhealthy air that typically contribute to allergy and respiratory problems.

Another big problem is that original Goodman House upper top floor duct systems were designed and installed during the early years of home air conditioning.  These supply and return ducts are undersized by current standards.  So it is difficult if not impossible to move enough cold air up, and enough warm air down, to cool top floor rooms well on very hot days.   Top floors can be 10F or so warmer than lower floors during summers.  The same thing occurs in reverse during winter months:  top floors are colder because they get less heated air from the same too-small top floor ducts.

In addition, even brand new, whole house, single fan/coil unit systems just don't cool or heat multi-floor, multi-zone residences well.  One option is to add ceiling-mounted room fans to help circulate available cool air.  But fans can cost $500-1000 including hardware and installation, and they are less effective as temperature and humidity levels rise.  Another option is to use RA-approved, portable, wall or floor-mounted fan/coil units in individual top floor rooms to overcome both undersized duct and multi-floor problems.  RELAC can be part of such a multi-zone solution by piping chilled water to and from similar units.  Portable, self-contained, vented refrigeration units, like the extremely quiet 36dB Sharp CV-P10MX product shown in this photo, are readily available in stores or online for less than $500.

The following inexpensive strategies will help reduce individual Goodman House RELAC summer season chilled water use and expense:
  Switch to pay-as-you-go metered service to monitor and reduce use
  Adjust metered chilled water flow to no more than 3 gallons/minute
  Adjust your expectations ... 78F is the top of the human comfort range
  Close and shade sunlit windows and sliding glass doors during hot days
  Use lower or middle floor rooms during hot days and nights
  Open windows to store cool air when temperatures are below 75F
  Close windows each morning when temperatures rise above 75F
  Inspect and clean cooling coils and ducts to allow unobstructed airflow
  Use interior magnetic flaps to reduce through-door mail slot air leaks
  Replace furnace fan filters at least monthly

If your budget allows, also try the following for more dramatic results:
  Re-roof with white surface materials to reflect sunlight and heat
  Install shade sails to shade upper floor roof terraces
  Install double-pane insulated windows to reduce heat and air infiltration
  Install top level stairwell awning windows to vent hot air when needed
  Use digital thermostat for slow, continuous circulation of stored cool air
  Use digital thermostat to limit RELAC use when away
  Install a variable speed whole house circulation furnace fan
  Install variable speed ceiling fans in bedrooms
  Install individual RA-approved top floor room fan/coil heat/cool units
  Enlarge undersized top floor supply and return ducts

Hickory Cluster residence calculated heat loads range from about 19,500 to 99,200 BTU.  Using some of the strategies noted above, a remodeled 2156 s.f. three-story Goodman House with primarily southern exposure glazing, a roof terrace, and 76,600 BTU calculated heat load uses RELAC chilled water only during days when outside heat index temperatures exceed about 90F, nighttime heat index temperatures exceed 75F, or when humidity exceeds about 70 percent.  The interior digital thermostat on floor two of three is typically set at 76-78F during very hot and/or humid days and nights. 

RELAC service charges can total more than $1000 total for a single customer residence during the May-October annual cooling season.  However, total annual metered RELAC bills for the Hickory Cluster residence noted above were less than $400 for each of the 2011-13 record heat cooling seasons.