It isn't just Metro's rail cars that can get hot. The underground stations where riders wait can become toasty, too, when outdoor temperatures spike.
Metro's 47 underground stations have chiller units that help cool the stations from May 15 to Oct. 15 each year. They cool water for station air conditioning systems, designed to keep stations six degrees cooler than the outdoor temperatures.
The life expectancy of an individual chiller unit is about 21 years. But in the past, nearly half of the accompanying equipment was more than 30 years old, according to a Metro report slated to be presented to board members Thursday.
The units are working against the elements as the stations' exits remain open to outside air, so it's like trying to cool down a house with the door open. Brake dust and humidity stress the machines. To make matters worse, the air conditioning units that keep the insides of trains cool generate heat that fills the stations.
Metro has been replacing parts and has overhauled 17 of its 51 chiller units in just over two years. It plans to have all the air-handling units, as well, updated by the end of June.
And the agency hopes to replace a chiller unit at the Tenleytown stop as part of a Safeway mixed-use development.
The unit is on a quarter-acre of high-value land. The agency wants to sell the spot to the developer, Clark Realty, but have a new chiller unit included in the project. That rail station isn't one that riders have typically complained about being hot, though, says FixWMATA.com, which tracks them. Farragut North, Ballston and Rosslyn received 19, 11 and 10 complaints respectively last year on the blogger's list, while no one filed complaints to the site about Tenleytown.