Metro announced Wednesday that it will close one entrance to its Pentagon station to replace three escalators there.

Metro crews will begin replacing the three escalators on the southside entrance Monday, Feb. 4. Riders still will be able to enter the station via the north side escalators, or the elevator.

The escalators are 42 feet long and 18 years old, and finding parts for them is challenging, Metro said. Closing one entrance and replacing all three at one time will help crews get the work done faster, Metro said, but spokeswoman Caroline Lukas said there was no firm date yet for when the work will be finished.

The replacements are in addition to Metro's plan to install 128 new escalators across the system. The transit agency recently replaced escalators at Foggy Bottom and Dupont Circle, though riders are often frustrated that the new escalators shut down frequently because they are more sensitive to safety hazards. The new Dupont escalators were shut down 20 times in their first 40 days of use, The Washington Examiner previously reported.