Quick Facts

NamePEPCO No. 43
Manufacture Date1938
Railroad Of RecordPEPCO
ManufacturerHeisler Locomotive Works

Description

About the PEPCO No. 43:

The PEPCO No. 43 was built by Heisler Locomotive Works and purchased new by the Potomac Electric Power Company, or “PEPCO,” in 1938. It is a rare type of “fireless” – or “thermos-bottle” – steam locomotive. These engines had no fuel-burning fireboxes to generate energy; instead, they had to “recharge” at large steam plants. During these recharging periods, the locomotive’s boiler was filled with “superheated water” that had been pressurized to reach temperatures of about 400 degrees F. When the boiler was filled to about ½ or ¾ capacity, the superheated water was “charged” with 250 psi of steam. For the PEPCO No. 43, the entire process would take just about 10 minutes. 

Once the locomotive was charged, the steam in the boiler pushed the engine forward. When the steam was gone, the pressure within the boiler dropped, causing the superheated water to boil and generate more steam. A fully charged thermos-bottle locomotive could only operate like this for a few hours on a single charge. This meant that all fireless locomotives had to operate within a short distance of their “home” stations. Thermos-bottle locomotives may be considered an early form of green technology: while fuel-burning steam engines emit hazardous smoke exhaust, fireless locomotives only emit steam vapor. 

Most fireless locomotives in the United States were used to push loaded coal cars around large-scale utility stations, like those owned by PEPCO. Because they were used for such specialized tasks, very few fireless locomotives were ever made. Heisler Locomotive Works only produced 50, and that was more than any other manufacturer in the nation.   

From 1938 to 1978, the No. 43 was used to haul coal, first at the Buzzard Point Power Station in Washington, DC, and then at the Potomac River Power Station in Alexandira, VA. At some point during its 40 years with the power company, the locomotive was renumbered as the PEPCO No. 1. Though the No. 1 was still in good condition when it retired in 1978, it was not strong enough to pull the newer, heavier coal hoppers of the late-1970s. 


Virtual Tour:


Visual Tour Description:

Exterior

The PEPCO 43 has a black exterior on the boiler and cab. The railings, cab detailing, and wheels are a bright yellow. Painted in this same yellow shade is Potomac Electric Power Co. along both sides of the boiler and No 43 on both sides of the cab. On the front of the boiler is a single circular light as well as a small plaque reading Heisler No 43. The cab features two square windows on either side and two trapezoidal windows on the front of the cab.

Interior 

The interior of the cab is a pale grey with dials and levers painted black. The cab is fairly small, leaving room for a minimal crew.

Climb inside the B&O No. 4500 “Mikado”

December 26, 27 & 30

2025

New Monthly Tours!

Go Inside the B&O No. CE-15 Tunnel Clearance Car!

January 15, 18 & 19

Climb aboard the B&O No. CE-10 Electric Switcher!

February 19, 22 & 23

Climb inside the GC&E No. 1 “Shay”

March 19, 22 & 23

Purchase a B&O Membership

for the ultimate ticket to explore every hidden gem in the series!

Did You Know?

The first passenger train ticket in the United States was sold on our historic site in 1830.

Vicki A.
Brunswick, MD

This was an amazing museum to visit! A must see in Baltimore. Starting with the ease of parking...Right onsite and FREE!

Close Search