the feed water heater mounted between the two right wheels of the car.  it is mounted under the splash guard between the running board and the car body.

The principal task of a boiler is to heat water into steam. In heating water into steam sufficient heat energy must be added to the water to turn it into saturated steam at the operating pressure of the boiler. The early Stanley cars simply drew water from the supply tank and pumped it into the boiler as needed. The steam is then consumed by the engine to do mechanical work and exhausted to the atmosphere.

Beginning with the 1912 model year Stanley added feed water heaters to their cars. The feed water heater not only acts as a muffler for the engine exhaust but it uses some of the heat energy in the exhausted steam to add heat to the water flowing in to the boiler. For non-condensing cars from 1912 through 1914 the feed water heater assembly was mounted in the burner exhaust pipe running to the rear of the car thus taking advantage of the combustion gasses to add additional heat to the water. With the water going into the boiler pre-heated the boiler doesn’t have to work as hard converting it to steam. A Stanley with a feed water heater typically sees a 15% to 20% improvement in economy and performance over the same car with the feed water heater not functional.



Stanley feed water heaters are constructed with water-carrying pipes inside an outer shell. Exhaust steam from the engine is piped in at one end of the outer shell where it can contact the exterior of the water-carrying pipes contained within. The water in the pipes absorbs heat from the steam. The steam and condensate then exit the outer shell at the opposite end from which it entered.

Feed water heaters generally contain 10’ to 20’ of water pipe depending on the model of car. As the feed water heater water pipe is between the pumps and the boiler it is subjected to the same pressures as present with the boiler and thus must be capable of withstanding 600 PSIG and higher water pressures. As a leak in the feed water heater pipe is difficult to diagnose (the water leaks into the area occupied by the steam and runs to the condenser and water tank) many Stanley operators keep a jumper pipe available to bypass the water circuit of the feed water heater if boiler water supply problems are being encountered.

Non-condensing car feed water heaters were shorter than those of condensing cars and to make up for the shorter overall length the water piping made four loops the length of the feed water heater before being discharged to the boiler. Condensing car feed water heaters passed the water to be heated the length of the heater and back before discharging it. For non-condensing cars the feed water heater was located along the left side of the car inside the burner exhaust duct. The heater was moved to the right side of the car alongside the pump box and splashguard for the condensing models.

© 2003-2012 www.StanleyMotorCarriage.com