Pressure reducing valves of the 1920's provided acceptable performance but lacked accuracy and speed. They also had a tendency to seize up and require a great deal of maintenance during normal service life. Lack of performance and frequency of maintenance calls helped drive demand for a better performing regulator. In 1925 Paulsen Spence designed the first normally closed, pilot-operated, diaphragm actuated pressure regulator, the Spence Type ED.

The Spence type ED pilot-operated pressure regulator revolutionized the way energy producers supplied low-pressure steam to their customers by providing greatly improved accuracy in pressure control. Accuracy, dependability and low maintenance costs soon made pilot-operated regulators the standard throughout the steam industry. This method of steam reduction and distribution is still one of the most accurate methods of HVAC and process control available today.

Paulsen Spence started his career as a manufacturer's representative, selling pressure-reducing valves in the New York City area. In 1926, shortly after filing a patent application for his design, Mr. Spence and his business associates met with Leon Dexter, owner and operator of the Rider-Ericsson Engine Company of Walden, NY, who agreed to share his production facility with the new entrepreneurs. The Rider-Ericsson Company was founded in the 1870's by Captain John Ericsson, inventor of the hot air machine, the screw propeller and, the famous U.S. Navy ironclad ship, the USS Monitor.

Orders for Spence products grew steadily throughout the late 1920's and mid 1930's. The company's product offering expanded to include a full line of pilot-operated and direct-acting regulators for pressure, temperature, and backpressure control, desuperheaters and strainers. By 1939, Spence regulator sales surpassed the sales of the Rider-Ericsson products. Paulsen Spence purchased the plant and manufacturing equipment from Leon Dexter. During this period, Spence regulators were being used extensively in manufacturing facilities throughout the United States. Demand for these products was so great that, during the Second World War, the U.S. Government restricted the sales of Spence steam pressure reducing valves to the government and their sub-contractors because Spence regulators were vital to the production of essential war materials. In recognition of the company's contribution to the nation's war efforts, the Spence Engineering Company received the coveted Army-Navy "E" Award for production efficiency.

Spence continues its "History of Innovation" by continuing to develop and manufacture quality steam specialty and fluid control products and solutions for the HVAC and industrial marketplace. Spence has introduced several innovative, cost-saving products to the HVAC and industrial process markets including the type "J" Series Pneumatic Control Valve (1986), "Nova" NFT Series Variable Orifice Steam Traps - the first "Made In The USA" float steam trap (1992), CDH Series patented thermostatic sanitary steam trap (2001) and the "CoMBo" CME Series - the industry's first condensate measuring elbow thermostatic steam trap (2006).
Throughout its history, Spence Engineering has continued to broaden its product offering and improve its manufacturing capabilities through process improvements and strategic market acquisitions. Recent, notable developments include:

By early in this decade Spence Engineering Company owned half of the market for pilot-operated steam regulators

Spence manufacturing facility moved to its current 79,000 square foot location in Walden, NY

Spence family sold the company to Watts Industries, a well-established valve manufacturing corporation with a strong presence in the HVAC market

Spence acquires the Nicholson Steam Trap line of industrial and process steam traps

Spence Engineering Company takes over the manufacturing of safety relief valves, from the Watts Industries Canadian division, and becomes certified by the American Society of Mechanical Engineers (ASME) as a manufacturer and assembler of safety relief valves

Fueled by a reputation for building quality products, Spence sales more than doubled from $6.7 million to $14 million.

Spence acquires the Series 2000 line of Temperature Regulator from Ashcroft.

Spence Engineering and Nicholson Steam Trap receive ISO-9001 certification as manufacturers of fluid control and steam specialty devices

CIRCOR International, of Burlington, MA, acquired the HVAC, Oil & Gas, and Instrumentation divisions of Watts Industries including Spence Engineering.

Spence acquired the RXSO Rockwood Swendeman line of cryogenic safety relief valves

Spence Engineering incorporates "Six Sigma" lean manufacturing practices at its Walden, NY facility