Unlike many other Lennox dealers, Ilten's buys directly from Lennox Industries in Marshalltown instead of purchasing equipment from a distributor. Lee said Lennox has supported Ilten's through the years, replacing any defective units or components without question.

In the early 1970s, Ilten & Taege shortened its name to Ilten's Inc. at the urging of the late Robert Armstrong. He questioned why Taege was still part of the company's name, observing that dropping McClenahan from Armstrong-McClenahan didn't harm business in succeeding years.

In 1972, Ilten's received the heating and cooling contract for four new elementary schools - Van Buren, Nixon, Squaw Creek and Jackson. It also moved its manufacturing operations to a separate building on Ninth Street SW. Ilten's also sells appliances and fireplaces, but heating and air-conditioning equipment remains its dominant business.

As Ilten's enters its third century of business, the Ilten family is confident that a fourth generation will carry on.

Ilten's is now owned and operated by John, Jack and Tim Ilten.