Noll, who had been under a doctor's care for an undisclosed illness, was 82.
His wife, Marianne, found him unresponsive at 9:45 p.m. and called 911. Paramedics pronounced him dead 10 minutes later.
In recent years, Noll suffered from severe back pain that limited his mobility and forced him to walk with two canes.
Noll served as Steelers head coach for 23 seasons from 1969-91, winning Super Bowls after the 1974, '75, '78 and '79 seasons and guiding what is considered one of the greatest sports dynasties ever.
His 209-156-1 record and record four Super Bowl titles earned him induction into the Pro Football Hall of Fame in 1993, his first year of eligibility.
“Chuck Noll is the best thing to happen to the Rooneys since they got on the boat in Ireland,” said Art Rooney Jr., the oldest son of Steelers founder Art Rooney Sr.
Noll was known for choosing his words carefully. His oft-repeated remark, “Whatever it takes,” was short and succinct. It became the slogan for his coaching career.
Noll inherited a franchise that had won 18 total games the previous five seasons, and his first team finished 1-13.
But by the end of Noll's fourth season, the Steelers had advanced to the AFC championship game. Two years later, they were Super Bowl champions.
Steelers Hall of Fame wide receiver Lynn Swann said Noll “never gets the credit he deserves for managing one of the great teams in NFL history.”
Noll was a perfectionist and loved to teach, those who worked with him said.
“He was really knowledgeable about any and all things,” said Hall of Fame coach Don Shula, who hired Noll in 1966 to be member of his staff with the Baltimore Colts. “We used to kiddingly call him Knute Knowledge,” a nod to former Notre Dame great Knute Rockne, considered one of the greatest football coaches of all time.
Rooney Jr., who headed the Steelers' scouting department from 1971-86, likened Noll to “the toughest professor you ever had.”
“He was not a pizzazz guy. He knew where he was, where he was going and where he wanted to go and how to do it,” Rooney Jr. said. “He had a very, very strong moral compass. ... My dad respected that.”
Noll was a reluctant celebrity and turned down only one interview request, longtime Steelers publicist Joe Gordon said. That came from Howard Cosell.
“He never really considered Cosell a serious journalist,” Gordon said. “Any other time, regardless of the circumstances, he was always accommodating.”
Noll rejected many offers to appear in commercials, some of which could have been financially lucrative, Gordon said.
“He preferred to be a football coach and not a celebrity,” Gordon said. “After a while, they stopped calling because they knew he wasn't interested. If he would have had his way, after the game on Sunday, he would have just picked up his briefcase and gone home.”
Noll was loyal to his assistants and those who worked around the team at Three Rivers Stadium, said former defensive assistant coach George Perles.
“He always took the grounds crew people on the plane to away games and the families to the championship games,” he said.
Born in Cleveland on Jan. 5, 1932, Noll attended Benedictine High School, where he played running back and tackle before earning all-state honors and a football scholarship to the University of Dayton.
At Dayton, he played tackle and linebacker before being drafted by the Cleveland Browns in the 20th round in 1953. Chosen as a linebacker, Noll was converted into a messenger guard by legendary coach Paul Brown. Noll alternated with another player at running plays into the huddle.
“After a while,” Brown once said, “Chuck could have called the plays himself without any help from the bench. He was that kind of football student.”
Noll played through 1959, when he decided to retire at age 28 to pursue a job opening on the Dayton coaching staff.
Before Noll could accept the job, however, he was hired by coach Sid Gillman, and he spent six seasons with the Chargers through five AFL Western Division championships.
Noll, a food and wine connoisseur who flew his own plane and sailed his own boat, separated his personal life from football.
His family lived in Upper St. Clair for many years, and Noll's son, Chris, played football and soccer at the high school. Noll seldom attended the games, but his son said it was not from lack of interest.
“They were trying to give me my space,” Chris Noll said. “They would sneak in once in a while. They made a decision not to put that kind of pressure on me.”
The younger Noll remembers coming home from football practice as a freshman and telling his father the team needed a long snapper.
“He took me out in the driveway and showed me how to do it,” he said.
Chris Noll, director of communications at Miss Porter's School, a private, all-girls institution in Farmington, Conn., where he also has been a teacher, soccer coach and computer specialist, said his father seldom talked football at home.
“After (Steelers) games, we would stop someplace to get something to eat, and we didn't talk about the games at all,” he said. “It was a pretty clear separation.”
Longtime assistant coach and former Steelers running back Dick Hoak said Noll maintained certain values, and family came first.
“That came before football, and football was after that,” Hoak said.
Many times, when the NFL Draft lasted until late into the night, Noll ended the day by bringing out his favorite bottles of wine and sharing them with team officials and reporters. He also enjoyed discussing politics and loved classical music and photography.
“He was very intelligent,” Hoak said. “He knew a lot about a lot of things.”
One year at training camp, he conducted the Pittsburgh Symphony during a live performance.
“He relished the opportunity,” Gordon said. “I never saw him so happy as when he was conducting the symphony.”
In addition to his wife, Marianne, Noll is survived by his son, Chris; and two grandchildren, Katie, and Connor. John A. Freyvogel Sons Inc. on Centre Avenue in Shadyside is handling funeral arrangements.
--Jerry DiPaola, Pittsburgh Tribune-Review
Copyright 2016 Nexstar Broadcasting, Inc. All rights reserved. This material may not be published, broadcast, rewritten, or redistributed.