 -- A mother of two boys was touched by a selfless act of kindness when her local repair man fixed her furnace free of charge.

Bridget Stevens returned to her Pittsburgh-area home earlier this month and realized her furnace was not functioning.

Stevens' story, which she shared on Facebook, has now gone viral.

Stevens texted her husband, Bobby, who is deployed overseas with the National Guard. When Bobby couldn't figure out what to do, she called Betlyn Heating and Cooling in Moon Township, Pennsylvania. Owner Paul Betlyn immediately came to the rescue.

Betlyn, who has been in the business for more than 30 years, fixed the furnace quickly. Although the repair normally would have cost approximately $150, Betlyn said he decided to do the job without charging Stevens. He wrote on her bill, which came up to $1, that she received a "deployment discount."

In her post, Stevens noted, "[Betlyn] said that the $1 was a joke and to thank my husband for his service."

"I was completely overwhelmed and in shock when Paul handed me the slip," Stevens told ABC News. "I didn't really know what to say, and I still have a hard time finding the words to truly express my appreciation."

Betlyn, 65, told ABC News his late grandfather, who is also named Paul, taught him about the importance of helping others and giving back to the community.

"My grandfather was a milkman during the Great Depression and many times he'd go to the door and the woman didn't have any money for milk. But the baby was crying in the background. So he'd put the milk on the table," he explained. "And when I heard about Bridget with her husband being deployed...I put the milk on the table."

Betlyn insisted that what he did was nothing special. "I'm not the hero here. The deployed, they're the heroes," he clarified.