PITTSBURGH (KDKA) – More than a dozen families will stay warm this winter, thanks to the generosity of others.

Volunteers did the heavy lifting at a home in Carnegie over the weekend.

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They spent the day installing a brand new furnace for the Dunmyer family. The family was selected as one of 13 in Allegheny County to receive a new heating system free, from Tudi Mechanical Systems.

“We have a lot of health issues and just to be able to know that we’re going to be warm and someone’s doing something so kind for us, it’s just unbelievable,” Mary Cay Dunmyer said.

“To be able to get a new furnace, we weren’t going to be able to swing it ourselves and when Tudi came along and said ‘Hey, we would like to do this for you.’ It’s just amazing,” Jack Dunmyer said.

A friend nominated the Dunmyer’s for the 17th Annual Heat for the Needy charity event.

Through the program, Tudi employees and their families volunteer their time and effort to deliver and install new furnaces in the homes of those in need.

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The day is often referred to as the “one day miracle.”

Mary Cay Dunmyer said she was stunned when she got the call that her family was selected.

“It’s just hard to believe because sometimes you get down on your luck and you know when something good happens for a change, it’s pretty cool,” she said.

“A lot of people say pay it forward. These people actually do and it’s very impressive,” Jack said.

Tudi has provided the Dunmyers with not only heat, but peace of mind and hope.

As for the volunteers, they certainly don’t walk away empty-handed.

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“It’s a great feeling. I mean, all the volunteers with us today and out in the field, it’s a good feeling,” Frank Iozzo said.