The dangerous cold puts a heavy burden on your furnace. Many aging systems can't keep up or break down altogether. That's keeping HVAC technicians busy making house calls while homeowners wait in the cold for repairs or even replacements.

On Tuesday morning, Julie Dorsett woke up to 60 degrees inside her Greenwood home. The furnace in the garage is still running, it's just not keeping the home comfortably warm.

The furnace is the original in the home from when it was built in 1995.

"It's a dinosaur," said Mister Quik HVAC technician Thomas Herman, who made the service call. "It has definitely outlived its life expectancy."

"I just hope that it doesn't die," said Dorsett. "It's an old furnace, so that's my main concern. It seems like we had a fairly mild winter and now we're in for a big shock."

After Herman's evaluation of the furnace, he advised Dorsett that the 24-year-old furnace needs a new blower motor or be completely replaced.

"The blower wheel has all that dirt accumulation on it," said Herman. "The bearings are weak on the blower motor. It's just not pushing enough air flow across that heat exchanger."

The Mister Quik checkup brought the temperature back up to 68 degrees inside.

"That's my biggest concern," said Dorsett. "Will it get too cold that I have to worry about my pipes?"

Mister Quik provides plumbing and heating service. Calls were up about 25 percent over normal Tuesday.

"I expect to be going non-stop for the next few days," said Herman.