DENVER -- Most people try to stay indoors to stay warm when temperatures hit single digits, even below zero. But some travelers said the indoor temperature inside Denver International Airport feels as if they are outside.

Temperatures inside Concourse B are in the 40s.

"You can see your breath," said Jeremy Schoemaker, who was waiting for a flight home to Nebraska.

Schoemaker was waiting with his wife who was wearing a parka, ski hat and gloves to stay warm.

"We packed everything (in our carry on) -- our hats, our gloves, thinking it would be warm," said his wife, J. Schoemaker. "We whipped it all out."

The Schoemakers said they moved from the end gate, B95, to the middle of the concourse, where they said it was warmer. However, they missed their flight because they didn't hear the boarding call after moving to the warmer area of the concourse.

7NEWS took a thermometer inside the concourse. The warmer section the Schoemakers sat in fluctuated between 50 and 55 degrees.

The cold temperatures are in the lower terminal, which serves United Express flights that fly out of gates 81-95.

"They keep delaying it," said Jeremy. "So we keep going down there and seeing how delayed we are and then come back here because it 15 degrees warmer up here."

The closer passengers get to Gate 95 the colder it gets.

"It's freezing," said Naomi Grimsley, of Oregon. "We can see our breath in here."

Near Gate 95, 7News' thermometer measured the temperature between 46 and 53 degrees.

"We thought it was a ploy to sell more coffee," said Grimsley. "But I guess that is not the case."

A spokeswoman with DIA confirmed a pipe that feeds a heating system inside the Sky West breakroom broke. It's a custom made unit and will take time to repair or replace. DIA said the heater is not affecting travelers, only employees in the break room.

Passengers disagree. Many are bundled in jackets, scarves, gloves, hats -- anything to stay warm.

DIA said the cold temperatures are from the outside air seeping in through the jetways, not the broken heater.

Either way, the heater will not be fixed by Wednesday and the cold weather will still be around, so passengers flying out of Concourse B, on a regional flight, should dress warmly.