WORTHINGTON — A Worthington family is breathing easier after replacing its furnace Tuesday morning and installing new batteries in all of its carbon monoxide detectors.

Bryant and Brittany Schroeder were at work — and their children at school — Monday when detectors began beeping throughout their Miles Drive home. Bryant, who’d had an opportunity to leave work early that day, arrived home around 2:30 p.m. to hear the alarms beeping when he stepped into the garage.

“The dogs were freaking out,” he said, noting how they bolted from the house when he opened the door.

The dogs stayed outside while Bryant walked through the house to investigate. There was no smoke, so he assumed a dying battery was to blame for the alarm sounding. Upon closer inspection of the carbon monoxide detector, however, he saw the blinking red message telling him to get to fresh air.

Bryant joined the dogs outside and, unsure what to do, called his father-in-law. His second call was to the Worthington Police Department’s dispatch center, and his third was to Minnesota Energy Resources, the local service provider who responds to gas leaks.

Within 10 minutes, a Minnesota Energy Resources technician arrived to check out the situation. By then, Bryant and his father-in-law, Doug Frisch, went through the house and opened all of the windows and doors.

As the technician went through the home, he found elevated levels of carbon monoxide.

“He went around the house, checking the furnace, the gas fireplace, anywhere gas can come from,” Bryant said. “Then he went outside and checked the vent at the back of the house. That’s when he found out it was coming from the furnace.”

A cracked heat exchange on the furnace caused carbon monoxide to fill the home, and the technician had to shut it down. The Schroeders, who spent the night at Bryant’s parents, replaced the 18-year-old furnace the next morning.

“We were told we could stay at home, but I had such a nasty headache from being in the home that I wanted to be out of there,” Bryant said. His father-in-law also complained of a headache after being inside the home briefly to help get the windows open.

Bryant believes that if he hadn’t arrived home when he did Monday afternoon, his dogs probably would have died. He’s also grateful that he got home before his wife and their two children, Braelynn, 7, and Brock, 5.

The Schroeders have five combination smoke alarms and carbon monoxide detectors in their home.

“We had new windows installed two years ago and it was their policy … to put new carbon monoxide and smoke alarms in each bedroom, the hallway, downstairs and upstairs living room,” Bryant said. “Otherwise, we might not have had the carbon monoxide detectors.”

The Schroeders shared their carbon monoxide scare on social media and, by Wednesday afternoon, Bryant said he’d heard that many of their friends were going to the store to buy carbon monoxide detectors.

According to information released by Minnesota Energy Resources, symptoms of carbon monoxide poisoning include sudden flu-like illness, dizziness, headaches, sleepiness, nausea or vomiting, fluttering or throbbing heartbeat, cherry-red lips, unusual pale complexion and unconsciousness.

“Carbon monoxide gas is produced when heating systems aren’t working correctly. You can’t smell, taste or see carbon monoxide. It can cause severe sickness and death,” the release stated.

If people suspect carbon monoxide poisoning, they should get everyone out of the house and into fresh air immediately, call 911 and open the windows.

Minnesota Energy Resources recommends people install and maintain carbon monoxide alarms on each level of the home and in each bedroom and replace them every five years. Also, people should have all fuel-burning appliances, flues, vents and chimneys checked regularly, never operate internal combustion engines indoors or use a charcoal grill indoors.