COAL CREEK CANYON, Colo. - Coal Creek Canyon residents Morris and Nancy Berton have lived in their home for the last 23 years.
"It's beautiful," said Nancy.
But living at nearly 9000 feet above sea level brings complications, including heating the couple's house.
Natural gas is lighter than air. At higher altitudes, where the air is thinner, a greater volume gas is needed to provide heat for their mountain top home.
To help deal with the extra cost, utility companies, like Xcel Energy use a special formula taking into account a homeowner's altitude to help make gas service more affordable, because they will need more volume.
Yet at the end of 2011, a higher than usual bill caught the couple's attention.
"It may have gone up $10, $15 for that particular month, so that lead me to investigate why," said Morris.
Here's the problem: During a review of its records, Xcel made a change, using the Berton's billing address in Golden at about 5400 hundred feet, instead of their home's true elevation up in the mountains.
After a two-year battle, the couple says Xcel Energy is now paying them back $278 dollars in overcharges.
"This took the homeowners more than two years to get this resolved. Is that too long?" asked 7NEWS reporter Marc Stewart.
"It's too long. It's unfortunate that it took this long to resolve," said Xcel Energy spokesman Mark Stutz.
Xcel Energy confirms, as many as 500 mountain addresses may be getting a second look -- to see if the elevation levels are correct.
"Do you think had the homeowner not discovered this problem on their own, it would have ever been discovered by the utility?" asked Stewart.
"It is hard to say, given that, if their particular address came up during one of our more quarterly audits, it obviously might have discovered," said Stutz.
Diligent homeowners, whose careful eyes may help their neighbors bottom line.
"The fact that energy costs are so high already, and going up, it's just another reason to pay close attention to it," said Morris.
Stutz says it is possible the audit may reveal some homeowners were undercharged.
If you would like to review your bill with a representative or have questions, you can call Xcel Energy at 1-800-895-4999.