Millions of Americans have a home warranty, paying on average $500 a year for peace of mind in case a major appliance stops working.

But thousands of them have filed complaints with the Better Business Bureau, claiming their warranty refused to pay when they needed it most.

Rosalie Battle is one of them. When her 16-year-old heat and air conditioning stopped working, she called her home warranty company.

She had been paying them $50 a month, more than $500 dollars a year for protection.

So they sent a repairman, who claimed it was a simple fix.

"He said it was a fuse," Battle said. But it wasn't. "Two hours later it went out again," she said.

So she called again, and the warranty company sent a second repairman, who this time diagnosed a blown heat exchanger. But she was stunned by what the warranty company then told her.

"They told me they are not going to fix it because it's a manufacturer's defect. I said what's that got to do with me? I just need it fixed," she said.

The warranty company, however, told her the $1,000 repair did not qualify for coverage.

Thousands of complaints over repairs denied

Sarah Wetzel of the Better Business Bureau says consumers need to take caution if a warranty company says that everything is covered, because many have dozens of exclusions.

She says warranties can be a great deal if they actually cover the costs. But the Bureau has thousands of complaints concerning dozens of warranty companies.

To protect yourself, Wetzel says:

Rosalie Battle ended up canceling her home warranty, saying it was not worth over $500 a year, if it would not cover a furnace and AC repair.

So do your homework first, so you don’t waste your money.

Don't Waste Your Money" is a registered trademark of Scripps Media, Inc. ("Scripps").

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