New Gas Furnace

Had a phone call from a lady who sated that her furnace which was installed 3 weeks ago, has a burning odour coming from it. She had the installers out 3 times, they could not smell anything and could not find anything wrong. She insisted that her and her friends can still smell burning oil.
They had their old oil furnace replaced by a propane furnace. I asked if they cleaned the duct work but she said no. The furnace has been running for three weeks now so they feel that any film on the new system should have burned off by now.
Any one have any thought as to what could cause the smell and is there any method of testing the fumes that is apparently is coming from the furnace?

Why does she not call the supplier ,He sould be there in a heart beat ,A happy customer leads to more sales .

Douglas has anybody gone in with a VOC tester? I have found in my career that HVAC contractors cannot smell the fumes and therefore say there is nothing wrong. It could be anything and the only way to trace out the problem is to call someone that has sensitive enough equipment to find the problem. New furnaces do have small cracks in the exchanger that will not be detected by CO they also have small leaks at fittings and only can be found with soaping the joints or a sniffer.

Roy: apparently the installer has gone back three times but has not found anything wrong.

Kevin:
I’ll give her a call on Monday and ask her what the installer did to check for leaks.

Now call the Manufacturer… not the installer.