Just bought a house in southern New Mexico. I am trying to find age information and a manual for the Friedrich 100,000 BTU gas furnace, model number GUA100NDB installed. Nothing appears on a Web search. I am getting that old sinking feeling about this unit's viability... ;>(

Is there any service records stuck to the machine? Or the name of the company that installed it?

Call them

Friedrich Heating & A/C York Heating Pitman, NJ (http://www.friedrichheating.com/furnace.asp)

No service records, just mfr. Info. Will locate and call NJ. Thanks to you both! I have a hunch this is going to be an 'adventure'... ;>)

Good luck