I have a Tempstar Furnace Model # NUGK125DK03 / 867.769442 I am trying to find out the age of this furnace. It says it is High Efficient. Can someone please tell me the approx date of manufacture or a location where I can get this info. Thanks.

Post the serial number of the unit ( listed on the ID tag... ) should start with an L this will be the date it ran off the assembly line.

Serial number for this Tempstar is: L884576308

Your unit was made in 1988 the 45 week of that year it was manufactured, ( off the assembly line )... then it is usually in stock in Tenn. For up to a year... as wholesale companies put in their order from the ICP wharehouse... and depending on their stock rotation / sales it may move out slowly from some wholesale houses... and worst case, they don't rotate their stock... it could be two years old from mfg date when it is installed. BUT the warranty starts on the day they install it...

Thanks for the info. At least I know the main unit is around 20 years of age. Based on part numbers though it seems a lot of updates have been made. Only thing I have replaced in the last 5 years is the Cam-Stat limit/fan control.

The cam-stat failure was a very commen problem with that series of furnaces... as long as they are set up properly... they can have a long life...

Have your heat exchangers checked, very commonly the secondary is cracked on that model.

Thanks for that recommendation. They were changed about 5 years ago so should be still OK.

I have a Tempstar High Efficiency Sp 80 the only numbers I could find were ST9120G 2008 and HQ10008773HW and finally LR91984 I think I need a new furnace but have no idea how old this one is. My husband died and I don't remember those things. Can you help. I have to keep my temp at 50 degrees because of being on a fixed income. Please help

Hi! Could you please help me out- trying to find out the year of my furnace... serial # 4044933. Many thanks!!