Intertherm Serial Number: How Old Is My Intertherm Furnace or AC?
In a Nordyne-family serial number, the two digits after the first three letters are the year and the next two are the month. Type the serial number below for the exact month and year.
About Intertherm
Intertherm is a Nordyne brand, very common in manufactured and mobile homes, and uses the Nordyne code.
Where to find the serial number
Furnace: Take off the front lower panel (turn the power off first). The data plate is a metal or foil sticker on the inside of the door or on the side of the cabinet, next to the blower. The serial number is usually labelled "Serial No.", "S/N" or "Ser. No."
Air conditioner: On the outdoor unit (the condenser), look for the data plate on the side panel, often near the electrical box where the power cables go in. The indoor coil or air handler has its own plate with a different serial number.
How to read a Intertherm serial number
In a Nordyne-family serial number, the two digits after the first three letters are the year and the next two are the month.
3 letters, then numbers
LLL YY MM #####
- Skip the 3 letters at the start.
- The next two digits are the year, then two digits for the month.
Example: GBB030708229
How long does a furnace last?
Most furnaces last 15 to 20 years. Yearly servicing, the local climate and how hard it works all move it within that range. Past 15 years, it is worth getting a replacement price before the unit fails, so you aren't forced into a rushed decision.
Questions
How do I tell how old my Intertherm furnace is?
Find the serial number on the data plate and read it with the Intertherm code: In a Nordyne-family serial number, the two digits after the first three letters are the year and the next two are the month. Or type it into the decoder on this page.
Is the manufacture date printed on the label?
Often, yes, especially on newer units and water heaters. Look for "Mfg. date", "MFD" or "Date of manufacture". If there is a printed date, it is more reliable than decoding the serial number.
Who makes Intertherm?
Intertherm is made by Nortek Global HVAC. The same serial code is used by Nordyne, Miller.
How sure are these dates? Based on a single published source. Treat the date as an estimate and check the label for a printed date. How we test the decoder.
Keeping an older furnace going
- Furnace air filter: Change it every 1 to 3 months. Check the size printed on the old filter.
- Carbon monoxide detector plug in: Any gas furnace, and especially an older one, should have a CO alarm nearby.
- Smart thermostat: Cuts run time on any system, old or new.