How old is my Bryant furnace or AC?

By Dana Whitlock. Updated October 2026. Widely documented.

Bryant follows Carrier's habit of putting the week first. Take the first four characters of the serial and read them as week, then year. 3709E07806 was built in week 37 of 2009, mid-September. 0709G10932 is week 7 of 2009, mid-February.

Bryant has not published the rule under its own name, so it carries the Widely documented label here. It is the same rule found in Carrier's service manuals, and inspectors and distributors read Bryant plates the same way. For units from 2020 on, no dated label has confirmed it yet. Treat those results as a strong estimate.

Where to find the label on a Bryant furnace

Walk around the outdoor condenser or heat pump: the rating plate is fastened to one side of the cabinet, often near where the refrigerant lines enter. For a Bryant furnace, it is inside the door. First set the thermostat to off and shut the service switch next to the furnace. Then lift off the door and read the label with a flashlight. Do not stick your hands or a phone into the cabinet while the furnace is running, and leave any panel that needs a screwdriver to a licensed HVAC technician. A photo you can zoom into is easier to read than squinting at faded print.

How to read the code

Bryant's current serials run ten characters. The opening pair is the week (01 to 53). The second pair is the year, where 85 through 99 belong to the 1900s and 00 onward belong to the 2000s. Character five is a letter for the factory. The final five digits are the unit's place in production. A quick week-to-month table: weeks 1 to 4 are January, 14 to 17 are April, 27 to 30 are July, 40 to 43 are October, and 49 onward are December. Week 37 is therefore September.

Real serials in this code

When the format changed

Bryant has used this week-first layout since roughly the mid-1980s, the same era Carrier adopted it. Older Bryant serials in other layouts exist, and this site does not decode them because sources disagree. The 2020s are the open question. The rule has not changed as far as anyone has documented, but no Bryant or Carrier unit built in 2020 or later has turned up with a printed date to prove it. If the year matters for a warranty claim or a home sale, use Bryant's warranty lookup with the full serial, or check the date on your installation invoice or permit.

Who makes Bryant

Bryant is built by Carrier, and Bryant's own website carries the line 'A Carrier Company'. Carrier, Bryant and Payne (now sold as WeatherMaker by Carrier) all share the week-then-year serial pattern, so you can decode any of the three the same way. Bryant equipment is sold through its own network of independent dealers.

How sure is this?

Widely documented. Bryant doesn't publish this code; it comes from recall notices, service literature and inspector references. We tested the carrier rules against 17 serials, 7 of them with a date known from a recall notice, a printed label date or the maker. None decoded to a wrong year; codes whose year mark repeats show every possible reading. Always confirm with Bryant's serial lookup before you spend money on the answer.

Quick notes

• A Bryant serial that starts 37 means week 37. There is no 37th month.
• If the year pair reads 27 to 84, you have copied something wrong: those years cannot exist yet in this format.
• Compare your furnace and condenser serials. Matching years usually mean the whole system went in at once.
• When the condenser plate has faded past reading, date the Bryant furnace and use the install invoice to confirm the outdoor unit.