• Each Hvac brand has its own serial and model number and each serial and model number have a different way of telling you the information. You can’t use Carrier serial and model to decode Trane hvac units. It would be confusing and wrong. Some hvac brand also has new code for its new hvac units. For example, York hvac had two different serial.
• So the “M3004” in the serial number below means it was manufactured in the 30th week of 2004, and the “MFD. 07/04” confirms it. For the age of another brand or manufacturer, go to our blog post How do I determine the age of my air conditioner? To find the size of your Ruud system, go to How many tons is my Ruud air conditioner or heat pump?

1. Ruud Heat Pump Model Numbers
2. Ruud Furnace Model Numbers

Prestons will give you good data on units prior to 2005. Worth the cost if you work in the replacement market. I wouldn't worry as much about replacement windows changing the loads as I would the potential to improve performance by fixing the duct system. Correct sizing, correct construction, and sealing. If you are investing 6-15K for a new HVAC unit - another 1-3K for an effective distribution system is very reasonable. It will do more for comfort than a round of replacement windows that cost more.

Ruud. RUG PRO40-40F 40 40 N 3 68 0.62 21 63 1/4 8-Year 8-Year Rheem 41XR40 40 40 N 3 68 0.62 21 61 3/4 10-Year 1-Year Ruud MHR40 40 40 N 3 68 0.62 21 61 3/4 10-Year 1-Year AWHC. FG122-40T40-3NOMV 40 40 N1 3 69 0.63 20 62 12-Year 12-Year N1 Propane, change 'N' to 'P' in model number. AWHC models with prefix 'FG' will change to prefix 'BFG' 2006.

Determining water heater age date from serial numbers by Final Analysis Home Inspections in Virginia beach, Chesapeake, Suffolk, and Portsmouth Virginia, Va..

What Are Rheem AC Model Numbers For? Rheem air conditioning model and serial numbers are used to determine the age of the unit as well as where it was made. This information is used for insurance issues, when signing up for service contracts and for finding replacement parts. SERIAL NUMBER NOMENCLATURE Prior to 1980 April 1, 1980 to June 1,1980 June 1, 1980 to Current 123456 A D 123 D A 123456 123 H 02 Compressor Part Number 123= 8000- 123 Date Code Unit Identity1962=B Number MONTH JAN = A FEB = B MAR= C APR = D 1972=M.

Determining water heater age.

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Related article: Also see 'How big should your water heater be' at our Home Inspection news blog.

As home inspectors it's important to be able to decipher the age from the water heater manufacturers serial numbers so we can report aging conditions and tell you when you can expect to replace them because a water heaters service life is approximately 13-18 years.

All water heaters have a Rating Plate that lists important data such as the model and serial numbers, manufacturing company's name, length of warranty, wattage of elements installed (on electric models), gallon capacity, input BTU rating (gas models), and more.

You can determine the age of the water heater by de-coding the serial number. Some manufacturers make it easy by incorporating the month and year built into the first 4 digits of the serial number. For instance, the picture below shows that this Rheem water heater was manufactured in December of 1991 (1291). Other manufacturers use different formats, but in a similar fashion.

Let's decode the above rating plate: This is a model 21V50-2, serial number 1291A39968, manufactured in December of 1991, 50 gallons, 36000 BTU's per hour, and it set to work with Natural Gas only. The other info you see relates more to Service Technicians, and shouldn't be needed by the average homeowner.

Ruud Heat Pump Model Numbers

The picture below shows the entire Rheem Rating plate. This 50 gallon electric tank was built in August of 1984, and came equipped with 4000 watt elements

AO SMITH rating plates look a little different, but have all the same info. Their date de-coding is a little different.

AO SMITH puts the year first (1991), and the month second (07, or JULY). It's a little harder to find the info on the AO SMITH plate, but it's all there!

American water heater rating plate, with close up below.

American's format puts the year first, then the week the tank was built. In this example, the tank was made in the 17th week of 1998.

The Bradford White rating plate is the most difficult to decode. To find the age of a Bradford White tank, you have to understand their coding. The year of manufacture is noted by the first letter of the serial number, the month is the second letter. The decoding is based on the following format:
Year Decoder: G = 1990; H = 1991; J = 1992; K = 1993; L= 1994; M= 1995; N= 1996; P= 1997; S= 1998; T= 1999; W= 2000; X= 2001; Y= 2002; Z=2003; A= 2004; B=2005; C=2006; D=2007
Month Decoder: A= JAN; B=FEB; C=MAR; D= APR; E=MAY; F= JUNE; G=JULY; H= AUG; J= SEPT; K=OCT; L= NOV; M= DEC.

The example rating plates is on a tank made in June 2002.

Below is a close up of the Bradford White rating plate. This is a 40 gallon electric water heater, model number MI40L6DS13, manufactured in June of 2002. It comes equipped with 4000 watt elements. Note the 'Maximum Watts' at 4000, this means this tank was built to operate in the 'Non-simultaneous' mode, meaning only one element will energize at a time (standard for residential water heaters). It is designed to operate with a maximum of 150 PSI water pressure, but was tested to 300 PSI at the factory for your safety (a Federal Standard!).

Ruud Furnace Model Numbers

Carrier Furnace Model Numbers

Water Heater serial number chart Back to Tech Library

Manufacturer	Trade name	Where to look	How to decode	Example
American	ACE, American, American Hardware, America's Best, Apex, Aqua Temp, AquaTherm, Aquamatic, Best, Best Deluxe, Champion, Craftmaster, De-Limer, Deluxe, Eagle, The Earl's Energy Conservation Water Heater, The Earl's Energy Saver Plus, Envirotemp, Four Most, Hotmaster, Hotstream, King-Kleen, King-Line, Master Plumber, Nationaline, Neptune, Penquin, Premier Plus, Premier Plus Self Cleaning Prestige, ProLine and ProLine Plus, Quaker, Quick-Flo, Raywall, Revere, Riveria, Sands, Sentinal, Servi-Star, Shamrock, Special Deluxe, Standard, Super Eagle, Super-Flo, Supreme, Sure-Fire, Thoro-Clean, Tru-Test, Tru Value, U.S. Supply, Whirlpool, XCL Energy Saver	Serial # – 1st 4 digits	Serial # – 1st 4 digits	8906xxx = made in the 6th week of the year 1989
A.O. Smith Water Products	National, A.O. Smith, Glascote, Perma-Glas	Serial # – 2nd, 3rd, 4th characters	2nd position (letter) = month (A being January through M being December) 3rd & 4th position (numbers) = year	AJ89xxx = made in October (J) of 1989
Apollo Comfort Products	See State Industries
Bradford-White	Bradford White, JetGlas	Serial # – 1st 2 letters	1st letter = year starting with A as 1984, 2nd letter = month with January (A) through December (M)	JMxxx = made in the year 1992 (J) in the month of December (M)
Crispaire	E-tech
GSW Water Heating	John Wood, GSW, Moffat, Superflue, Medal	Serial # – 1st 4 digits	1st & 2nd number = year, 3rd & 4th number = month	8901xxx = made in the year 1989 in the first month, January
Heat Transfer Products	Heat Transfer
Lochinvar	Energy Saver, Golden Knight, Knight
Marathon	Marathon	Serial # – 1st 4 digits	1st & 2nd digit = month, 3rd & 4th digit = year	0189xxx = made in the year 1989 in the first month, January
Maytag	Maytag
Rheem	Aqua Therm, General Electric, Hotpoint, Professional, Rheem, Vanguard, Western Auto	Serial # – 1st 4 digits	1st & 2nd digit = month, 3rd & 4th digit = year	0189xxx = made in the year 1989 in the first month, January
Richmond	Serial # – 1st 4 digits	1st & 2nd digit = month, 3rd & 4th digit = year	0189xxx = made in the year 1989 in the first month, January
Ruud	Professional, Ruud	Serial # – 1st 4 digits	1st & 2nd digit = month, 3rd & 4th digit = year	0189xxx = made in the year 1989 in the first month, January
Sears, Roebuck and Co.	Kenmore
State Industries	State	Serial # – 1st 3 characters	first letter = month (A being January through M, being December), 2nd and 3rd position (numbers) = year	J89xxx = made in October of 1989
Summit Manufacturing Mortex	Sun Therm
U.S. Craftsmaster	Ace, American Hardware, America's Best, Apex, Aqua Temp, Aqua Therm, Aquamatic, Best, Best Deluxe, Craftmaster, De-Limer, Deluxe, Eagle, The Earl's Energy Conservation Water Heater, The Earl's Energy Saver Plus, Envirotemp, Four Most, Hotmaster, Hotstream, King-Kleen, King-Line, Master Plumber, Nationaline, Neptune, Penquin, Prestige, Pro-Line, Pro-Line Plus, Quaker, Quick-Flo, Raywall, Revere, Riviera, Sands, Sentinal, Servistar, Shamrock, Special Deluxe, Standard, Supereagle, Super-Flo, Supreme, Sure-Fire, Thoro-Clean, True-Test, Tru Value, U.S. Craftmaster, U.S. Supply, Whirlpool, XCL Energy Saver	Serial # – 1st 4 digits	1st 2 digits = year 2nd 2 digits= week	8924xxx = made in the 24th week of the year 1989
Vaugn Manufacturing Corp.	Sepco, Hydrohot, D.W. Whitehead

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