Age of Day & Night?

Anyone have any ideas about age of this Day & Night forced air gas furnace?

The home was built in 1975

Model #: 100D - 19
Serial #: CEGHG 45489

Has a standing pilot and ribbon burners.

I’m thinking it is original equipment but am looking for some validation.

Call Day/Night/Payne at 905 672-0860.

That serial number is not familiar.

Just a guess but I would say 1989. I don’t see many Payne and Day and Night furnaces.

The house was built in 1975–I doubt the furnace was replaced in 1989.

The Model #100D indicates to me this is an older furnace. If it is original
1975 sounds better to me than 1989. That’s why I suggested calling
BDP (Bryant-Day/Night-Payne) for clarification… and that is also why
the company publicizes that phone number.

I’m with you Jae (although I have to admit…like James…that I did think about 1989 for a little while).

I called the number you posted. But I got a recording of some store that said it was closed. Have you used this phone number before?


Looks like March 1974.

Thanks Russel.

Would you please inform us of the dating convention used on older Day & Night Furnace Serial Numbers.

Prestons gives me model #M-100D-19**C **

This unit has 100,000 BTU’s and was manufactured in 1973.

I also have an optional phone number…905-672-0606

This is one ancient furnace. If this oldie were on my inspection, this is what I’d be noting in my report…

The heating system was paced through it’s normal sequence of operating modes, with no obvious defects noted at time of inspection. However, due to systems age, it is clearly beyond it’s life expectancy, and replacement should be considered. Until then, I recommend annual maintenance and a heat exchanger evaluation from a licensed HVAC contractor.

They appear to be inconsistent in their use, but the first two letters are Month and Year.

A = Jan or 1970
B = Feb or 1971
C - Mar or 1972
D = Apr or 1973
E - May or 1974
F = Jun or 1975
G = Jul or 1976
H = Aug or 1977
I = Sep or 1978
J = Oct or 1979
K - Nov or 1980
L = Dec

Trying to use model numbers to determine manufacture dates will get one close, as will using the ANSI date. However, model numbers typically indicate the date that the model was introduced to the buying public, not when that specific unit was actually manufactured.

Thanks to everyone. Looks like I’ve got the validation I was looking for that this is the original furnace installed when the home was built in 1975.

I appreciate all the insights.

I dunno. I’ve had it in my files for 20 or more years. I need to do some updating, I guess.

No worries Jae… I had the same number in my file.

The alternate number that David Valley provided is to “Carrier Canada”. Carrier also manufactures Bryant, Payne, Day & Night as you indicated.

Ah…David’s number is now in my files and the other one ain’t.

Well, yes and no.

In 1945, Dresser Industries acquired Payne and Day & Night. Bryant was already a part of Dresser Industries. In 1949, Payne, Day & Night, and Bryant bought themselves out of Dresser Industries and formed Affiliated Gas Equipment (AGE). Carrier purchased AGE in 1955 and then formed the BDP Company in 1974 from Bryant, Day & Night, and Payne. United Technologies bought Carrier in 1979 and Payne separated from BDP in 1996 to form Payne Heating & Cooling but is still owned by Carrier. However, each company is its own company, doing its own research and manufacturing except as might be contracted with other companies. So Carrier doesn’t really “manufacture” Bryant, Payne, and Day & Night.

Sounds like you’ve done your research Russel. I stand corrected…

Guess I should have said “has had an affiliation with” instead of “manufacture”.

I have the same issue. I would like to know the age of my Day and Night Furnace.

Model #: 100CU - 12B
Serial #: 368-45535
Series 152

Any help would be appreciated.


I have the same issue. I would like to know the age of my Day and Night Furnace.

Model #: 100CU - 12B
Serial #: 368-45535
Series 152

Any help would be appreciated.


I believe that one is from March 1968, back when Day & Night was Day & Night, a major manufacturer and not just a brand name.

I agree, Prestons show that model as being current from 1968 to 1970, and the serial # suffix of 368 appears to be 3rd month of 1968.