Lennox Size & Age help

Hi, I looked all over for this info. apparently the age was on the unit elsewhere (at some time).
Lennox Model # HS9-652-1P
Serial # 51
There is some numbers at the bottom of the data plate with no ID they are 8-6-843601.
If I can’t age it, can you help me size it?? Thanks in advance for your help.Robert

According to a ARI book (the HS9 lived from 1976 to 1981)
Is that about right for the age of the house?

4-1/2 ton I think but the 652 doesn’t track in my information.

Wait for someone else to come along and confirm.

Should be a date tag on the Lennox.

Hi to all,

Prestons list the HS9 upto 1984, and that appears to be confirmed in the serial #



Gerry, would you also say it was a 4.5 ton unit? Thanks again, Robert