LAARS FT Wall and Floor Models -LOW LEVEL SENSOR ASSEMBLY (LWCO) -Generation 1 and Generation 2.
The Low Level Sensor Assembly for a Generation 1 Boiler Wall and Floor and Combi Wall and Floor is a LAARS Part # FT 1325. This sensor assembly is a "threaded , screw in" connection.
The Low Level Sensor Assembly for a Generation 2 Boiler Wall and Floor and Combi Wall and Floor is a LAARS Part # FT 3314. This sensor is a "slide in with a fastening/retaining clip" connection.
Obviously, these Sensor Assemblies are NOT backwards and forward compatible due to their very different installation connections .
A "Generation 1" wall boiler and combi is easily differentiated from a "Generation 2" by a few factors:
1) The front cover (Generation 2 more defined).
2) The addition of the left side access panel (Generation 2 Wall).
3) The addition of the intake air screen (Generation 2).
4 The physical location of the pressure gauge . Generation 1 on the bottom of the boiler cabinet, Generation 2 thru the front cover.
5) The heat exchanger insulation more abundant and thicker on Generation 2.
* I have purposely excluded serial #'s from this short list due to inconsistency in information regarding serial #'s and upgrades.