Teledyne Laars BR098906 Cupronickel Heat Exchanger, 18 Tube Assembly, 4500I (indoor), 4000E (outdoor), Previous Part #20098906
Used on the following models:
AP4000, AP4500, HH4000, HH4500, PH4000, PH4500, PW4000, PW4500, VW4000, VW4500,
MT4000, MT4500.