Noritz N-0841MC Series Manual page 7

Procedure
8. Remove heat exchanger from case
(1) Remove the 2 set screws on the
bottom of the burner
(2) Remove the upper left and right set
screws near the top center of the case
(support bottom of assembly)
(3) SS HE, CU HE, Burner, and Fan will
come out in one section. Remove
from unit.
9. Separate the SS HE from CU HE
(1) Remove the 2 screw on the bracket
between the SS HE and CU HE
(2) Flip the Assembly over and locate the
foam covered pipe connecting the two
heat exchangers
Diagram
Page 7