Condensing Models: On-Demand Water Heater Service Handbook • 49
MAINTENANCE
10.3 Slide the outlet tube up and out
of the outlet water connec on.
Remove the tube.
10.4 Remove the three screws
at the top of the secondary
heat exchanger that are
securing it to the case. Refer
to Figure 51.
11. Separate the heat exchangers:
11.1 Li the heat exchangers out
of the cabinet.
11.2 Separate the primary and
secondary heat exchangers.
11.2.1 Remove fastener 14-22 (item
458, p. 70) from the tube
on the le -hand side. (This
tube connects the primary
heat exchanger to the
secondary heat exchanger.)
11.2.2 Remove the four screws that
connect the primary and
secondary heat exchangers
(Figure 50).
11.3 IF you are replacing the
primary heat exchanger
assembly, go to “Preparing
the New Primary Heat
Exchanger for Installa on
(Outdoor Models).”
IF you are replacing the
secondary heat exchanger
assembly, go to “Preparing
the New Secondary Heat
Exchanger for Installa on
(Outdoor Models).”
Preparing the
New PRIMARY
Heat Exchanger
for Installa on
(Outdoor Models)
The primary heat exchanger is the
same assembly for both indoor and
outdoor models. It comes with:
•
A combustion chamber attached to
the bottom of the heat exchanger.
See “Combustion Chamber,” page
70.
•
A plate attached at the top with
a gasket surrounding the flue gas
connection to the secondary heat
exchanger. See “Heat Exchanger
(Primary)” on page 70.
1. Make sure the gasket on top of
the primary heat exchanger is
not compromised. If it is, contact
technical support.
2. Remove the following items from
the primary heat exchanger and
INSTALL THEM IN THE SAME
LOCATIONS ON THE NEW HEAT
EXCHANGER:
•
High limit switch on the right
side (item 411, p. 70). See
also Figure 25 on page 36.
•
Over-heat Cutoff Fuse (OHCF)
(item 412, p. 70) and its five
clips. (Four clips are attached
to the primary heat exchanger
and one is attached to the outlet
tube.) See also Figure 25 on page
36.
•
Air tube and its connector/nipple
on the bottom of the combustion
chamber (Figure 52).
•
Two (2) freeze protection heaters
and clips; one is located on the
outlet tube near the bottom
and the other is located on
the connection tube from the
secondary heat exchanger. (See
items 413 and 414 on page 70.
See also Figure 47, page 47.)
•
O-Rings on the connection tubes:
Item 455 (p. 70) is attached
to the connection tube from the
secondary heat exchanger. Item
457 (p. 70) is attached where
the outlet water tube connects
to the outlet water connection.
(See connection points “A” and “C,”
p. 70).
CAUTION: These o-rings are
different sizes, so label them and
keep them separated.
Connector/
Nipple
Air Tube
Figure 52.
Three Screws Securing the
Secondary Heat Exchanger
Figure 51.
