Install Instructions

Part number 550-100-055/0618
5
gas-fired water boilers — Heat Exchanger Block Replacement Instructions
5. Remove the (4) Phillips head screws from the top rear
plastic panel.
6. Remove and discard flue sensor and grommet from
stainless vent pipe inside boiler, see Figure 3.
Figure 2 Front top removal
Label wires before removing
Label all wires prior to disconnection when ser-
vicing controls. Wiring errors can cause improper
and dangerous operation.
7. Loosen the PVC band clamp at the vent and intake
adapters using a 5/16” nut driver.
8. If possible remove the PVC vent and intake pipes from the
adapter. If not enough free movement of the vent and intake
Figure 3 Flue sensor removal
pipes, cut either or both the PVC intake and vent pipes above
the top of the vent and intake adapters for adequate clearance.
Figure 4 Flue pipe cut off for removal
PVC air pipe must be supported. Failure to do so
could result in damage to the air pipe system.
9. Remove the (5) screws with a 5/16” nut driver from the intake
and the vent adapter by moving the top plastic cover to gain
access to the screws, see Figure 5.
10. Remove and discard the intake adapter by breaking it loose
from the top panel gasket. Remove and discard the vent
adapter by pulling straight up on the vent adapter while
rocking it side to side to remove the adapter from the flue
outlet of the heat exchanger.
Figure 5 Flue clamp loosened for flue pipe removal