North Star M157305H - Manual (Page 17)

17
Cleaning Instructions for Flow Switch on 157306, 157307 & 157308
Mineral build-up and/or debris within the flow switch can occur and may affect burner operation if not
periodically cleaned. Mineral build-up and/or debris can stop the movement of the shuttle inside the flow
switch body. Shuttle movement is important because the burner will not fire if the shuttle does not move. The
shuttle movement actuates a switch inside the flow switch housing which allows the burner to fire during spray
mode.
Inspect and clean the flow switch as needed
1) Disconnect the swivel fitting from elbow to
the inlet of the coil
2) Disconnect the whole flow switch assembly
including the swivel and removable outlet
fitting where the brass body connects to
hose or tee depending on model
3) Unthread the removable outlet fitting with
the swivel still attached from the flow
switch assembly
4) Remove the shuttle
5) Clean the inside of the brass flow switch
body and the shuttle with water and a soft
brush
6) Insert the shuttle into the brass flow switch
in the orientation shown
Note: Aligning the male tabs on
the shuttle to the female guides
inside the brass flow switch body
can be difficult since the shuttle is
magnetic
7) Thread the removable outlet fitting with the
swivel still attached into the flow switch
assembly
8) Thread the brass flow switch body onto the
incoming water flow source (hose or tee)
depending on the model
9) Reconnect the swivel fitting to the inlet of
the coil
Removable
Outlet Fitting
Brass Body
Swivel
Fitting
Shuttle Alignment
Shuttle
male tabs
Shuttle
Swivel
Fitting
Removable
Outlet
Fitting
Flow Switch
Assembly
Brass Flow
Switch Body
female guides