North Star M157594I - Manual (Page 47)

Maintenance & Repair
47
Figure 18
Inspect heating coil
and desoot as
needed Inspect and desoot coil annually.
Most coils never require desooting. However, poor grades of fuel oil or
inadequate combustion air will cause heavy soot build-up on the outside
surface of the heating coil tubing. These deposits will insulate the coil,
which then restricts air flow through the heat exchanger and further
aggravates the soot build-up.
If soot has built up on the exterior of the coil tubing, clean as follows:
1) Wear protective clothing,
goggles, and gloves.
2) Disconnect high-pressure
hose on inlet side of coil
and thermostat on outlet
side of coil.
3) Remove the lid and
insulation lid from the
heating chamber and hoist
the coil out. Be careful, the
coil weighs 125 lbs.
4) Clean the coil.
5) Reassemble the coil and lids
to the machine. Make sure
the white insulation remains
in place.
6) Reattach high-pressure hose
and thermostat and make
sure all fittings are tight
before using the machine.
Outlet
Inlet
Figure 19
Lid
Insulation
lid
Heating
Coil
Heating
Chamber