Harman Stove Company PB 105 Installation & Operating Manual page 31

Latch (2) Latch (2) Latch (2)
Thumb Screws (3 Total) Thumb Screws (3 Total)
Sealing Overlap Sealing Overlap
5" Double 5" Double
Bladed Fan Bladed Fan
Combustion Blower Cleaning
Remove the combustion blower heat shield.There
are two latches that hold the shield in place . See Fig. 22
Flip the latches up and pull the shield away from the furnace.
It can not be fully removed, it can only be moved down over
the wire until it hangs on the junction box.
Maintenance
Heat Shield Heat Shield Heat Shield
Fig. 22
ESP Probe
Combustion Combustion
Blower Motor Blower Motor
Fig. 23
Fig. 24
The furnace MUST be OFF and COOL before you
should attempt to clean the combustion blower.
The wire to the combustion blower doesn't need to be
disconnected during the cleaning process.
Loosen the three (3) thumb screws about 4 turns each.
See Fig. 23. Hold the motor head with one hand and the blower
plate handle with the other hand. Pull outward on the plate
handle until the complete unit comes loose. Now rotate the
plate counter-clockwise about 1/8 turn. This will allow the
complete assembly to be removed from the blower chamber.
Clean the blower fan blades and the blower plate
sealing overlap. See Fig. 24.
NOTE: Be carefull not to bend the fan blades, this
will throw the fan blade out of balance or it may rub the
inner chamber, which may affect the performance of the
boiler. Any horizontal and vertical flue pipe directly above
the unit should be cleaned at this time
NOTE: The horizontal flue pipe directly above the
boiler is the first place fly ash will settle, due to the slow-
ing of flue gas velocity through horizontal pipe. Cleaning
of horizontal venting pipes is very important to the effi-
ciency of this boiler.
Clean the flue outlet throat as well as the inner chamber
of the flue tunnel (this is the hole that goes up into the flue
pipe). See Fig. 24.
NOTE: The ESP probe sensing tip extends into this
same area. CARE MUST BE TAKEN NOT TO DAM-
AGE THE ESP PROBE DURING CLEANING. Bending
of the ESP probe will make it difficult to remove if it should
become necessary. See Fig. 24.
Clean the boiler blower plate, sealing overlap. See Fig
24. Make sure there are no fly ash buildups that may block
the easy flow of flue gasses into the combustion blower inlet
hole. ( A flashlight may be necessary. )
Cleaning the Tube heat Exchangers:
The heat exchanger tubes have external handles that
operate the cleaning mechanisms. See picture on page 29.
This cleaning should be done at least once a week, al-
though it can be done as often as desired. The cleaner the
heat exchangers are, the more efficient the boiler will be.
This cleaning can be done at any time and in any mode of
operation.
CAUTION: Inspect flue pipes, flue pipe joints and
flue pipe seals regularly to ensure that smoke and
flue gases are not entering the home.
31