Low Draft Voltage Adjustment - Harman PELLET P61A Installation & Operating Manual

Fig.22

low draft voltage Adjustment

These units are pre-tested at the factory with
exactly 120 Volts A.C., 60 Hz. They are checked
and adjusted for firebox tightness, gasket leakage,
motor operation and igniter operation. The P61A is
then factory set at a mid-point adjustment and in
most cases will not need any adjustments. nOte:
the factory low draft setting may not be correct
for the unit's permanent installation conditions.
The control board on the P61A is equipped
with a low draft adjustment port. Located on the
control face just to the right of the igniter light. This
voltage adjustment is provided to allow the unit to
be adjusted for the household voltage where the
unit is going to be in permanent operation. nOte:
the line voltage varies from area to area and
often home to home.
The low draft voltage should be adjusted to
achieve the most efficient burn on low burn or
"maintenance". This voltage adjustment allows
the installer to change the low voltage set point
approximately 10 volts. This adjustment should be
done by the installer during set up because a draft
meter reading is required to insure proper set up.
If the unit is not adjusted properly, it does not
cause a safety concern. If the unit is adjusted too
high, only efficiency is lost. If the unit is adjusted
too low, the low draft pressure switch will not allow
low draft voltage Adjustment
C o m b u s t i o n
M o t o r S p e e d
Control
Low draft only
set point.
The small straight
screwdriver slot is
plastic; therefore,
the unit can be
adjusted while in
operation.
Draft Meter bolt
hole location
The draft test hole
is under the left rear
corner of the firebox.
the feed motor or the igniter to operate.
A simple draft test should be performed after
completing the flue pipe installation. To record the
results for future reference:
1. Plug unit into a 120VAC, 60 HZ outlet.
2. Close the hopper lid, front view door, and the
ash pan. Neither pellets or a fire are required for
this test.
3. With the mode selector in the "OFF" position,
turn the feed adjuster to "TEST".
4. Record the high draft_____in W.C. (Normal is
-.50 to -.60) The control will be on the High Draft
for a total of 1 minute.
5. After the minute, the combustion motor will go
down to low draft and the distribution blower will go
on high. Allow approximately 15 seconds to pass
for the combustion motor to slow before checking
the low draft.
6. If the low draft is between -.35 and -.45, record
the reading _____ in W.C. If the reading is higher,
slowly turn the set screw counter-clockwise until the
draft lowers. If the reading is lower, very slowly turn
the set screw clockwise until the draft increases.
nOte: in some cases, the draft may not go
as low as -.35 to -.45 even with the set screw
completely counter-clockwise. ideally, you
should just set it as low as possible.
Fig. 23
P61A Pellet Stove
20