York International P2HMX12F08001, Installation Manual

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9
The Beckett burner bulk air band is
should be closed, and the air shutter
initial setting should be approximately
7.00.
Note A
: Locate hole at least 6 inches on
the furnace side of the draft control.
Note B
: Ideally, hole should be at least
12 inches from breeching or elbow.
PROCEDURE:
Start the burner and allow it to run at
least ten minutes. Set the air shutter to
give a good flame visually. The combus-
tion air supply to the burner is controlled
by manipulating the air shutter on the left
side of the burner, and, if necessary, the
bulk air band. To adjust, loosen the bolt
on the movable shutter. Move the shutter
gradually until a good flame (visually)
has been achieved. Re-snug the bolt.
Check the initial draft setting as the fur-
nace warms up. The draft may be meas-
ured at the test port. The breech draft
should be approximately - 0.05” w.c. to
obtain an over fire draft reading of - 0.02
inches w.c.
Fig. 6: Checking Over-Fire Draft.
Check the oil pump pressure. Standard
operating pressure is 100 PSIG.
After reaching steady state, take a
smoke test. If not indicating a trace, set
the combustion air controls to provide a
trace.
Typically, the CO
2
reading will range
from 11.5% to 13.5%.
After the air adjustments have been
completed, and the air shutter or air ad-
justment plate has been secured, re-
check the over fire draft and take another
smoke test to ensure that the values
have not changed.
SMOKE TEST NOTE
:
If oily or yellow smoke spots are found
on the smoke test filter paper, it is usu-
ally a sign of unburned fuel. This indi-
cates poor combustion. This type of
problem may be caused by excess draft,
excess air, or contaminated fuel. Do not
ignore this indicator.
STACK TEMPERATURE:
Stack temperature will vary depending
on fuel input, circulating air blower
speed, and burner set up, etc. In gen-
eral, stack temperature should typically
range between 380°F to 550°F, assum-
ing that the combustion air is approxi-
mately room temperature (65°F - 70°F).
In general, lower stack temperature indi-
cates greater efficiency; however, ex-
cessively low stack temperature can lead
to condensation forming in the chimney
and / or venting. Sulphur and similar
contaminants in the fuel oil will mix with
condensation to form acids. Acids and
resultant chemical salts will cause rapid
deterioration of the chimney and venting
components, and may attack the fur-
nace.
If the flue gases are below the range, it
may be necessary to slow down the
blower fan. If the flue gases are above
the range, the blower fan may require
speeding up. Stack temperature varies
directly with the system temperature rise.
System temperature rise is the difference
between the furnace outlet temperature
and furnace inlet temperature as meas-
ured in the vicinity of the connection be-
tween the plenum take-offs and the trunk
ducts. Typical temperature rise values
range between 55°F and 85°F.
If the venting from the furnace to the
chimney is long, or exposed to cold am-
bient temperatures, it may be necessary
to use L-Vent as the vent connector to
reduce stack temperature loss to prevent
condensation. The venting should be
inspected annually to ensure that it is
intact.
FURNACE INSTALLATION
SET-UP
The furnace must be set up as the final
step in the installation.
A) The oil burner must be set up follow-
ing the procedures outlined above.
B) The P2HMX1208001 and
P3LBX12F08001 models should operate
within a temperature rise of 60°F to 90°F.
The P3HMX14F10001,
P3HMX20F12001 and P3LBX14F12001
models should operate within a tempera-
ture rise of 55°F to 85°F. To determine
the temperature rise, measure the supply
air and return air temperatures when the
furnace has reached steady state condi-
tions. This is the point at which the sup-
ply air temperature stops increasing rela-
tive to the return air temperature. The
furnace may have to run 10 to 15 min-
utes to reach steady state conditions.
The measurements may be made with
duct thermometers or thermocouples
used in conjunction with multi-meters
with temperature measurement capabili-
ties.
The return air should be measured at a
point where the thermometer will be well
within the air stream near the furnace
return air inlet. Actual location is not par-
ticularly critical; however, avoid locations
where the temperature readings could be
affected by humidifier bypass ducts, the
inside radius of elbows, etc.
The supply air temperature should be
measured at a point where the ther-
mometer will be well within the air stream
near the furnace supply air outlet. Usu-
ally, the side mid-point of the supply air
plenum take-off is ideal, providing it is
out of the line of sight to the heat ex-
changer. If the thermometer is within the
line of sight of the heat exchanger, the
supply air readings may be skewed by
radiant heat from the heat exchanger. If
the plenum take-off is unsuitable, the
supply air temperature may be measured
within the first 18 inches of the first seg-
ment of supply air trunk duct.
If the temperature rise is outside the rec-
ommended range, it may be adjusted on
direct drive equipped units by selecting
alternate circulation fan motor speeds. If
the temperature rise is too high, speed
the fan up. If the temperature rise is too
low, slow the fan down.
C) Keep in mind that the stack tem-
perature varies directly with the tempera-
ture rise. The higher the temperature
rise, the higher the stack temperature will
be, resulting in lower efficiency. The
lower the temperature rise, the lower the
stack temperature will be, which, in some
cases, may allow condensation to form
in the chimney and other vent parts.
D) Test the high limit control to ensure
that it is operating correctly. This may be
done by temporarily removing the circu-
lator fan heating wire or neutral wire.
Turn of electrical power to the furnace
before working with the motor wires. Be
sure to protect any removed wires from
shorting out on metal furnace parts. If the