York P3DHX12F08001 Manuale Utente

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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 breech 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 70°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 furnace should operate within a 
temperature rise of 85°F ±15°F. To de-
termine the temperature rise, measure 
the supply air and return air tempera-
tures when the furnace has reached 
steady state conditions. This is the point 
at which the supply air temperature stops 
increasing relative to the return air tem-
perature. The furnace may have to run 
10 to 15 minutes to reach steady state 
conditions. The measurements may be 
made with duct thermometers or thermo-
couples used in conjunction with multi-
meters with temperature measurement 
capabilities.  
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, 
on belt drive equipped units by adjusting 
the variable speed motor pulley. 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. For direct 
drive equipped units, this may be done 
by temporarily removing the circulator 
fan heating wire or neutral wire. For belt 
drive equipped units, temporarily remove 
the fan belt. Turn of electrical power to 
the furnace before working with the mo-
tor wires or fan belt. Be sure to protect 
any removed wires from shorting out on 
metal furnace parts. If the high limit test 
is successful, shut off the electrical 
power to the furnace, restore the proper 
motor wiring. Finally, restore power to 
the furnace. 
E)  Adjust the “Fan Off” setting on the 
L6064A or L4064W fan limit controller. In 
most cases, the “Fan Off” temperature 
should be 90° to 100°F as indicated on 
the thermometer used to measure the 
supply air temperature. Once the “Fan 
Off” setting has been established, set the 
“Fan On” setting. In most cases, the “Fan 
On” setting should be approximately 
30°F higher than the Fan Off” setting. 
NOTE: The L4064W fan/limit controller 
has an auxiliary “fan on” function that 
activates when the thermostat is calling 
for heat. The controller is designed to 
start the circulating fan in 20 to 30 sec-
onds. Adjust the “fan on” setting on the 
controller dial 30°F higher than the “fan 
off” setting even though the circulating 
fan will normally be started by the auxil-
iary “fan on” function. 
F) Operate the furnace through a 
minimum of three full heating cycles. 
During this time, check for fuel oil leaks, 
gross air leakage from the supply air 
ductwork, unusual noises originating 
anywhere within the heating system 
which may cause some concern or an-
noyance to the home owner, etc.  
G) Be sure that the homeowner is 
familiar with the furnace. The 
homeowner should be aware of the 
location of electrical circuit breaker or 
fuse, the location of any electrical 
switches controlling the furnace, the 
location of the oil tank shut-off valve and 
how to operate the valve. The home-
owner should be informed where the oil 
tank gauge is located and how to read it. 
It would be beneficial to review safety 
issues with the home owner, such as the 
danger of storing combustibles too close 
to the furnace, hanging anything on the 
furnace vent pipe, and especially the 
dangers of indiscriminately pressing the 
burner reset button.