PART 3
MAINTENANCE
3.1) GENERAL
Preventive Maintenance
"Preventive maintenance" is the best way to avoid
unnecessary expense and inconvenience. Have your
heating system and burner inspected at regular intervals
by a qualified service technician.
WARNING
Electrical shock hazard.
Turn OFF power to furnace before any disassembly
or servicing.
Failure to do so can result in bodily injury and/or
death, property damage.
A complete combustion test must be performed after each
annual service inspection of the unit, to maintain optimum
performance and reliability.
Do not tamper with the unit or controls. Call a qualified
service technician.
Before calling for service, check the following
a. Check oil tank gauge and check if the valve is open;
b. Check fuse or circuit breaker;
c.
Check if shut-off switch is “ON”;
d. Set thermostat above room temperature;
e. If ignition does not occur, turn off the disconnect switch
and call a qualified service technician.
When ordering replacement parts, specify the complete
furnace model and serial number.
3.1.1) Heat
exchanger
The entire heat exchanger should be inspected annually for
soot accumulation. If the burner is operating normally there
should be very little soot accumulation. If the heat exchanger
requires scale removal, use a wire brush first, to loosen the
scale and then vacuum the soot and scale that has fallen into
the secondary heat exchanger (radiator) section. You will find
that a 36" long flexible hose attachment will be helpful to reach
into the back of the radiator. A piece of 1/2" flexible gas
connector, or a piece of 1/2" liquid-tight vinyl jacket metallic
electrical conduit works well as a makeshift device.
Cleaning the heat exchanger
Remove the 4-bolt flange from the front of the furnace to
expose the clean-out port and check for soot deposits. If there
is very little soot in the radiator section visible from the clean-
out port, you will not need to clean it. However, if you notice
scaling in the radiator, you should remove it.
The wrap-around radiator can now be cleaned entirely from
the front inspection port. The furnace also has external clean-
out ports so the soot does not fall into the fan compartment
during the cleaning operation.
IMPORTANT
Do not vacuum the ceramic chambers—they are easily
damaged.
Soot will have collected in the first sections of the heat
exchangers only if the burner was started after the combustion
chamber was flooded with fuel oil, or if the burner has been
operating in a severely contaminated condition.
3.1.2) Refractory
firepot
Remove the burner and check the firepot.
IMPORTANT
This furnace has a fibre type refractory combustion
chamber. Normal servicing of this unit does not require
cleaning of the combustion chamber.
If cleaning of the pot should be required, use extreme
care. After firing, the pot becomes very fragile. Do not
use any commercially available soot removers.
If the pot is damaged, it must be replaced. A damaged pot
could lead to premature heat exchanger failure. Cracking of
the firepot is normal, however, replace the pot only if the
cracks have propagated more than 2/3 the way through the
wall thickness. The average wall thickness of the firepot is 19
mm (3/4").
Flooding of the firepot
Flooding can occur when the oil primary control has been
reset a number of times in a no-heat situation. Each time oil is
fired into the pot and does not ignite, it is absorbed into the
pot. Even if the burner is removed and the pot is felt for
wetness, it is difficult to assess the degree of oil absorption by
the pot.
There is only one way to properly service a flooded firepot,
and that is to replace it.
CAUTION
If you observe the red warning light on the burner, push
ONLY once to try and restart. If the burner does not
start, call a qualified service technician. Do NOT press
the button again.
Self-aligning firepot
The primary heat exchanger of the furnace is comprised of an
upper and lower half. The lower half is essentially a “can” that
contains a self-aligning firepot. The firepot fits into the bottom
half in one direction only.
20
Summary of Contents for NOLF105A12D
Page 25: ...DNS 0571 Rev C DNS 0573 Rev C FIGURE 5 1 Model OLR105A12D FIGURE 5 2 Model OLR160B20C 26...
Page 26: ...FIGURE 5 3 Model OUF105A12C FIGURE 5 4 Model OUF160B18C DNS 0572 Rev D DNS 0568 Rev C 27...
Page 27: ...FIGURE 5 5 Model OLF105A12C DNS 0570 Rev C FIGURE 5 6 Model NOUF105A12D DNS 0674 Rev E 28...
Page 28: ...FIGURE 5 7 Model NOLF105A12D DNS 0676 Rev D 29...
Page 30: ...COMPONENTS AND REPLACEMENT PARTS 31...
Page 31: ...PARTS LIST Model OLR105A12D B50031 B 32...
Page 33: ...PARTS LIST Model OLR160B20C B50032 C 34...
Page 35: ...PARTS LIST Model OUF105A12C B50033 B 36...
Page 37: ...PARTS LIST Model OUF160B18C B50034 D 38...
Page 39: ...PARTS LIST Model OLF105A12C B50035 B 40...
Page 41: ...PARTS LIST Model NOLF105A12D B50037 B 42...
