Dettson ODH53-F, Инструкция по эксплуатации

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4- MAINTENANCE
4.1- 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.
After inspection, a complete combustion test must be performed after
each annual service 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:
1. Check oil tank gauge and check if the oil tank valve is open;
2. Check fuse or circuit breaker;
3. Check if shut-
off switch is “ON”;
4. Reset thermostat above room temperature;
5. 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 number and serial number.
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.
4.2- INSPECTION POINTS
4.2.1- 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 0.9m (36”) long flexible hose attachment will
be helpful to reach into the back of the radiator; a piece of 12.7 mm (1/2”)
fle
xible gas connector, or a piece of 12.7 mm (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
the scale.
The wrap-around radiator can now be cleaned entirely from the front
inspection port. Also, the furnace 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.
4.2.2- Refractory fire pot
Remove the burner and check the fire pot.
IMPORTANT
Use extreme care if cleaning of the pot is required. After
firing, the pot becomes very fragile. Do not use any
commercially available soot remover. This furnace has a
fibre type refractory combustion chamber. Normal
servicing of this unit does not require cleaning of the
combustion chamber.
If the pot is damaged, it must be replaced. A damaged pot could lead to
premature heat exchanger failure. Cracking of the fire pot 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 fire pot
is 19.1 mm (3/4”).
Flooding of the fire pot
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 fire pot, and that is
to change it.
CAUTION
If you observe the red warning light on the burner, push
ONLY once to try and restart. If the burner will not start,
call a qualified service technician. Do NOT press the
button again.
Self-aligning fire pot
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 fire pot. The fire pot fits into the bottom half in one direction only.
Removing the fire pot
The fire pot is seldom replaced, but when it has to be replaced one must
simply:
1. Remove the burner;
2. Remove the burner Limit Control;
3. Remove the breach plate;
4. Remove the front panel;
5. Remove the brass nuts on the stainless steel heat exchanger
studs;
6. Pry the bottom half of the heat exchanger apart by using the
designated prying tabs;
7. Remove the bottom half of the heat exchanger through the front of
the furnace;
8. Pull the fire pot up and out of the bottom half of the heat exchanger;
9. Remove the old sealing gasket from the flange of the upper half of
the heat exchanger;
10. Scrape any residual gasket material off the matching flanges of the
heat exchanger.