elco N6.2400 G-R, Руководство по эксплуатации

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10/2010 - Art. Nr. 4200 1030 6900A 23
Servicing
Exhaust gas test
Trouble shooting instructions
Exhaust gas loss
Exhaust gas loss by way of free heat will
occur as a result of the temperature
difference between the fuel-air mixture
entering the furnace chamber and the
gases discharged. Any increase in the
excess of air and the resultant higher
exhaust gas volume will cause the
exhaust gas loss to rise. The exhaust
gas loss can be calculated as follows:
q
A
= exhaust gas loss in %
t
A
= exhaust gas temperature in °C
t
L
= combustion air temperature in °C
CO
2
= volumetric content of carbon
dioxide in %
O
2
= volumetric content of oxygen
in %
q
A
t
A
t
L
∠ ( )
A
1
C O
2
- - - - - - - - - - - - B
+ 


⋅ =
In any case of trouble proceed with
checking the basic conditions for a
proper operation of the boiler
system:
1. Is electric power available?
2. Is ther any gas pressure?
3. Are the shut-off valves opened?
4. Are all control and safety instruments
such as boiler thermostat, water
supply failure cut-out, limit switches,
etc. properly set?
1. Ignition failure
Cause Remedy
Ignition
electrode short
circuit. Adjust
electrodes.
Wide ignition
electrode
spacing. Adjust
electrodes.
Dirty and wet
electrodes. Clean
electrodes.
Cracked
insulator. Replace
insulator.
Defective
ignition
transformer. Replace
transformer.
Defective
automatic
furnace
controller. Replace
controller.
Burnt ignition
cable. Replace cable;
search for cause
and eliminate.
Pilot burner
failure. Adjust ignition
gas pressure
Ignition gas
valve does not
open. Search for cause
and eliminate
Defective
solenoid. Replace
2. Motor running failure
Cause Remedy
Motor protection
relay and fuses. Check and
replace if
required.
Air pressure
switch not
changed over or
defective. Check and
replace if
required.
Defective motor. Replace motor.
Defective power
contactor. Replace
contactor.
Air fan motor
starts but stops
after 20-25 secs. Check for
solenoid leaks
Air fan motor
starts, but stops
after about 10
secs in pre-
ventilating mode. Air pressure
switch fails to
change over;
replace switch if
defective; clean
switch if dirt has
accumulated;
check electrical
connections.
3. No response to flame by
automatic furnace controller
with flame sensor
Cause Remedy
Dirty flame
sensor. Clean flame
sensor.
Burner fails to
start. Check
connection of
automatic
furnace
controller.
Trouble lamp
lights; flame
trouble. Unlock and
search for cause
Ionisation
current too
weak. Check
combustion
setting.
Burner starts
without flame
formation.
Solenoid valve
fails to open. Defective coil or
rectifier.
Check
connection.
Lack of gas or
gas pressure too
low. Check gas
pressure
controller, gas
valve, gas filter.
Is the equipment
gas cock open?
Example:
Data measured in natural gas mode:
CO
2
content of exhaust gases 10,8%
Exhaust gas temperature 195°C
Air intake temperature 22°C
The exhaust gas loss can be calculated
as follows:
Natural
gas
Town
gas
L.P.G.
A
1
= 0,370 0,350 0,420
B = 0,009 0,011 0,008
en