IO-752:2018/EN 05.12.2018
12
7 DIAGNOSTICS
During and after the process of production, water heater
is subjected to a whole range of partial and complex
inspections.
In spite of this, during the water heater operation, some
disturbances
– that are not caused by the producer –
may occur.
To make easier diagnostics of possible incorrectness in
the water heater operation, in table below essential
information has been collected. Using this information
allows eliminating some unjustified operations during
the water heater disassembly, and thus makes the time
of repair shorter.
Before beginning the water heater repair, it should
be checked if:
•
water heater is adapted for the gas currently in use,
•
gas pressure is at least minimal,
•
negative pressure in chimney duct is within the
range 3
– 15 Pa (0.03 - 0.15 mbar).
•
battery voltage is adequate
(in
TERMAQ ELECTRONIC
water heater type )
7.1 Igniting system diagnostics
After turning on the water tap, water flowing through the
water heater should initiate the process of burner
igniting, which stages are presented below:
•
clenching/short-circuit/
of
the
microswitch
connectors, fig. 2.2.1.3 item 3.6,
•
sparkling between igniting electrode item 2.1, and
burner segment item.1,
•
voltage occurrence on coil I, item 3.5.1
– valve I in the
differential valve opens (valve I in release state is
closed),
•
gas ignition on one of the burner segment item 1
–
ionisation current occurrence detected by the
control electrode item.2.2,
•
voltage occurrence in coil II item 3.5.2
– valve II in
the differential pressure valve closes (valve II in
release position is open),
•
opening the main gas valve caused by pressure
difference over and under the diaphragm in the
differential pressure valve item 3.5,
•
gas ignition on the whole burner item 1.
7.2 Igniting system checking
In the case of incorrect ignition, it is recommended to
check the ignition system, according to following
instructions:
1. Check the correctness of electric connections,
2.
Connect a voltmeter to the „
-
” pole:
- In
TERMAQ ELECTRONIC ECO
water heaters -
spring in
battery compartment item 6,
- In
TERMAQ AQUA-POWER ECO
water heaters
–
hydrogenerator’ s wire (white, item 7),
3.
Connect a voltmeter to the „
+
” pole:
- In
TERMAQ ELECTRONIC ECO
water
heaters
–
metal plate in
battery compartment item 6,
- In
TERMAQ AQUA-POWER ECO
water
heaters
–
hyd
rogenerator’ s wire (red, item 7),
4. Measure the voltage:
- In
TERMAQ ELECTRONIC ECO
water heaters
–
the battery
voltage -1,5VDC
- In
TERMAQ AQUA-POWER ECO
water
heaters
– the
hydrogenerator’s voltage hydrogenerator’ s at resistance
load 10
and at the flow 3l/min - 1,3
1,6VDC
5. Measure the supply voltage after loading with the
operating ignition system (correct system
operation at the voltage of 0.9-1.5VDC),
6. Check the voltage on the protection against flue
gas outflow into the room item 8 (voltage like on
battery),
7. Check the voltage on the protection against heat
exchanger overheating item 9 (voltage like on
battery),
8. Check the voltage on terminal 9 of the spark
generator, item 5 (voltage like on battery),
9. Close the microswitch connectors item 3.6.
Shorted connectors should cause sparkling
between igniting electrode item 2.1 and burner
segment item 1,
•
check the voltage on coil terminals I, item 3.5.1
(correct operation of the system at voltage 0.9-
1.5V),
•
after detecting the ionisation current by the
control electrode (after flame appearance),
check the voltage on the clamps of coil II, item
3.5.2 (correct operation of the system at
voltage 0.9-1.5V).
7.3 Checking the coils of
differentia pressure valve
Inspection of possible defects on the electric coils of the
differential pressure valve may be performed by
checking the resistance of the coils.
Method of taking the resistance of the coils:
•
take off the muffs from the coils,
•
one of the ohmmeter wire connect to the body of
the differential pressure valve,
•
the other wire connect to one, and then to the next
muff of the inspected coils, every time taking the
value of the resistance.
Correct resistance values:
Coil I - 39
Ω ± 20%
Coil II - 58
Ω ± 20%
