Table of Contents
Advertisement
FAULT FINDING AND DIAGNOSIS
Display
Cause
No flame ionization detected
when water flowing.
Ionization failure during
operation.
Ionization fault at standby.
Gas leakage error, gas valve
circuit not closing properly.
Tab. 27
* By qualified registered gas engineer only.
54
Solution
1. Verify that all manual gas isolation valves are open.
2. Check gas type.
3. Check inlet gas pressure.*
4. Reset fault code and open a hot water tap to cycle the
heater in an effort to release air from the hot water system.
Cycling hot water tap on and off multiple times may be
necessary. If heater still shows fault code EA, have a Gas Safe
registered engineer properly purge the gas line leading to the
water heater.
5. Check three wiring connections on the lower front of the
heat exchanger are secure.
6. Check flue requirements are met. Improper flueing may
cause premature failure of the flame sensor rod.
7. Check the minimum power fan speed has been adjusted to
the proper value. (
chapter 9.7).
8. Inspect the inside of the combustion through the sight glass.
Sparking should be followed by a steady blue flame. If flame is
unstable/yellow with sufficient gas pressure, check CO
readings.*
1. Check gas type.
2. Check inlet gas pressure.*
3. Check three wiring connections to ignition group on the
lower front of the heat exchanger are secure.
4. Verify that flue requirements are met. Improper flueing may
cause premature failure of the flame sensor rod.
5. Check the minimum power fan speed has been adjusted to
the correct value. (
chapter 9.7).*
6. Check CO
readings.
2
1. Undo connection to the flame ionization sensor. Verify that
the thinner wire leading from the control unit is securely
connected to the electrodes located on the lower front of the
heat exchanger.
2. Flame ionization sensor or control unit may be damaged.
Call Technical Support.
1. Disconnect power supply and check wiring connections on
gas valve and the two connectors on the control board.
2. Draw water from a hot water tap above the minimum
activation point (1.9 l/m). Measure voltage at the gas valve
wiring connection. The voltage should measure 24VDC
between the left pair of wires and 24VDC between the right
pair of wires when the unit is in operation. If voltage is not
insufficient, call the Technical Assistance.*
3. Gas valve may be defective, call Technical Support.
6 720 646 322 (2012/05)
2
Hide quick links:
Advertisement
Table of Contents
