21
Mynute
7.5
CHECKING THE EXPANSION VESSEL
Carry out the component removal procedure as
described in 6.4. You must ensure that the boiler
is completely drained of water.
Using a suitable pressure gauge, remove dust
cap on expansion vessel and check the charge
pressure. The correct charge pressure should be
1,0 bar +/- 0,1 bar. If the charge pressure is less,
use a suitable pump to increase the charge.
NOTE
You must ensure the safety valve is in the open
position whilst re-charging takes place. Replace
the dust cap and carry out the relevant
commissioning procedure (section 5).
7.6
EXTERNAL FAULTS
Before carrying out any fault-finding or component
replacement, ensure the fault is not attributable to
any aspect of the installation.
7.6.1
INSTALLATION FAULTS
7.7
ELECTRICAL CHECKS
Any electrical checks must be carried out by a
suitably qualified person.
7.7.1
EARTH CONTINUITY TEST
Isolate the appliance from the electrical supply,
and using a suitable multi-meter carry out a
resistance test. Connect test leads between an
appliance earth point and the earth wire of the
appliance supply cable. The resistance should
be less than 1 ohm. If the resistance is greater
than 1 ohm check all earth wires and connectors
for continuity and integrity.
7.7.2
SHORT CIRCUIT CHECK
Isolate the appliance from the electrical supply,
and using a suitable multi-meter, carry out a short
circuit test between the Live & Neutral connections
at the appliance terminal strip (see fig.16).
Repeat above test on the Live & Earth connections
at the appliance terminal strip (see fig.16).
NOTE
Should it be found that the fuse has failed but no
fault is indicated, a detailed continuity.
Check will be required to trace the fault. A visual
inspection of components may also assist in
locating the fault.
7.7.3
POLARITY CHECK
With the appliance connected to the electrical
supply and using a suitable multi-meter, carry out
the following voltage tests:
●
connect test leads between the Live & Neutral
connections at the appliance terminal strip (see
fig.16), the meter should read approximately
230V ac. If so proceed to next stage. If not, see
7.7.4.
●
connect test leads between the Live & Earth
connections at the appliance terminal strip (see
fig.16), the meter should read approximately
230V ac. If so proceed to next stage. If not, see
7.7.4.
●
Connect test leads between the Neutral & Earth
connections at the appliance terminal strip (see
fig.16), the meter should read approximately 0
– 15Vac. If so polarity is correct. If not, see
7.7.4.
7.7.4
REVERSED POLARITY OR SUPPLY FAULT
Repeat the above tests at the appliance isolator,
if testing reveals correct polarity and/or supply at
the isolator, re-check wiring and connections
between the isolator and the appliance.
If tests on the isolator also reveal reversed polarity
or a supply fault, consult the local electricity
supplier for advice.
7.7.5
RESISTANCE TO EARTH CHECK
Isolate the appliance from the electrical supply,
and using a suitable multi-meter carry out a
resistance test. Connect test leads between the
Live & Earth connections at the appliance terminal
strip (see fig. 16), if the meter reads other than
infinity there is a fault that must be isolated, carry
out a detailed continuity check to identify the
location of the fault.
IMPORTANT
These series of checks must be carried out
before attempting any fault-finding procedures
on the appliance. On completion of any task that
required the disconnection and re-connection of
any electrical wiring or component, these checks
must be repeated.
SYMPTOM
POSSIBLE CAUSE
No ignition
No hot water
No central
heating
Check external wiring.
Check external controls.
Check external controls.
Check external controls.
CO mode button (beneath protective cap)
Fig. 25A
FAULT CODE POSSIBLE CAUSES
01
02
03
04
Gas supply turned off. Gas line requires
purging. Reversed polarity. Broken,
internal flue joint.
Flow/return valves closed. Stuck pump.
Debris in flue system. Debris in flue
venturi. Flue exceeds max. length
Insufficient pressure. Air in boiler.
