Potterton Performa 30 HE Installation & Service Instructions Manual page 49

Domestic Hot Water - Follow operational sequence
Turn selector to
neon illuminated
YES
Turn thermostat to max.
Open DHW tap fully. DHW
flow switch operated
YES
Primary water is diverted
from CH system to DHW
heat exchanger and flow
microswitch operated
neon illuminated
YES
Pump runs
YES
Primary flow switch operated
YES
Fan runs at max speed
YES
Air pressure switch proved
YES
Spark at ignition electrodes
for up to 10 seconds
YES
Burner on neon
illuminated
YES
Burner extinguishes
after 10 seconds
NO
Burner output modulates to
maintain temperature set at
thermostat
YES
Close DHW tap
YES
DHW flow valve
senses no flow.
Primary water diverted to
CH system. DHW flow
switch released off
YES
Burner goes out
© Baxi Heating UK Ltd 2009
NO
Go to section 'A'
Is mains water
filter and differential
assembly clean?
YES
NO
DHW flow rate more than
2.5l/min.
Continuity across DHW flow
NO
microswitch terminals and
PCB - A5 connector
terminals 5 & 6
NO
neon flashing
Go to section 'B'
NO
neon flashing
Go to section 'C'
NO
neon flashing
NO
neons flashing
Go to section 'D'
NO
neon flashing
Go to section 'E'
NO
neon flashing
NO
Replace PCB
NO
Go to section 'F'
YES neon flashing
Go to sections 'I' & 'L'
Reduce the DHW flow rate.
NO
If burner does not modulate
clean DHW temperature
sensor and DHW heat
exchanger. If modulation
does not occur go to section
'G'
NO
Diverter valve spindle
assembly faulty
NO
Fan stops
16.0
Replace diaphragm
YES
YES
DHW flow valve diaphragm
damaged
NO
DHW flow valve rod
obstructed
Replace DHW flow
NO
microswitch
YES
Replace PCB
Turn selector to reset
position. If regular resetting is
YES
required or appliance still
does not operate
investigation is necessary
Turn the selector to the reset
YES
position. If the light does not
extinguish go to section H &
K
YES
Pump stops
Fault Finding
Go to sections 'J' & 'M'
YES
Operation sequence correct
49