23
Compact
7.6.1
SETTING THE MAXIMUM DHW GAS
PRESSURE (fig. 15 & 23)
Isolate the appliance from the electrical supply,
remove the appliance casing as described in
section 4.7.1.
●
Attach a manometer to the outlet test point of
the gas valve.
●
Remove the protective cover from the gas
valve modulator, and disconnect the
compensation tube from the gas valve.
●
Fully open a hot water outlet (preferably the
bath tap).
●
Rotate the DHW temperature selector to
maximum.
●
Restore the electrical supply to the appliance.
●
The appliance will now light and after 7-10
seconds, the burner will be at full power.
●
Observe the manometer, the reading for
Compact 24 should be 10.1 mbar, for Compact
28 the reading should be 10.2 mbar.
●
If the reading is correct, proceed to section
7.6.2
●
If the reading is incorrect, turn the maximum
adjustment screw (fig. 15) clockwise to increase
the pressure, or anti-clockwise to reduce the
pressure.
●
Proceed to section 7.6.2
7.6.2
SETTING THE MINIMUM DHW GAS
PRESSURE (fig. 15 & 23)
●
After carrying out section7.6.1, disconnect one of
the black wires attached to the modulator coil.
●
The burner will now operate at minimum power.
●
Observe the manometer, the reading for
Compact 24 should be 1.5 mbar, for Compact
28 the reading should be 1.3 mbar.
●
If the reading is correct, proceed to section 7.6.3.
●
If the reading is incorrect, turn the minimum
adjustment screw (fig. 15) clockwise to increase
the pressure, or anti-clockwise to reduce the
pressure.
●
Proceed to section 7.6.3
7.6.3
SETTING THE MAXIMUM AND THE MINIMUM
CENTRAL HEATING BURNER PRESSURES
●
Isolate the appliance from the electrical supply.
●
Close the hot water outlet.
●
Re-attach the black wire to the modulator coil.
●
Remove the PCB cover and temporarily attach
a jumper tag to JP2.
●
Rotate the heating temperature selector to
maximum, and ensure all radiators are turned
on with any thermostatic radiator valves set to
maximum.
●
Restore the electrical supply and ensure there
is a call for heat via the appliance time clock
and/or room thermostat.
●
The appliance should now be operating in the
heating mode at maximum output.
●
Observe the manometer, the – maximum –
reading for Compact 24 should be 10.1 mbar,
for Compact 28 the reading should be 10.2
mbar
●
Using a small screwdriver, gently rotate the P5
potentiometer if adjustment is necessary.
●
To check and/or adjust the minimum heating
gas pressure, slowly rotate the heating
temperature selector until the burner pressure
drops to minimum (should be 1.9 mbar).
●
Using a small screwdriver, gently rotate the P4
potentiometer if adjustment is necessary.
●
Isolate the appliance from the electrical supply,
and remove the jumper tag from JP2.
●
Remove the manometer from the gas valve
and tighten the outlet test screw.
●
Refit the PCB cover and appliance casing.
7.7
COMBUSTION ANALYSIS TEST
The appliance has a built-in facility which enables
combustion analysis checks to be carried out. To
activate the combustion analysis mode, proceed
as follows.
Locate and remove combustion test point screw,
(fig. 1) insert flue gas analyser probe into com-
bustion test point, remove mode selector switch
and rotate selector shaft clockwise until it can go
no further, wait until the yellow LED begins to
flash, turn the selector shaft back to the heating
position. The appliance will now enter its com-
bustion analysis mode whereby it will fire at
maximum output in the heating mode for fifteen
minutes, without modulating until the maximum
operating temperature is realised. To gain accu-
rate information, ensure the flue gas analyser
has been set properly, and that the analysis is
carried out when the appliance is on maximum
output. Once the analysis has been completed,
re-fit the mode selector switch, remove the flue
gas analyser probe and replace the test point
screw.
7.8
CHECKING THE EXPANSION VESSEL
Carry out procedure as described in section 6.5.
Using a suitable pressure gauge, remove dust
cap on expansion vessel and check the charge
pressure. The charge pressure should be between
0.7 – 0.8 bar. If the charge pressure is less, use
a suitable pump to increase the charge. Please
note, you must ensure the safety valve is in the
open position whilst re-charging takes place.
Replace dust cap and carry out the relevant
commissioning procedures as detailed in section
6.21.
7.9
ELECTRO-MECHANICAL FAULTS
Before carrying out any fault finding or compo-
nent replacement, ensure the fault is not attribut-
able to any aspect of the installation, for example,
external wiring fault, hot & cold services reversed,
service valves closed, gas supply turned off, etc.
