Baxi Combi Instant 80e Installation & Servicing Instructions Manual page 27

Burner Pressure Test
Point Sealing Screw
Inlet Pressure Test
Point Sealing Screw
Fig. 34
Plastic
Protection
Cap
Modulator
Wire
Maximum Rate
Adjustment Nut
Minimum Rate
Adjustment Nut
Fig. 35
Selector Switch
30° 40° 50° 60° 70° 80°
Power On
Neon
Central Heating
Temperature Control
Fig. 37
Gas Valve
bar
Fig. 36
PREHEAT
OFF
ON
Hot Water
Temperature Control
9.0
9.2
1. Turn on the gas and electrical supplies to the boiler
and ensure that all external controls are calling for heat.
2. Set the hot water and central heating temperature
controls to maximum and the selector switch to the
OFF position (Fig. 37).
3. Slacken the pressure test point sealing screw (Fig. 34)
on the gas valve and connect a pressure gauge.
4. Disconnect the sensing tube from the gas valve
(Fig. 34).
5. Turn the selector switch fully anticlockwise against the
spring pressure to position R and hold for 2 seconds to
reset the boiler.
6. Turn the selector switch to the Central Heating and
Domestic Hot Water position (
neon ( ) will illuminate (Fig. 37).
7. Turn on a hot water tap to give a flow rate of at least
10 l/min.
8. The pressure should be :-
2
NG
Butane
Propane
Pressure Gauge
If not, check that the gas supply pressure is correct
(Natural Gas 20mbar, Butane 30mbar and Propane
37mbar).
Also check that the working pressure at the gas valve is
2
not more than 1mb lower than that at the gas meter.
bar
9. The pressure can be adjusted if required.
10. To check and set minimum pressure first remove
one of the modulator wires.
Adjusting the Pressure (Fig 35)
11. Remove the plastic protection cap from the pressure
adjustment nuts on the valve.
12. The smaller nut (5mm) adjusts minimum pressure
and the larger nut (8mm) maximum pressure.
13. Using a suitable spanner adjust the relevant nut until
the correct pressure is achieved.
14. Once the pressure has been set turn the boiler off
and disconnect the pressure gauge.
15. Tighten the pressure test screw and refit the
modulator to the valve. Reassemble in reverse order.
Commissioning the Boiler
Checking the Burner Pressure
). The power ON
Instant Instant
80e 105e
12.2mbar 13.4mbar
28.3mbar n/a
36.2mbar 35.8mbar
27