Commissioning The Boiler - Baxi Maxflow Combi WM Installation And Servicing Instructions

Facia Panel
Hot Water Temperature
Central Heating Selector Switch
Temperature
Burner Pressure
Test Point
24
RESET
Fig. 36
9.0
9.1

Commissioning the Boiler

1. Reference should be made to BS 5449 Section
5 when commissioning the boiler.
2. Open the mains water supply to the boiler.
3. Open all hot water taps to purge the DHW
system.
4. Ensure that the filling loop is connected and
open, then open the heating flow and return
valves on the boiler.
5. Open the automatic air vent (Fig. 37).
6. The system must be flushed in accordance
with BS 7593 (see Section 6.2) and the flushing
agent manufacturers instructions.
Fig. 35
7. Pressurise the system to 1.0 bar then close
and disconnect the filling loop.
8. Turn the gas supply on and purge the system
according to BS 6891.
9. Test for gas soundness.
10. If at any time during commissioning it is
required to terminate a particular cycle, e.g. the
pump overrun period, turn the selector to the OFF
position and then back to either (
9.2 Checking the Burner Pressure
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 temperature control to
maximum and the selector switch to the OFF
position (Fig. 36). Draw off all hot water to ensure
that the store is cold
3. Slacken the pressure test point sealing screw
(Fig. 38) and connect a pressure gauge.
Disconnect the sensing pipe from the spigot
Fig. 37
adjacent to the pressure test point.
4. Turn the selector switch to the Domestic Hot
Water position and press the white boiler reset
button for 2 seconds (Fig. 36). Open a hot water
tap to give a flow rate of at least 10l/min.
5. Remove the plastic cap and using a suitable
spanner adjust the brass nut to give a maximum
output setting of 10.6 mbar.
Automatic
Air Vent
6. Disconnect one of the modulator wires from the
gas valve. Adjust the red screw to achieve the
correct minimum output setting pressure of
1.7 mbar.
7. Turn the boiler off and reassemble in reverse
order. Tighten the pressure test point sealing
screw and reconnect the sensing pipe.
8. The system should then be flushed in
accordance with BS7593 and the flushing agent
or inhibitor manufacturers instructions.
Commissioning the Boiler
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