26
Fill the whole system in accordance with BS 7593: 1992
(See Treatment of Water Circulating Systems in the
System Details section). Check for water leaks.
Purge air from supply pipe at gas
service tap (BS 6891).
Turn gas service tap anticlockwise to
ON position. Check for gas
soundness up to gas valve.
Ensure that all external controls, e.g.
room thermostat, timer, etc. are calling
for heat.
Fit thermostat control knob
(packed with the contents
in plastic bag).
Turn anticlockwise to OFF
position, marked O.
Slacken burner pressure test point screw. Connect
pressure gauge.
Press gas control knob fully inwards and
hold.
Press in igniter button and release. Repeat until pilot
ignites. Continue to hold in gas control knob for
approximately 15 seconds and then release. Pilot
should stay alight.
Check the appearance of the pilot flame to
ensure that it envelops the tip of the
thermocouple and is approximately 25mm
long. Check that the thermocouple output
is between 10-15 mV closed circuit.
The pilot pressure is factory set and
cannot be adjusted.
If pilot fails to remain alight, repeat from start
of paragraph above.
COMMISSIONING THE APPLIANCE
Burner Pressure
Test Point
25
