Keston 50 - GC Installation And Servicing Instructions page 44

WD50/2/1997 Chapter 6 : Servicing
Pressure Test
Point B
Burner Heat (From Above)
6.2 Recommended Routine Service
a.
b.
Installation & Servicing Instructions
Pressure Test
Point A
Fig 6.1.1 Pressure Test Point Locations
v) Turn off the electrical supply to the boiler.
vi) Remove the pressure point screw from point C and transfer the tube from
point A to C, replacing the screw on point A.
vii) Turn on the electrical supply to the boiler (gas still off), wait for the fan to
reach full speed.
viii) The pressure difference should be below 11 mbar. If not, clean heat
exchanger.
ix) Disconnect the gauge from point B. Refit the screw.
x) Read pressure of point C.
xi) The maximum pressure should be 3 mbar. If the pressure is greater than
this, check the flue for blockage.
xii) Turn off the electrical supply to the boiler.
xiii) Remove the pressure gauge tube and refit the screw.
xiv) Open the gas service cock.
Inspect the air filter located at the top right hand side of the boiler. Release the
projecting leaf on the filter box and slide out the filter.
If the filter looks dirty remove the dirt with a vacuum cleaner or by other means. If
in any doubt renew the filter element.
Remove the burner head (Section 7.7) and inspect the burner appearance. Black
markings or other discolourations on the gauze indicate too much gas or a lack of
air possibly due to a blocked air filter. Any breakages or damage to the burner
mesh indicate the burner must be replaced.
Page : 41
The Keston 50, 60 & 80 Condensing Boilers
Heat
Exchanger
Shell
Flue
Flue Overheat
Thermostat
Combustion
Test Point
&
Pressure Test
Point C