Keston C45 Installation And Servicing Instructions page 45

WD536
b. Remove the burner head (Section 7.6) and inspect the burner appearance. Black
markings or other discoloration's on the gauze indicate too much gas or a lack of
air possibly due to a blocked air inlet. Any breakage's or damage to the burner
mesh indicate the burner must be replaced.
c. If necessary clean the burner with a mild household detergent and rinse under a
hot running tap.
d. If necessary, from visual inspection, clean the heat exchanger using a suitable
stiff plastic bristle brush, vacuum out any large particles and flush the heat
exchanger with fresh water until the water flowing from the condensate drain is
clear.
e. Remove the condensate trap (Section 7.8) and clean by flushing through with
clean running water.
f. Check the electrode assembly mounted on the heat exchanger. If the point is
damaged or burnt replace it.
Check that the spark gap measures 3 mm.
g. Replace the burner head, renewing the gasket if necessary, and reconnect the
gas/air supply. Ensure the flanged gas/air supply joint is air tight.
h. Turn on the electrical supply to the boiler and allow the boiler to reach operating
temperature levels.
i. Remove the combustion test point plug from the flue pipe. This is situated on the
flue spigot out of the cabinet.
j. Carry the full procedure detailed in section 4.7 COMBUSTION TESTING -
MANDATORY
k. Replace the combustion test point plug.
l. Recheck the burner pressure by following the procedure detailed in Section 4.7.
m. Check all joints for soundness up to the gas burner.
n. Complete the Gas Boiler Commissioning Checklist - Service Interval Record
(Chapter 9).
Installation & Servicing Instructions
Chapter 6 : Servicing The Keston C45, C40P, C55 & C55P
Page : 40