andrews COMBIflo 100/300 Installation, Operation And Maintenance Manual page 61

6.2.12 COMBUSTION FAN
Electrical connectors
• Turn OFF the electricity to the appliance and isolate the gas supply.
• Carefully remove the electrical connectors of the fan, gas valve and ionisation electrode. Secure the wiring
loom out of the work area.
• Disconnect the air snorkel from the main air stack.
• Remove the two venturi screws and remove the four gas valve securing screws. Gently remove the gas
valve and air snorkel assembly and place to one side. Inspect the cork venturi gasket and replace if dam-
aged.
• Undo the top two 8mm fan nuts, but do not completely remove them from their thread. Completely remove
the bottom two 8mm fan nuts and withdraw the fan the heat exchanger door.
• Check the condition of the cork gasket and replace if damaged, before fi tting the new fan.
• Before refi tting the four gas valve securing screws ensure that the black O ring gasket is undamaged and
correctly placed in the recess of the gas isolator cock.
• Replacement is the reverse
• Operate the heat engine and check for gas leaks
• After fi ve minutes check the rate and combustion is correct to the table on page 8. Adjust using the throttle
screw on the gas valve clockwise to decrease CO
for details)
CAUTION
Please ensure that the cork gasket between the fan and the venturi is correctly placed before fi xing
the two venturi screws. The top edge of the gasket should be visible between the fan and the ven-
turi (see illustration)
6.2.13 VENTURI
• Follow instructions 6.2.12 above, but do not remove the fan.
• Remove the air snorkel from the venturi by compressing the spring clip with a pair of pump pliers and pull-
ing the hose off
• Separate the gas valve from the venturi by removing the 3 cross head screws.
• Check the condition of the gaskets for damage and replace as necessary. Ensure that gaskets are fi tted to
the new venturi or positioned on the fan before securing the venturi into place (see warning above).
• Replacement is the reverse.
• Operate the heat engine and check for gas leaks.
• After fi ve minutes check the rate and combustion is correct to the table on page 8. Adjust using
tle screw on the gas valve clockwise to decrease CO
5.2.1 for details)
ANDREWS COMBIfl o
Gas
isolator
Air
Snorkel
Ionisation Venturi
electrode screws (x2)
, anti-clockwise to increase CO
2
, anti-clockwise to increase CO
2
59
if required. (see 5.2.1
2
Gasket visible from top
Gas valve
securing
screws (x4)
8mm Fan
nuts (x4)
NB: Do not
completely
remove
top nuts
the throt-
if required. (see
2
GB