MAINTENANCE INSTRUCTIONS
45
Primary heat exchanger
(see fig. 1)
•
Close the shut-off valves and drain the central
heating circuit of the boiler;
•
Switch off the power and gas supply to the boiler;
•
Remove and dismantle the entire burner unit (see
6.6.1 “Cleaning the condensation module and
burner unit”);
•
Remove the gas valve;
•
Remove the spring and then the condensate
drainpipe;
•
Remove the fixing springs and then the delivery
and return pipes;
•
Remove the support brackets and pull out the
heat exchanger;
•
Remove the regulation sensor from the old heat
exchanger and refit it together with the two
condensate drainpipes to the new one;
•
Replace the heat exchanger and re-assemble the
components following the above procedure in
reverse order;
•
Switch on the electricity, water and gas supplies
and fill the system with water. Check for any leaks
from the joints and bleed off any air from the
circuit. Restart the boiler, making sure that there
are no gas leaks;
primary heat
exchanger
flue connection
chamber
steinless steel
pipe coil
ceramic fibre
washer
Fig. 1
