PENSOTTI PCH 50B-H Instruction Manual page 64

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 "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
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;
Expansion vessel (see fig. 2)
Close the shut-off valves and drain the central
heating circuit of the boiler.
Use a 19 mm spanner to unscrew the pipe
coupling to the vessel.
Unscrew the fixing screws and remove the
upper mounting
expansion vessel from the left side of the
boiler.
Replace the expansion vessel 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;
INSTALLATION INSTRUCTIONS
following the above
bracket. Remove
primary heat
exchanger
Fig. 1
stainless steel
pipe coil
A
the
B
Fig. 2
flue connection
chamber
expansion vessel
A
fixing bracket
B
ceramic fibre
washer
61