Rinnai aiM 115, User And Installation Manual

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43
Service
Disassembly of the heat exchanger
The following instructions must be followed when it is
necessary to replace the thermal fuse or more generally when
it is necessary to carry out a more accurate maintenance.
aiM 85 - aiM 115 - aiM 150
The instructions refer to the models aiM 85-115-150, equipped
with the Sermeta DUO heat exchanger. In these devices the
thermal fuse is located at the rear of the heat exchanger.
Before disassembling the exchanger, perform the following
preliminary operations:
•
place the boiler on the ground in a horizontal position with
the rear side lying on the ground;
•
disassemble the front and side panels;
•
disconnect the various cables from their respective
terminals;
•
inside the boiler, unhook the gas pipe and the siphon;
•
close the valves on the return and gas branch;
•
remove the fan, the Venturi tube and the gas valve from the
heat exchanger;
•
in the event that the expansion vessel pump is connected
to an external power supply is necessary disconnect it;
Once these operations have been carried out, it is possible
disassemble the exchanger:
1. remove the 4 screws in the lower part of the boiler;
2. remove the 2 screws at each end of the side bars of the
chassis;
3. remove the 4 screws in the upper part of the boiler;
4. remove the 2 screws at each end of the side bars of the
chassis;
NOTE: At this point it is possible to separate the exchanger (still fixed to the rear
panel of the boiler) from the upper and lower parts of the boiler.
5.
remove the Venturi tube and the fan from the exchanger
by unscrewing the 4 bolts. Don’t forget to keep the gasket
inserted between the fan and exchanger;
NOTE: From here on, the components you work on are the heat exchanger, the
rear panel of the chassis, the flow and return pipes and the siphon.
The flow and return pipes are connected to the exchanger
through a reducer and can be removed in case was
necessary.
The steps listed below must be performed on a workbench to
facilitate operations and reduce risk of accidents.
Place the chassis and heat exchanger on a bench for work
with supports (for example in wood). The blocks they must be
at least 50 mm high to avoid damage.
6. unscrew the 3 bolts that hold the plate together heat
exchanger and the rear panel of the chassis;
7. separate the exchanger from the rear panel by doing pay
attention to the rubber tube that connects the exchanger to
the condensate drain siphon.
Once the fuse has been replaced thermal and / or
maintenance, to re-assemble the appliance follow the steps
just listed in the order reverse.