Lochinvar EcoForce EF80 Installation, Commissioning, User And Maintenance Instructions page 115

Point of view in next picture 
25.5.8 Burner door gaskets
When these gaskets have changed colours at some parts, the rubber has cured and/or has damages, these gaskets must be replaced. Notice:
only use the gaskets that are supplied by the water heater manufacturer.
25.5.9 Fan
When the fan blades are polluted and dirty, carefully clean the blades with a soft brush. Notice: Do not use too much force on the blades or
else the fan might be out of balance and run irregularly, causing noises and fan failures. Check the fan also for any water damages. In doubt
always replace the fan of the water heater.
25.5.10 Insulation
The insulation of the heat exchanger (located on the rear wall inside the heat exchanger and burner door) must be inspected. If this insulation
disk shows any signs of (water) damage or degradation it should be exchanged. Also check if there are any indications of a high condensate
level in the burner room (caused by a blocked siphon) that might have wetted the rear wall insulation. When this has happened the rear wall
insulation should also be replaced.
Only use the insulation disk that is supplied by the water heater manufacturer.
The same procedure must be applied on the insulation and gaskets fitted on the burner door.
25.5.11 Siphon
Disassemble the siphon and clean every part of it. Check the siphon connection of the heat exchanger for any blocking or pollution and clean
it (if necessary). Check the functioning of the siphon by pouring clean tap water in the burner room (when burner door is removed). This water
will exit the heat exchanger by the siphon. Notice: Don't wet the rear wall insulation.
When mounting the bottom part of the siphon, before commissioning the boiler and/or after maintenance, the
siphon must ALWAYS be FILLED COMPLETELY with water.
This is a safety measure: the water in the siphon keeps the flue gases from leaking out of the heat exchanger via
the condensate drain.
25.5.12 Heat exchanger and Combustion chamber
After the removal of the complete burner unit, check if there is any debris and dirt in the heat exchanger. The coils of the heat exchanger can
be cleaned by using a non-metallic brush. After this the dirt and dust can be removed with a vacuum cleaner and by flushing the Combustion
chamber with water. Don't forget afterwards to clean the siphon once again.
Cleaning the combustion chamber with acid or alkali products is prohibited.
D = 8 - 10 mm
D = 0.315 - 0.393 inch
3.5 mm / 0.14 inch
D
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