Boiler Servicing
55
Operate the automatic cleaning function
in both heat exchangers, as follows:
• Set the ON/STANDBY switch to
STANDBY.
• Re-fit the 5-way plug (on the lead
from the hopper) into the socket at
the left rear of the boiler. Refer to
Figure 11-1.
• Replace the 5A fuse in the fused
spur and switch on the electrical
supply to the hopper and boiler.
The burner fan should briefly run.
• Press and hold down the
‘CLEANING’ switch, on the boiler
control panel, in the ‘TEST’ position
for about 60 seconds.
• Release switch to automatically
reset cleaning function back to
‘AUTO’.
Note that setting this switch to
‘TEST’ does NOT operate the burner
cleaning function, but only that of
the two heat exchangers.
Ensure the electrical supply to the
hopper and boiler is isolated by
disconnecting the 4-way plug from
the socket (on the flying lead) at the
rear of the hopper.
Primary heat exchanger – clean as
follows:
• Remove all of the mild steel spirals
by lifting them vertically up and out
from the primary heat exchanger
tubes.
• Clean down any ash inside tubes,
using a suitable pipe brush, into the
combustion chamber and ash pan
below.
• Clean all ash deposits from top
chamber of the primary heat
exchanger (above tubes) and
shaker mechanism/plates, using
brush and vacuum.
• Clean and check condition of all
spiral baffles.
• Re-fit spiral baffles into heat
exchanger tubes, fitting them
through shaker plates.
• Lift and drop each spiral to check
that all spirals are free to move in
their respective tubes.
Secondary heat exchanger – clean as
follows:
• Shut off cold water supply to wash
system manifold.
• Remove the securing clip from the
end of the solenoid valve shaft.
Then separate solenoid head from
valve body.
• Unscrew the two screws securing
the manifold pipe flange to the
boiler side panel.
• Carefully remove the wash system
manifold pipe through the side of
the secondary heat exchanger and
boiler.
• Check and clean the manifold tube
thoroughly, ensuring that all the jets
are clear. Rinse inside of manifold
pipe to ensure all ash deposits and
other debris is removed.
• Remove all of the stainless steel
spirals from the secondary heat
exchanger tubes.
• Clean down any ash inside tubes,
using a suitable pipe brush, into the
base of the condensing heat
exchanger below.
• Clean all ash deposits from top
chamber of secondary heat
exchanger (above tubes) and from
rear flue gas duct (at rear of
secondary heat exchanger) using
brush and vacuum.
• Clean and check condition of all
spiral baffles. Replace if necessary.
• Re-fit baffles into heat exchanger
tubes, such that all the top edges of
the baffles are running ‘front to
back’. Refer to Figure 11-5.
• Re-fit wash system manifold tube
using the two screws previously
removed, but do not tighten at this
stage (the wash system manifold
needs to be correctly aligned once
the boiler power supply is
reconnected).
• Re-fit solenoid head to valve body
and secure in place with the spring
clip.
Test the automatic cleaning functions as
follows:
• Check the ON/STANDBY switch is
set to STANDBY.
• Re-connect the electrical supply to
the hopper and boiler by fitting the
4-way plug into the socket (on the
flying lead) at the rear of the hopper.
The burner fan should briefly run.
• Press and hold down the
‘CLEANING’ ‘TEST’ switch on the
boiler control panel.
Primary Heat Exchanger
Check the shaker unit (located in the
top of the primary heat exchanger) is
operating freely and that the spirals are
moving up and down with two
intermittent vertical motions.
If there is no movement of the shaker
system, isolate the electrical supply and
check that:
• the motor and cam is rotating.
• the cam follower is in contact with
the cam.
• the condition of the cam follower
spring (located in the rear of the
control panel). Replace if necessary.
Secondary heat exchanger
Check the wash system manifold
(located under the top rear access
door) is spraying water directly into
each flue gas tube of the unit. Refer to
Figure 11-4.
If the water jets are not spraying directly
into the flue gas tubes, adjust the spray
as follows:
• Slacken the two screws securing
the manifold pipe flange to the
boiler side panel.
• Carefully rotate the pipe until jets
spray directly into tubes.
• Tighten the two screws to secure
manifold pipe in this position.
Inspect the condition of the two access
panels before re-fitting. Replace any
damaged or worn rope seal or gaskets
if necessary.
Refit both front and rear access panels
and secure with the nuts previously
removed. Do not overtighten.
Ensure that the rear access panel is
fitted with the flue gas sample point in
the rear left hand corner.
Ensure that fingers are clear of all
moving parts inside the top of the
primary heat exchanger BEFORE
operating ‘CLEANING TEST’ switch.
!
WARNING
To Next Page
Loading...
