25
221873B
11.1 Servicing or Replacing Parts
To ensure the continued efficient and safe operation of the
boiler it is recommended that it is checked and serviced as
necessary at regular intervals.
The frequency of servicing will depend upon the particular
installation conditions and usage, but in general once a year
should be enough.
The servicing of this boiler must be carried out by a competent
person in accordance with the rules in force in the countries of
destination.
NOTE: To obtain a products of combustion reading, remove
the cap from the analyser probe positioned on the top of the
boiler, see diagram 12.7. Disconnect the analyser tube after
use replace the cap.
Typical values for this boiler at maximum domestic hot water
demand is:- CO
2
= 5.8 - 7 and CO < 0.006. These are based
on a 300mm length rear flue.
Make sure the appliance does not modulate whilst checking
combustion and allow the appliance to warm up for 15 minutes
before taking a reading.
Unless stated otherwise, parts removed or renewed during
servicing should be fitted in the reverse order to removal.
After completing any servicing, or renewing of gas carrying
components, ALWAYS test for gas soundness and carry out
functional checks of controls.
Dispose of all used sealing washers, gaskets and “O” rings
when renewing components.
Use the new ones supplied with the replacement.
11.2 Data Label
The data label is positioned on the inner case front refer to
diagram 1.2.
11 General Data
11.3 Isolation of Boiler
Before starting any servicing or the replacement of parts, isolate
the boiler from the electrical supply at the external isolator.
When servicing or replacing any cold/hot water or heating system
components close all water cocks and drain appliance.
Close the gas service cock, see diagram 6.1.
BEFORE DRAINING THE BOILER, REFER TO SECTION 11.6.
11.4 Outer Case Front Removal
Remove the two nuts securing the outer case front then lift up
unhook the case at the top from the threaded lugs, pull it off on
one side to release then remove, see diagram 10.5.
11.5 Inner Case Front
Remove the inner case front, secured by two clamps at the
bottom lift up and unhook at the top, see diagram 8.1.
11.6 System Pressures and Draining
All parts containing water of the central heating circuit within the
boiler, are under the system pressure. Before any parts of this
circuit are disconnected, reduce the system pressure at the
external draining tap, turn the central heating isolating valves off,
and drain at the drain points on the appropriate valves, see
diagram 6.1.
All water containing parts of the domestic hot water circuit of the
boiler will be under the supply water pressure. Before any parts
of this circuit are disconnected, turn the domestic cold water
isolating valve off, open the hot water taps to reduce the water
pressure in the boiler, close the hot water isolating valve and
drain the boiler at the valves, see diagram 6.1.
After replacing any water containing part of the central heating
circuit, make up the water loss, vent all air and pressurise the
system. Refer to “Commissioning” in the Installation Instructions.
Check for water soundness and that the safety valve seats
without leaking.
REMEMBER, When replacing a part on this appliance, use only
spare parts that you can be assured conform to the safety and
performance specification that we require. Do not use
reconditioned or copy parts that have not been clearly authorised
by Hepworth Heating Ltd.
12.1 Isolation and Access REAR FLUE ONLY
Before commencing, refer to Section 11.
Remove the combustion chamber panel, unhook and lift off,
see diagram 8.2.
Remove the fan electrical connections by pulling the boots not
the wires and air pressure switch tubes, see diagram 8.3.
Remove the fan and flue collector assembly by pulling it forward
see, diagram 8.3.
Disconnect the three electrode leads, see diagram 12.1 (White
lead sensing electrode).
Remove the left hand section of the burner base baffle, secured
with two screws, see diagram 14.24.
Remove the burner retaining bracket by sliding it out, see
diagram 12.4.
Carefully pull the burner forward to remove, see diagram 12.5.
Take care not damage the combustion chamber insulation.
12 Servicing
12.2 Isolation and Access HORIZONTAL TOP
FLUE OUTLET ONLY
Before commencing, refer to Section 11.
Remove the combustion chamber panel unhook and lift off, see
diagram 8.2.
Remove the fan electrical connections by pulling the boots not
the wires and air pressure switch tubes, see diagram 12.2.
Remove the fan.
Remove flue collector assembly by pulling it forward, see
diagram 12.3.
Disconnect the three electrode leads, see diagram 12.1 (White
lead sensing electrode).
Remove the left hand section of the burner base baffle, secured
with two screws, see diagram 14.24.
Remove the burner retaining bracket by sliding it out, see
diagram 12.4.
Carefully pull the burner forward to remove, see diagram 12.5.
Take care not damage the combustion chamber insulation.
