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STRATA1
3 8 & 3 8 / 4 6 C O M B I
21.1 inspection (contd)
i) Turn off the boiler and disassemble the burner by removing the six M6 nuts around the burner door,
removing the ignition cable and pulling the burner forwards. When the burner has been pulled forwards
to halfway across the burner area, the plug on the fan cable must be removed from the fan motor.
Check the interior of the heat exchanger.
j)
Open the syphon cleaning rinsing point at the base of the unit with suitable receptacle below to collect
syphon contents. Refit rinse point cap after flushing.
k) Disassemble the plastic box at the suction side of the fan, inspect the fan blades.
l)
Check the distance between the electrode and the burner earthing rod; this should be 4 to 5 mm.
m) Check water treatment dosage level.
21.2 maintenance
Depending on the results of the inspection, carry out any maintenance and if necessary any preventive
maintenance. Possible actions following inspection (21.1) include:
at a) The remarks and comments of the client must be taken seriously and the cause(s) of any faults or
problems must be found.
at b) The pressure of the installation must be between 1 and 2 bar when hot (not less than 0.5 bar cold):
any possible leaks in the system must be identified; if necessary, have a pipework engineer solve
the problem.
at c) Possible leaks or weeping must be resolved immediately.
at d) In case of water leakage or ingress from the air supply pipe, the cause must be found and rectified.
at e) Draw your conclusions from the service screen of the service software program (available from
MHS Boilers spares department) and attend to those parts that have caused any faults.
at f ) and at g)
If necessary, adjust the gas setting on the gas valves.
at h) If the in built pump makes an un-natural noise, and in particular if the pump is more than 5 years
old, it is recommended that the pumps should be replaced by way of preventive action.
NOTE: The pump is modulating and does have characteristic “yet yet” noise which is normal at
low speeds.
at i)
NEVER CLEAN THE BURNER ITSELF.
If the interior of the heat exchanger is contaminated and/or there is a deposit on the surfaces of
the coiled stainless steel pipes, the latter must be removed with a natural bristle brush. Strata heat
exchanger cleaning granuals can be obtained from MHS Boilers spares department. (DO NOT USE
A STEEL BRUSH !) Then remove any dirt with a vacuum cleaner.
at j)
The syphon must be rinsed. With the burners removed, use a filling hose to insert water into the
heat exchanger, which will automatically reach the siphon. Allow the water to run clear prior to
refitting the rinse point cap.
at k) If dirt has deposited on the fan blades, each blade must be carefully cleaned, until the blade material
is visible again. If this is not done evenly the fan will not rotate properly and be out of
balance.
at l)
Carefully bend the electrode without touching the burner, until the correct distance has been
reached. Adjust only the angle of the bend nearest the ceramic insulator. Do not use tools. Firm
finger pressure is all that is required.