Routine Servicing - Benchmark Alpha E-Tec Plus 28 Installation And Servicing Instruction

7

ROUTINE SERVICING

To ensure efficient 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 per year is required as a minimum.
It is the law that any service work must be carried out by a competent person, i.e. Gas Safe registered engineer.
Appropriate personal protective equipment should be worn.
Warning: Before servicing the boiler, isolate the electrical supply and close the boiler gas service cock. Allow the
boiler to cool.
Always test for gas tightness after servicing any gas carrying components.
Always carry out electrical system checks i.e. Earth Continuity, Resistance to Earth, Short Circuit and Polarity
with a suitable meter before and after servicing.
General
Please Note: During routine servicing, and after any maintenance or change of part of the combustion circuit, the
following must be checked:
1. The integrity of the flue system and the flue seals, as described in Section 5.6 and 5.7.
2. The integrity of the boiler combustion circuit and relevant seals.
3. The operational (working) gas inlet pressure at maximum rate.
4. The combustion performance, as described below and in Section 6.6.
Competence to carry out the check of combustion performance
Please Note: BS 6798:2009 Specification for installation and maintenance of gas-fired boilers of rated input not
exceeding 70 kW net advises that:
1. The person carrying out a combustion measurement should have been assessed as competent in the
use of a flue analyser and the interpretation of the results.
2. The flue gas analyser used should be one meeting the requirements of BS 7927 or BS-EN 50379-3
and be calibrated in accordance with the analyser manufacturers' requirements.
3. Competence can be demonstrated by satisfactory completion of the CPA1ACS assessment, which
covers the use of electronic portable combustion gas analysers in accordance with BS 7967, Parts 1
to 4.
Combustion check
Connect the flue gas analyser to the flue gas sampling point as shown in Fig. 6.3.
Notes: 1. Prior to servicing, it is recommended that a flue gas analyser is used to measure the performance of the boiler
(refer to Fig. 6.3 for the position of the flue sampling point). Refer to Section 6.6 Checking combustion. If the CO/
CO ratio measured is greater than 0.004 or when other checks or comments from the customer have indicated
2
that there may be problems, check the following:
Any flue gas recirculation in the flue system or boiler casing.
Any restrictions or blockages in the flue system.
The gas supply pressure and gas rate are correct.
If these are correct then cleaning of the burner and checking the electrode will be necessary. All Sections 7.1, 7.2,
7.3, 7.4 and 7.5 must be carried out. After reassembling the boiler repeat the flue gas analyser test and check
that the CO/CO
If the CO/CO ratio reading is still above 0.004, check again for flue gas recirculation, flue restrictions or blockage
2
and insufficient gas supply pressure. If correct, repeat the procedure above until you obtain a ratio reading of
below 0.004.
If the combustion reading is greater than the acceptable value AND the integrity of the complete flue
system and combustion circuit seals have been verified and the inlet gas pressure (and gas rate) have
been verified. Please call our Technical Helpline.
2. If the CO/CO ratio measured is less than 0.004 and other checks and comments from the customer suggest
2
there are no problems then only Section 7.1 and Section 7.3 paragraphs 1, 2 and 3 need to be carried out to
allow a visual check of the components within the room sealed chamber.
Note: For any maintenance operation not shown, contact Alpha Innovation Helpline.
ratio is less than 0.004.
2
Alpha E-Tec Plus 28, 33 and 38 - Routine Servicing
37