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pressure limiting devices are out of order or concealed, or the parameters do not meet
the ones in the boiler certificate;
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faulty fittings;
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loss of water circulation through the boiler;
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a boiler operating personnel untrained;
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technical maintenance not carried out on time (see Section 9 of these Instructions);
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failure to follow the measures listed in clause 8.2 hereof.
9. MAINTENANCE AND INSPECTIONS
9.1. Boiler technical maintenance inspections must be carried out by the person responsible for
their maintenance.
9.2. Technical maintenance inspections are carried out in the following cases within the below
specified scope:
9.2.1. Internal and external inspection and hydrostatic test pressure of 6 bar – for a newly installed
boiler, a boiler manufactured more than 2 years ago, or a boiler has been damaged during
transportation or installation.
9.2.2. Internal and external inspection and hydrostatic test pressure of 6 bar – for relocated
boilers, as well as after the repair with welding.
9.2.3. Internal and external inspection and hydrostatic test pressure of 6 bar – for boilers in
service, at least once every 5 years.
9.2.4. Internal and external inspection and hydrostatic test pressure of 6 bar – for boilers being in
service over 10 years, at least once per year.
9.2.5. Internal inspection after each cleaning and repair.
9.3. Before the internal inspection and hydrostatic testing, a boiler must be cooled down and
disconnected with valves from the heating surfaces; dirt, soot and ash must be thoroughly
removed.
When carrying out an internal and external inspection, please, pay attention to the state of
boiler walls both inside and outside, funnels and welded joints, as well as to the state of fume
pipes, cleaning vent lids, door sealing, thermal insulation, controls instrumentation, and safety
devices.
9.4. Before carrying out a hydrostatic test, please, thoroughly clean all the boiler fittings, check
their tightness, and conceal safety valves.
9.5. A boiler is hydrostatically tested along with its fittings equipped. The boiler hydrostatic test
must be carried out for 10 minutes; then the pressure is reduced to the operating one and
maintained all the time required for the boiler inspection.
9.6. A boiler is considered to have passed the hydrostatic test if:
9.6.1. no crack signs found;
9.6.2. no leakage found, when the water leaks through threaded, flange fitting connections as fine
dust or droplets;
9.6.3. no permanent deformation identified;
9.6.4. Upon identifying a water leakage a fine dust or droplets in welded joints, on the pressurised
surface or in the above-mentioned joints, upon emergence of crack in seams or permanent
deformation, the boiler shall be considered to have failed the hydrostatic test;
