Plant maintenance and energy efficiency audits

Person responsible for operation and maintenance

In accordance with Article 11, paragraphs 2 and 8, of Presidential Decree No. 412 of 26 August 1993, the person responsible for the operation and maintenance of the heating system is the occupier of the property unit, whether a tenant, lessee, owner or borrower, or, on their behalf, the person entrusted with the maintenance of the system (for example, a specialist firm with which a contract is entered into).
In the case of buildings fitted with centralised heating systems, managed as a block of flats, the obligations and responsibilities incumbent upon the owner are to be understood as applying to the Administrators. In the case of property units fitted with independent heating systems, the occupier of the property unit, in whatever capacity, assumes, for the duration of their occupation, the role of the owner in fulfilling the obligations and associated responsibilities, limited to the operation, maintenance of the system and the required periodic inspections.
The person responsible for the operation and maintenance of the system, where they do not meet the necessary requirements or do not intend to carry out the work themselves, shall entrust the maintenance operations to persons authorised to carry out extraordinary maintenance on heating systems.

Maintenance of systems and energy efficiency checks

Inspections and any necessary maintenance of the system must be carried out, as provided for in Article 7 of Presidential Decree No. 74 of 16 April 2013, by companies authorised pursuant to the Decree of the Minister for Economic Development of 22 January 2008, No. 37, in accordance with the requirements and at the intervals set out in the technical instructions for use and maintenance provided by the company that installed the system in accordance with current legislation.
Should the installation company not have provided its own specific instructions, or should these no longer be available, inspections and any maintenance of the appliances and devices forming part of the heating system must be carried out in accordance with the requirements and at the intervals set out in the technical instructions relating to the specific model, drawn up by the manufacturer in accordance with current legislation.

As provided for in Article 8 of Presidential Decree No. 74 of 16 April 2013, during the inspection and any maintenance operations referred to in Article 7 on winter heating systems with a nominal useful thermal output exceeding 10 kW and on summer air-conditioning systems with a nominal useful thermal output exceeding 12 kW, an energy efficiency check must be carried out on:

1. the generation subsystem as defined in Annex A to the Legislative Decree;
2. verification of the presence and functionality of central and local temperature control systems in air-conditioned premises;
3. verification of the presence and functionality of water treatment systems, where provided for.

The results of these checks must be recorded in the air-conditioning system logbook and form an integral part of the documentation that must be kept with the system and presented to provincial officials in the event of an inspection. Templates for the Energy Efficiency Inspection Reportsare available on the Ministry’s website, as is the system logbook, of which we also provide the provincially customised version as an attached document. 

Example of maintenance carried out in March 2012 on a natural gas boiler installed in October 2010.

• Inside the condensing boiler
• Boiler heat exchanger
• Close-up of scale deposits
• Scale deposits found
• Cleaned hemispherical burner

The boiler was heavily encrusted, and combustion residues are clearly visible where they have accumulated in the lower part of the heat exchanger.
If the boiler is not serviced regularly, over time the scale and combustion residues will reduce the system’s efficiency and compromise its safety. This has a negative impact on energy consumption and personal safety. A properly maintained system reduces energy consumption and is safer.

To carry out maintenance to the highest standard, the maintenance technician must perform the following operations:

1. remove the burner from the boiler body;
2. thoroughly clean the heat exchanger, removing all scale deposits, including from inside the various components;
3. clean the burner and refit it;
4. clean the boiler of dust and foreign matter, both inside and out;
5. carry out a leak test on the gas supply system;
6. carry out a flue gas test, recording the combustion parameters (including efficiency);
7. check that the combustion parameters and the room where the boiler is installed comply with regulations;
8. visually inspect the condition of the chimney or flue;
9. check the pressure in the expansion vessels and, if necessary, restore the correct pre-charge pressure;
10. check the water hardness and the presence (where necessary) of a water treatment system for domestic hot water and the heating circuit;
11. always complete the energy efficiency inspection report at the end of the operations, regardless of whether the energy efficiency test (flue gas test) has been carried out; this test is not required for winter heating systems with a useful heat output not exceeding 10 kW, summer cooling systems with a useful heat output not exceeding 12 kW, and for all systems using renewable energy sources.

Efficiency of gas or liquid-fuelled boilers

You can calculate the efficiency of your gas or liquid-fuelled boiler (in accordance with Annex B of Presidential Decree No. 74 of 16 April 2013) using the following link:

Calculate your boiler’s efficiency

Boilers fuelled by solid fuels are excluded.

The result of the instrumental efficiency test has a tolerance of +/- 2.0, in accordance with standard UNi10389-1. Therefore, to account for measurement uncertainty, the values read from the instrument must be increased by 2 points before being compared with the calculated values.