Short answer: Central heating (hot water) boilers are closed vessels that heat water under pressure for heating purposes and, as pressure equipment, are subject to periodic inspections. Generally, they are inspected at least once a year, including body inspection, safety equipment checks, and expansion system checks.

Although hot water boilers operate at low pressure, a faulty safety valve, a clogged expansion line, or weakening due to corrosion can create a risk of excessive pressure and explosion.

Periodic inspections ensure both life safety and legal compliance by verifying that the boiler and associated safety equipment are operating safely.

What is checked?

• Corrosion and cracks on the casing, water tube/smoke tube surfaces.
• Safety valve opening pressure and discharge capacity
• Expansion tank/reservoir and pressure equalization
• Pressure gauge, thermometer and water level indicators.
• Burner and fuel shut-off safety devices
• Boiler room ventilation and chimney connection.

Method and Standard

Inspection includes internal/external visual inspection and functional testing of safety equipment. Design and safety requirements for hot water boilers. TS EN 12828 (Heating systems) are based on pressurized equipment regulations. The safety valve is verified at an opening value corresponding to the boiler's maximum operating pressure.

Legal Basis and Period

Central heating boilers are subject to periodic inspections under Law No. 6331 and Annex III; these inspections must be carried out by authorized personnel and documented with a report prepared by them.

Common Nonconformities

• Safety valve with insufficient capacity or leaking.
• Expansion tank without pressure/defective
• Loss of yield/strength due to corrosion and limescale.
• Missing or faulty pressure gauge/thermometer

Frequently Asked Questions

According to which standard are hot water boilers evaluated?

For heating systems, TS EN 12828 and pressure equipment requirements are taken as the basis.

Why is a safety valve important?

It protects the boiler by relieving excess pressure; the opening pressure and capacity must be verified.

What is the duration?

Unless otherwise specified, at least once a year.

Document Your Security

for boiler control Mechanical Equipment Inspections Check out our page; mandatory periodic inspection Check out our guide.