Commercial boilers do great work heating buildings, but occasionally they have problems.

Here’s a look at some situations you may encounter:

• If the boiler shuts off automatically or won’t start, the trouble may be a valve blockage, a damaged pump, low air pressure or a defective thermostat.

• There could be several reasons why a boiler produces little or no heat. Dust and dirt may be blocking the burners, or there could be a malfunction with the ignition, thermostat or pump.

• When the boiler makes “kettling” noises or other unusual sounds, it is telling you that problems are imminent. Limescale may be built up or the water pressure may be low, or the system is leaking or overheating. (Kettling gets its name because it resembles the sound of a kettle getting warm.)

• A leak can be due to a damaged component, condensation, a weakened pressure valve or corrosion.

• Leakage can cause low steam pressure, which is a serious problem because it makes water pressure and heat distribution drop sharply.

Premier HVAC services and installs commercial boilers in Brooklyn, Queens, Manhattan and Long Island.