Every structure, even the most modern one, can fail and begin to operate incorrectly. Problems related to operation in the broadest sense also affect heating systems that use circulation pumps. Sometimes, worrying symptoms are visible at first glance, allowing us to take quick preventive and corrective action. What symptoms are we talking about? Which signs should receive particular attention? What should concern us? And what are the most common causes of a circulation pump malfunction? We answer these and other questions in our article.
Worrying symptoms—what should you look out for?
Incorrect operation of a circulation pump can be associated with numerous symptoms. Above all, we should pay attention to unusual noises, such as sounds resembling hammering, which are usually caused by pressure surges and mass inertia. A general increase in the noise level produced by the circulation pump may also be a cause for concern.
Another symptom is excessive heating of the circulation pump, particularly its motor, as well as insufficient cooling of the key components of the entire system. Other worrying symptoms include an overall deterioration in system performance, increased electricity consumption, underheated rooms—especially when temperatures outside are below freezing—emergency pump shutdowns, and complete failure of the heating appliance.
Incorrect circulation pump operation—the most common causes
There can be many causes of incorrect circulation pump operation. One of them is overheating caused by:
- voltage that is too low or too high,
- instability of the three-phase current,
- deterioration of insulation resistance,
- high ambient temperature,
- lack of ventilation,
- excessive speed,
- flow rates that are too low or too high,
- increased friction in a mechanically damaged pump,
- high fluid viscosity or excessive fluid density.
Incorrect connections between individual pump components, particularly its sensors, should also be taken into account. The most common causes of failure also include a broken or loose impeller, a damaged bearing or seal, damage to the drive wheel, and a narrowed cross-section caused by corrosion or sealant.
Other causes include:
- a damaged drive wheel or a loose drive-wheel ring: excessive timing-belt tension, incorrect belt positioning, or a cracked water-pump bearing (bearing cage),
- coolant leakage caused by applying too much sealant,
- corrosion throughout the cooling system, particularly damage to the cylinder-head gasket,
- serious damage to pump components, such as the impeller or housing,
- excessive coolant leakage from the drain hole caused by corrosion in the cooling system.
