What you need to know about pumps for closed heating and plumbing systems? How does a domestic “wet rotor” circulation pump work? In this review, we will consider the technical characteristics and features of the device of popular models of circulation pumps..
A circulating pump is a device that provides a flow of water under a given pressure in ring or closed systems. It allows you to maintain circulation, and therefore transfer heat in the system..
Circulation pump device
The device is designed for clean water (agent) and usually has a vortex impeller. By their structure, circulation pumps are divided into devices with “wet” and “dry” rotor.
The “wet rotor” is located within the agent environment in a sealed stainless steel chamber that separates it from the dry stator. Such an original solution makes its operation noiseless, and natural cooling (the agent removes the temperature). In addition, the problem of bearing lubrication due to the pumped medium is solved..
Pumps of this structure are very compact, ergonomic and designed for domestic systems. The chamber is usually made of stainless steel, bronze, aluminum (for cold environments) or cast iron (for heating). Impeller – made of technical polymer or stainless steel.
Such design advantages resulted in a relatively low efficiency, which, however, is quite enough for the use of the pump in domestic systems..
Application area:
- Domestic heating and plumbing.
- Increasing the pressure in the water supply system.
- Underfloor heating device from heating pipes.
- Pumping liquids.
Household circulation pumps with a “wet rotor” have the following performance limitations:
- System pressure – up to 10 bar.
- Medium (agent) temperature – up to 110 ° С.
- Head – up to 10 meters *.
- Productivity – up to 10 cubic meters. m / hour.
* – for such pumps, the head is not the height of the water column, but the indicator of overcoming the hydraulic resistance of the entire system.
Parameters of circulation pumps with “wet rotor”:
Parameter Unit Elsotherm ELS 25/8, China “Craton CWP-01”, Russia VORTEX HZ 401-DN 25, Czech Republic Wilo Star-RS 25/4, Germany Grundfos UPS 32-40, Germany Performance l / hour 2400 3000 3500 2500 10000 Head * m 8 4 ten 4 4 Power W one hundred 72 56 48 45 Price (approximate) Rub. 1800 2500 3600 4000 4700
Wilo Star-RS 25/4
“Dry rotor” has a traditional design of an electric motor, which is mated through a shaft with a volute (pump chamber). Seals ensure tightness. In this case, the rotor and stator of the motor interact with maximum efficiency, which affects the increase in efficiency. But at the same time, the open design makes the motor noisy.
Pumps of this design maximize the power of the engine, therefore, their performance is much higher than that of silent household models. Dry rotor principle applied in garden centrifugal and vortex pumps.
