The Chiller system is an air conditioner that generates a cold source to cool objects and food, is a chiller used in the central air conditioning system, using water as a refrigerant. Water will be cooled through an evaporator (usually at 12oC and out to 7oC).
The Chiller system is composed of many components, in which the water pump plays a very important role. In the chiller system, there are 2 main types of pumps:
- Cold water supply pump: is the pump that supplies water to equipment such as AHU, PAU, FCU ...
- Cooling water supply pump: is a water supply pump to a cooling tower.
In this article, we would like to share with you the basic criteria when choosing Pumps for water cooled Chiller systems:
- Determine the flow, head of the chiller pump:
- The calculation of the chiller pump flow is as follows:
Based on the cooling capacity, cooling of the equipment and the temperature difference between the return line and the feed line to calculate. Specifically, the formula for calculating pump flow in a chiller system is as follows:
G = Q / (Cp x (∆T)
Inside :
G: Pump water flow rate (l / s)
Q: Cooling capacity or cooling capacity (kw)
Cp: Specific heat of water (4.18 kJ kg – 1 K – 1)
∆T: The temperature difference between the feed / return water
For example: If the cooling capacity of the chiller is 3000kw, the water temperature in the system is 7 and 12 degrees C then: G = 3000 / (4.18 × 5) = 144 (l / s)
- How to calculate head of pump Chiller:
After calculating the flow rate, we calculate the head to choose the pump. The formula for calculating the head of a chiller pump is as follows:
H= (H1+H2+H3+H4)x(1.15-1.2)
Inside :
H: The pump head needs to be calculated, usually taking the farthest and highest segment (mH2o unit)
H1: Height of open water surface. The closed circuit should be H1 = 0
H2: Pressure at the final outlet of the device. Closed circuit so H2 = 0
H3: Friction loss between water and pipe
H4: Friction loss through equipment such as evaporator, condenser, AHU, FCU, PAU ...
1.15 -1.2: factor of safety, also known as the backup factor. Take 15 or 20% depending on the project.
- Determine the working pressure of the pump:
Chiller air conditioning system is a closed circulatory system. Therefore, when choosing a pump for a Chiller system, it is necessary to pay attention to the pressure in this system.
- Determine the rotation speed of the pump motor:
Pumps for Chiller air conditioning systems usually operate regularly for a long time, so it is necessary to choose a pump with a low speed of rotation to reduce the noise of the pump, increase the life of the pump, normally choose a pump with a rotation speed. 1450rpm, 1000rpm, ...
- Pump performance:
Pump performance is inversely proportional to the capacity of the pump. The higher the efficiency of the pump, the lower the capacity, and vice versa. Therefore, when choosing a pump for the Chiller air conditioning system, it is necessary to carefully calculate to choose the pump with the highest efficiency in order to save energy and protect the environment.
- Pump performance:
According to the current international energy saving standards, the criteria for evaluating the working efficiency coefficient of electric motors (IE) are more interested by the investors to minimize the operating costs of the following system. this. These indicators are prioritized by investors for the current selection of pumps for Chiller air conditioning systems such as IE3, IE4,….
- Choose the right pump type:
Pumps for Chiller systems usually use the following types:
- End Suction type horizontal centrifugal pump
- Split case horizontal centrifugal pump
- Single cascade centrifugal pump
Depending on the design, installation site and some other criteria, choose the pump that best suits your needs.
The technical parameters needed when choosing a pump, see more at the link: Lesson 1CARE SPECIFICATIONS TO CHOOSE INDUSTRIAL PUMPDOCX
After evaluating the above criteria, we have basically selected the type of pump that matches the specifications of the required system. In addition, to evaluate the "soft" plus for these criteria, we also need to consider the pump brand and the supplier's capacity because the Pump for Chiller System is a type of computer. high tech. In order to increase the efficiency and service life of the pump, we need to select a supplier with experience and good technical service capability to assist with related issues.
Dai Nam technician inspects the pump for the Chiller system at the State Audit Headquarters project 2
DAI NAM Company with more than 15 years of experience in the field of supplying Industrial Pumps, is the General Distributor of Pumps brand MASFLO - France in Vietnam. The pump brand MASFLO / France has been used by reputable investors with a variety of types for water supply and drainage systems, fire protection and Chiller systems. The product has good quality and after-sales service, in accordance with the requirements of current projects and meets high international standards such as NFPA20, UL Listed, DIN, EN,… standards.
For more information please contact:
DAI NAM SCIENCE INDUSTRIAL JOINT STOCK COMPANY
Address: Room 303- 3rd floor, AN BINH mixed building 1- Number 3 Tran Nguyen Dan street-Dinh Cong new urban area- Dinh Cong ward - Hoang Mai district - Hanoi.
Hotline: 0383 478 272 Tel: 024 364 00111
Email: dainam@dainamco.vn Website: congnghiepdainam.com.vn
