Hot Water Flow Meters

Hot Water Flow Meters Improve Heating-Boiler System

Hot water flow meters refer to flow meters that can measure and indicate the flow of high temperature water. Hot water is widely used in industry and civil use. Such as heating systems, baths, boilers, industrial indirect heating, heat transfer, etc. There are many types of water flow meters. Some of the most common types include electromagnetic flow meters, turbine flow meters, and vortex flow meters. These meter types have unique features that distinguish them from each other. According to the function of the hot water flow transmitter and the user’s budget. You can choose a suitable flow meter to monitor the hot water pipeline.

Hot Water Flow Meters

Features of Hot Water Flow Measurement

What are the characteristics of hot water flow measurement? Let’s take a look.

  1. The temperature of the measured fluid is not very high. When the flow meter is installed at the entrance of the heat exchanger body. The temperature of the fluid is generally not higher than 140°C. When the liquid outlet of the heat exchanger is installed, the flow temperature is lower.
  2. The measured fluid pressure is not very good either. In order to send hot water to the highest floor in the building heating system, the pressure is sometimes higher. In the ground heating system, the highest pressure is 1MPa.
  3. The pipe diameters vary in size. The smallest user, the pipe diameter is only DN20~DN40. The large-diameter flowmeter sometimes reaches about 1m.
  4. Better cleanliness. Hot water is not as clean as tap water. The solid matter in the single water and its viscosity will not have a big impact on the general flowmeter.
  5. Corrosive. Fresh water does not corrode the flowmeter. However, geothermal water has a certain degree of corrosion. Because it contains chloride ions and so on. Ordinary stainless steel materials are corroded, and the higher the fluid temperature, the more severe the corrosion.
  6. The requirement for scope is not high. The pumps used in power plants (stations) to deliver hot water are generally combined in size. When the hot water supply is at its maximum, usually several large pumps are opened. When the heat supply is the smallest, generally only a small pump is turned on. The ratio of the maximum flow rate to the minimum flow rate is about 5~10. A flow meter for heat measurement of a single user. In the heating season, the flow measurement range of up to 10 can meet the demand. After the hot water valve is turned off, the market value of the flow should be 0.

Extended Reading: Insertion Flowmeter Types

Hot Water Flow Meter Types

Hot water is the most widely used heat carrier liquid. Due to the difference in use and design, the water supply temperature is commonly used in several grades such as 60℃, 90℃, and 130℃. There are fresh water and geothermal water in the varieties of water. The temperature of geothermal water cannot be determined independently, but it must be above 60°C to have use-value. Flow Meter Selection Guide 101: Find the Perfect Fit for Your Application

Magnetic Water Flow Meter provide highly accurate flow measurements for a wide variety of conductive fluid applications. Magnetic Water Flow Meter is a volumetric flow meter that measures liquids or liquid slurries that have a minimum conductivity of 5 µS/cm.

An electromagnetic flowmeter is an ideal instrument for hot water flow measurement. Its significant advantages are as follows.

  • The pressure loss is negligible. Because the inner diameter of the measuring pipe is the same as that of the pipe.
  • From small to large caliber, the series is complete.
  • The measurement accuracy is high, and the high accuracy can still be achieved when the flow rate is very low.
  • The temperature grade can meet the needs. Among them, the temperature resistance rating of 120°C can meet the measurement needs of most objects. The temperature resistance rating of 180°C can meet the needs of measurement objects with fluid temperatures higher than 120°C.
  • The pressure level can meet the measurement needs. In the electromagnetic flowmeter product sample, the pressure level of the finalized large-caliber electromagnetic flowmeter can only reach 0.6-1MPa. But it can be used as a special order to meet the requirements of objects with higher pressure.
  • Corrosive series products. Geothermal hot water has different corrosive properties due to different production areas. For geothermal hot water containing chloride ions, electromagnetic flowmeters with PTFE lining and titanium electrodes have met the needs.
  • Strong adaptability to the vibration of the pipeline and the environment.
  • It can measure pulsating flow with low pulsating frequency.

Extended reading: 2 inch Water Flow Meter

The turbine flow meter for hot water can measure soft water, soft water and RO water. These are the main water types best suited for turbine flow meters. The maximum hot water temperature of the turbine flowmeter is 150 degrees Celsius.

Turbine flowmeters are based on the principle of torque balance and belong to velocity flow meters. It is widely used in petroleum, chemical, metallurgy, water supply, papermaking and other industries. It is an ideal instrument for flow measurement and energy saving.

  • The function of the turbine flowmeter as a hot water flow meter:
  • High accuracy. Generally up to ±1%R, ±0.5%R, high-precision type up to ±0.2%R;
  • The repeatability is good, and the short-term repeatability can reach 0.05%~0.2%. It is because of the good repeatability, such as frequent calibration or online calibration can get extremely high accuracy. It is the preferred flowmeter in trade settlement;
  • Output pulse frequency signal. Suitable for total measurement and connection with computer. No zero drift, strong anti-interference ability;
  • High frequency signals (3-4kHz) can be obtained. Strong signal resolution;
  • Wide range, medium and large diameters can reach 1:20, and small diameters are 1:10;
  • The structure is compact and light. It is convenient to install and maintain, and has a large circulation capacity;
  • Suitable for high-pressure measurement. No holes are required on the meter body, so it is easy to make a high-pressure meter;
  • There are many types of sensors. Various types of sensors can be designed according to the special needs of users, such as low temperature type, two-way type, downhole type, sand mixing type, etc.;
  • It can be made into a plug-in type, suitable for large-caliber measurement. The pressure loss is small, and the price is low.

Extended Reading: Metal Tube Flow Meter Applications

Use a vortex flowmeter to measure hot water. The pipe diameter of the boiler feed water is below 300mm, which is exactly the pipe diameter range of the full-tube vortex flowmeter.
Different from measuring steam, when measuring hot water, the installation of vortex flowmeter should ensure that the pipe is full and there is no air. The horizontal installation is suitable for the lowest point. When vertical installation, the hot water should flow from bottom to top. Inaccurate.

  • Features of measuring hot water flow with vortex flowmeter:
  • The temperature of the hot water is not very high, and the maximum temperature does not exceed 140 ℃;
  • The cleanliness of hot water is relatively high, and the water does not contain solid matter;
  • The water contains chloride ions, which is corrosive to ordinary steel. And as the water temperature rises, the corrosiveness increases;
  • The maximum pressure of hot water used in the heating system is 1MPa. The pressure used for water is higher, about several megapascals;
  • The pipe diameters vary. The pipe diameter of the boiler water supply pipe is 50~300mm. The pipe diameter of the heating system is quite different. The smallest pipe diameter is 20-40mm, and the largest pipe diameter can reach 1000mm.
  • The flow range ratio is about 5:1~10:1.

The adaptability of ultrasonic flowmeter is incomparable to other types of testing instruments. It has been made into a basic type, high temperature type, explosion-proof type, and wet test type instrument panel with different sound channels to incorporate different substances, different places and different Pipeline standard flow measurement.

Extended reading: non contact flow meter

Ultrasonic flowmeters mainly have the following advantages in practical application:

  • Ultrasonic flow meters are more convenient and faster to install and maintain in practice.
  • The measuring pipe diameter of the ultrasonic flowmeter is relatively large.
  • The measurement reliability of the ultrasonic flowmeter is high.
  • The measurement of ultrasonic flowmeter will not be affected by fluid-related parameters
  • It can be used as a clamp-on ultrasonic flowmeter, which is quick and easy to install and use.
  • It can measure heat and flow at the same time.

Extended reading: Industrial VS Residential inline water flow meters

On the large-diameter pipes of the power plant (station), the orifice plate is still used to measure the flow of water supply and the amount of return water.

Mainly take the following advantages:

  1. The orifice itself has high reliability. The heating will not be interrupted due to the orifice plate.
  2. Convenient verification. The orifice plate only needs to be verified by geometric method. It is not necessary to send the verification center to the standard device for real flow calibration like some flow sensors and transmitters.
  3. When the caliber is large, the investment is relatively low.

Its biggest shortcoming is the large pressure loss, which is not conducive to saving power.

Extended reading: Insertion Ultrasonic Water Flow Meter – Designed for Agricultural Irrigation, Garden Management

Extended Reading: Chilled Water Flow Meter

Hot Water Flow Meter Specifications

Hot water flow meterPipe diameter rangeAmbient temperatureMedium temperatureReference accuracy
Magnetic flow meterDN15~DN3000-25ºC~+60ºC -25℃~+150℃±1.0%
Turbine flow meterDN4~DN200 -10~+55℃ (-196~80)℃
-20~+80℃;-20~+120℃; -20~+150℃;
 ±0.5%, ±1%
Vortex flow meter DN15~DN300
-35℃~+60℃ Piezoelectric type :-40~150,-40~260,-40~330℃;
Projected Capacitive:-40~400℃ (Consulting supply)
Ultrasonic flow meter DN15~DN6000-20ºC~+60ºC -40℃~+160℃ ±1% 

Extended reading: Quantitative control with turbine flowmeter

Hot Water Flow Meter with Pulse Output

Commonly used flow meters have three forms: current output, voltage output, and pulse output.

Among them, the current output and the voltage output signal of the instrument are in line with the International Electrotechnical Commission (IEC) standard. There is currently no standard for the pulse output signal of the instrument.

The flowmeter with pulse output, its output is a pulse signal proportional to the flow rate. Compared with the analog signal of voltage and current, the pulse signal is convenient for remote transmission without reducing the accuracy, and there is no zero drift. It is easy to connect with the computer, easy to carry out cumulative display and has a strong anti-interference ability.

Extended reading: Ultrasonic Water Meter for Residential Water

Water Flow Meter Types

There are many types of flow meters for measuring water.

Common ones are V cone flowmeter, electromagnetic flowmeter, metal rotor flowmeter, vortex flowmeter, liquid turbine flowmeter, ultrasonic open channel flowmeter, ultrasonic flowmeter, etc.

At present, electromagnetic flowmeters and turbine/vortex can solve most of the working conditions.

More about:

Featured Digital Water Flow Meter

Extended Reading: Inline Ultrasonic Flow Meter

Hot Water Flow Meter Price

Sino-Inst offers over 30 water flow meter products. About 50% of these are differential pressure flow meters. 40% are water meters (like the Insertion Turbine Flow Meter), and 40% are water treatment (like the Annubar flow meter ).

A wide variety of water flow meter options are available to you, such as free samples, paid samples.

Sino-Inst is a globally recognized supplier and manufacturer of water flow meters, located in China.

The top supplying country is China (Mainland), which supply 100% of the water flow meter respectively.

You can ensure product safety by selecting from certified suppliers, with ISO9001, ISO14001 certification.

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About KimGuo11

Wu Peng, born in 1980, is a highly respected and accomplished male engineer with extensive experience in the field of automation. With over 20 years of industry experience, Wu has made significant contributions to both academia and engineering projects. Throughout his career, Wu Peng has participated in numerous national and international engineering projects. Some of his most notable projects include the development of an intelligent control system for oil refineries, the design of a cutting-edge distributed control system for petrochemical plants, and the optimization of control algorithms for natural gas pipelines.