FAQs of Manifold Flow Meter

1. What is a Manifold Flow Meter?

It is a flow monitoring device made for sub-water systems and is installed in each branch of floor heating, heating, or similar systems. It measures the flow of water or other fluids in real time. Its main job is to keep the system balanced and show the flow clearly. Common types include float-type and impeller-type flow meters.

2. What is the difference between a manifold flow meter and an ordinary pipeline flow meter?

A manifold flow meter is small and fits the short pipes of a manifold. Its connections match small pipe sizes, like 1/2″ or 3/4″. It shows the flow with a simple float or pointer, so it is easy to read and does not need a complicated setup. A normal pipeline flow meter is bigger, made for large pipes, and used in precise industrial work. It needs more space and careful installation.

3. What is the accuracy of the flow meters produced by the factory?

Float-type flow meters usually have an accuracy of ±5%, which is enough for heating or floor heating systems. Impeller-type meters are more accurate at ±2%, and electromagnetic meters are very precise at ±1%. All flow meters are calibrated at the factory. Customers can also ask for third-party testing and get accuracy test reports if needed.

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4. How to measure the flow rate according to the number of loops of the manifold?

Choosing a flow meter depends on the flow of one circuit, not the total number of circuits. First, find the total flow of the system. Then, divide it by the number of circuits to get the flow for each circuit. Match a flow meter that fits this flow. It is best if the single-circuit flow is 30%–80% of the meter’s range, which makes the measurement more accurate. More circuits mean smaller flow per circuit, so the meter range is smaller and the accuracy is higher.

5. Which type of manifold flowmeter should be preferred for large flow conditions?

For large flows (5 m³/h or more), it is best to use an impeller-type or electromagnetic flow meter. Impeller-type meters with a 1.5″ connection can measure 0.5–8 m³/h, have a simple design, and cost moderately. Electromagnetic meters work well for very large flows of 10 m³/h or more, measure very accurately, do not cause pressure loss, and can connect to a PLC system. They are ideal for industrial use or big building heating systems.

6. Is there a requirement for the installation direction of a manifold flowmeter?

Float-type flowmeter should be installed vertically (fluid flows from bottom to top) to ensure that the float can rise and fall freely, and the installation inclination angle does not exceed 5°; impeller type can be installed horizontally or vertically (fluid from bottom to top when installed vertically); electromagnetic installation direction is not limited, but it is necessary to ensure that the measuring tube is filled with fluid to avoid empty pipe affecting measurement; all types should be kept away from strong magnetic fields and vibration sources.

7. What are the readings of the flowmeter?

There are three main types of flow meters:

① Mechanical float display, the most common type, shows the flow by the float moving inside a transparent tube. And you can read the value directly in m³/h without needing power.

② Pointer display, where an impeller moves a pointer on a scale, giving higher accuracy than float types.

③ Digital display, a smart model with an LCD screen that shows real-time flow and total flow. It can switch units (m³/h or L/min), works on battery or external power, and some models can send data wirelessly.

8. How to avoid damage to the connector threads of the manifold?

Before taking the manifold apart, first close the main valve and the valve of the loop you will work on. Then open the exhaust valve to let out the pressure and make sure the pipe has no pressure inside. This helps avoid accidents like tools slipping because of fluid. Use the right pipe wrench or tongs, and wrap the jaws with a soft cloth so the metal tools do not directly touch and damage the pipes.

9. Can the flow meter provide rework services?

To allow the flowmeter to be reworked for a different range, two things must be true:

First, the flowmeter has not been installed or used, so it has no damage or worn threads; Second, the new range must fit within the adjustable limits for that model. For example, a flowmeter with a 1/2″ interface can be changed within 0.05–1.5 m³/h. If the desired range is higher, the core part must be replaced.

10. Is there any length requirement for the front and rear straight pipe sections during installation?

The floating ball type has no strict requirements for the straight pipe section. It is recommended to reserve ≥ 50mm straight pipe section before and after installation point to avoid flow field disorder caused by direct connection of elbow; impeller type is recommended to reserve ≥ 100mm straight pipe section before and after; electromagnetic type is recommended to reserve ≥5 times pipe diameter at the front and ≥3 times pipe diameter at the back to ensure measurement accuracy.