Plate heat exchanger unit
The plate heat exchanger unit automatically converts the heat obtained from the primary network into the domestic water and heating water required by the user. That is, the hot water (or steam) enters the plate heat exchanger from the primary side inlet of the unit for heat exchange, and then flows out from the primary side outlet of the unit; the secondary side return water passes through the filter to remove the dirt, and then enters the plate through the secondary side circulating water pump. The heat exchanger performs heat exchange to produce hot water for different temperatures such as heating, air conditioning or floor heating to meet the requirements of users.
Heat exchanger unit function: (can be selected according to user needs)
1. Temperature regulation control: The circulating water flow rate is constant, and the heating temperature is automatically adjusted according to the ambient temperature change, so that the heat supply is matched with the system load to achieve the purpose of saving heat energy.
2. Flow regulation control: The heating temperature is constant, and the circulating water flow is automatically adjusted according to the environmental temperature change and the supply and return water pressure difference, so that the heat supply is matched with the system load to save energy.
3. Water pressure control: The pressure sensor automatically starts, stops the water pump or adjusts the speed of the water pump according to the measured system pressure according to the measured pressure of the return water to stabilize the system pressure, ensure the safety of heat, and maintain the normal operation of the system. The pressure control range is determined according to design requirements.
4. Condensate recovery control: The liquid level controller automatically turns on and off the condensate pump according to the change of the liquid level of the water tank, and automatically sends the condensed water back to the boiler room for recycling, reducing the waste of softened water and heat. The condensed water level control range is shipped from the factory. confirmed.
Features of the heat exchanger unit:
1, Intelligent control, complete control functions, high control precision, stable and reliable operation.
2, The unit adjusts the heat source and hot water supply according to the ambient temperature, primary and secondary pipe network temperature, pressure and other parameters, and has obvious saving effect on heat energy and electric energy during system operation.
3, The system components are highly reliable, and the heat exchanger is a high-efficiency plate heat exchanger. The main intelligent components are imported, which is stable and reliable in operation and durable.
4, system pressure, temperature into the flow automatic control, intelligent, high degree of automation, easy to operate.
5, can be remotely monitored, can also be switched between manual and automatic.
6, Unattended units can realize on-site personnel without duty and direct monitoring by remote.
7, The unit layout is reasonable, the structure is compact, the floor space is small, the capital construction investment is saved, the installation and maintenance are convenient, and it is suitable for various heating places and heating requirements.
Commonly used control strategies:
(1) The heat exchanger unit has climate compensation and horizontal grain water supply function
The programmable controller automatically sets the two-side water supply temperature according to the change of the outdoor temperature and the local heat load curve, and can set the compensation amount according to the requirements. The measured value of the secondary side water supply temperature is compared with the set value, and is adjusted by PID. The controller output signal adjusts the electric valve for temperature control.
(2) Automatic hydration
The pressure sensor installed on the secondary side return pipe measures the pressure signal, and outputs a control command after comparing with the set value to control the start/stop of the make-up water pump or the constant pressure water supply by the variable frequency.
(3) Automatic pressure relief function
The unit can choose the hot water expansion overpressure in the pressure expansion tank buffer system; it can also use the electromagnetic valve to relieve pressure; to ensure absolute safety, the safety valve is configured in both ways.
(4) Secondary side supply
The return water pressure difference control supply, the water return system needs to set the differential pressure bypass valve, usually installed between the water separator and the water collector, or can be arranged in the heat exchange unit. Purpose: When the load becomes smaller, the return pressure will become lower, and the circulating pump will be in a low-flow working state. Frequent changes in the load will cause the pump to change continuously, affecting the life of the pump. At this time, the pressure difference in parallel with the load The bypass valve is opened to ensure the water circulation of the system; on the other hand, the addition does not control the pressure difference between the supply and return water, the water preferentially returns from the near-end user, and the near-end user does not get enough when the near-end user works under heavy load. flow. In the state of the differential pressure bypass valve, most users still choose the variable frequency circulation valve to increase the stability of the system. The pressure difference can be set on the field controller or remotely.
(5) Power failure protection function
When a sudden power failure occurs, the electric valve on the primary side will automatically turn off the heat source (such as steam) to prevent the secondary side from overheating or even vaporization, destroying the heat exchanger and the pipeline, and the controller and inverter automatically reset and make various settings. The parameters and operating parameters are maintained before the power is turned off.
(6) Power-on self-test function
The secondary return water pressure has a set of ultra-bottom line protection paper. When the secondary side pressure does not reach this value, the circulation pump cannot be started and only the make-up water pump can be turned on to replenish water. When the set value is reached, the circulation pump can be started. After the unit is powered, the self-test sequence starts each unit.
(7) Loss of pressure protection
When the secondary side return water pressure is lower than the set value, the circulation pump operation is automatically stopped.
(8) Over temperature protection
When the temperature of the primary side heat source exceeds 180 degrees, the electric valve is automatically closed and an alarm signal is provided.
(9) Overpressure protection
After the secondary water supply pressure exceeds the set value, the primary side electric valve is closed except for the automatic pressure relief.
(10) Monitor the tank level
When the tank level is lower than the ultra-low line, the make-up pump stops and provides an alarm signal.
(11) Time control program
It can be timed on and off, energy-saving mode, and set time-to-time heating for day, week and month.
Specialized system design.
The compact design saves floor space and capital costs.
Intelligent design of human-machine interface unattended, remote monitoring.
Rich operational experience.
The selection of reliable components.
Professional and reliable service team, quick response and lifetime warranty.
Professional training allows the operator to be proficient in control.
Capacity range: 0.1m3/h to 2500m3/h
Operating pressure: ≤2.5MpaG
Operating temperature: ≤150°C
Plate material: stainless steel 304, 316L, carbon steel.