Heat Exchanger Unit Commissioning

◎Preparation

1. First, check that the heat exchanger components are intact and that the valves and control cabinet are powered off.

2. Manually rotate the pump motor blades. The impeller should rotate freely and without any signs of sticking.

3. Open the pump inlet valve and the exhaust valve to allow the liquid to fill the entire pump chamber. Then close the exhaust valve.

4. Manually rotate the pump to allow lubricant to enter the mechanical seal.

◎Preparation

5. Turn the power on and jog the motor to ensure the pump is rotating in the forward direction.

6. Determine the opening pressure of the safety valve based on the set pressure and adjust the pressure accordingly. The set pressure is generally 1.1 times the set pressure.

◎ Commissioning

1. Turn the control cabinet switch to "Manual," press the pump start button, and gradually open the pump outlet valve. Check to see if the starting current exceeds the rated value. Observe for any abnormalities and check for shaft seal leakage. If any abnormality is detected, shut down the pump immediately and address it.

2. Commission each pump according to step 1.

3. Commission the thermostatic valve according to the thermostatic valve manufacturer's instructions and check that the temperature controller settings are correct.

◎ Commissioning

4. When the secondary system pressure stabilizes, open the primary outlet valve and then slowly open the primary inlet valve. During the circulation process, the secondary side temperature will gradually increase until the secondary water outlet temperature reaches the set point. The secondary side temperature should not increase too quickly to prevent rapid expansion of the secondary system and a shock to the system.

5. Observe the circulating water system flow, pressure, temperature, and pump operation for normal operation.

◎Operation

1. During normal operation, first power off the control cabinet and start the make-up water pump. After the secondary pressure reaches the set pressure, switch the make-up water pump to automatic operation. Start the circulation pump. After the secondary circulating water pressure stabilizes, open the primary inlet valve to heat the circulating water in the system to the set temperature.

2. If the temperature rises or falls below the set value, if a temperature control system is installed, the temperature sensor transmits a signal to the temperature control system, which automatically adjusts the valve opening to change the heat source flow rate. If a temperature control system is not installed, the on-duty personnel manually adjust the primary inlet or outlet valve opening to change the heat source flow rate.

3. Once the heating and heat exchanger unit is operating stably, dedicated operation is generally not required. However, data such as temperature, pressure, and flow rate at various points should be recorded every 2-6 hours to ensure that the heat exchanger is operating within normal range. Also, pay attention to the operating status of the water pump. Pay particular attention to whether the secondary system pressure is too low to prevent excessive water loss and untimely water replenishment, which could cause the circulating water pump to operate in a water-starved state and burn out.