What causes summer cooling tower overflow? How to solve cooling tower overflow?

Cooling Tower Overflow Status and Solutions

For multiple counterflow cooling towers with automatic control, electric valves are used at the cooling tower inlets, but not at the outlets. Under low load conditions, with a single cooling tower operating, less water is circulated, causing the cooling tower sump water level to rise and lead to overflow.

In another scenario, cooling tower overflow can occur when multiple cooling towers of different sizes are connected together; the water levels in the towers vary, and the tower with the lower sump will inevitably overflow.

Cooling Tower Overflow Solutions:

1. Install electric valves at each outlet of the cooling equipment, operating in pairs with the valves at the inlets. When a tower stops operating, simultaneously close the electric valves on the return water pipe to maintain a balanced water level in the sump.

2. Add a pipe to the bottom of the sump of each parallel tower, connecting them via a larger balancing pipe, and increase the diameter of the outlet pipe; this is a simple and effective solution.

The above are just suggestions. Based on experiments, when multiple wastewater cooling towers are operating in parallel, there are generally five piping methods.

Cooling Tower Piping Method 1

Parallel Cooling Tower Piping Layout 2

In our experience, the cooling tower and connecting pipe layout in Figure 2 is the most complex, occupies more space, but has a reasonable flow distribution and high operational reliability. 3. The piping arrangement is simple, but cooling tower overflow and water replenishment frequently occur, mainly due to:

1. Generally, electric valves are installed at the inlet of the cooling tower, not at the outlet. When a cooling tower is not operating, its water valve is closed, but the outlet remains connected. During single-tower operation, the water level in the cooling tower sump rises, leading to overflow, while the sumps of other non-operating towers continuously receive water.

2. Uneven water distribution in each cooling tower is often a problem with the connecting pipes. Some towers have low inlet pipe resistance and high outlet pipe resistance; more water enters than exits, causing overflow. Conversely, some towers continuously receive water.

3. When multiple cooling towers of different sizes are connected, the water levels in the towers vary, and the tower with the lower sump will inevitably overflow.

Based on these issues, the design should consider the balance of cooling towers and pipes, including water level and water volume balance. Generally, for combined water inlet methods, the following countermeasures are adopted:

1. For Figure 1, electric valves are installed at the inlet and outlet of each cooling tower and are interlocked with the water pump and cooling tower fan.

2. For Figures 1, 3, and 4, the water level of each cooling tower (including towers of different sizes) is controlled at the same height, with a maximum height difference of 30mm. Balancing pipes are installed between the cooling towers, and the diameter of the outlet pipes is increased.

3. For Figures 1 and 4, to balance the water volume of each refrigeration unit, balancing valves can be installed at the drain outlet of each refrigeration unit.

With these improvements, previous problems can be effectively solved, and the piping can be completed with simple wiring to facilitate the connection of multiple cooling towers.

During the summer, the cooling tower system operates under high load, and improper line handling will cause the aforementioned problems. Solutions for cooling tower water are key to cooling tower system maintenance. Relevant company personnel should pay attention to any abnormalities in the cooling tower. Cooling tower overflow is a small part of circulating water treatment. If you want to learn more about the basics of cooling tower malfunctions, you can call Guangdong Teling Air Conditioning, a cooling tower manufacturer.