The goal of a fire pump is to increase the water pressure and flow for fire sprinklers, standpipes, and other fire protection systems. Fire pumps are especially important in larger buildings, high-rises, and industrial facilities where the municipal water pressure is not adequate for more rapid and widespread fire suppression applications. Fire pumps use energy to pull water from a water source, such as municipal water supplies, water tanks, or natural water sources. In some occupancies, Early Suppression Fast Response sprinklers are used to suppress the fire at its source. ESFR sprinklers require a high flow rate, necessitating the use of a water pump system and a dedicated water supply.
Sometimes, your systems will require higher water pressures and flow rates than what municipal water supplies can provision. Choosing the right fire pump is essential to achieving optimal performance and preventing damage to your system. In this article, we will explore the different types of fire pumps, their functions, and how to choose the right one for your system.
Fire pumps are generally divided into two categories based on how they generate pressure. The two types are positive displacement pumps and centrifugal pumps. Both types serve different needs and are used in specific application depending on the size and requirements of the fire protection systems.
Positive displacement pumps create high pressure by trapping a fixed volume of water per pump revolution and forcing it out. These pumps are typically used with water mist and foam systems, since it may provide high pressures in waves. While positive displacement pumps are adept at producing high pressures, they have limited flow capacities when compared to centrifugal pumps. For this reason, they are seldom used in large-scale fire protection systems.
Centrifugal pumps are another type of fire pump that is widely used in the fire safety industry. As the name suggests, they use centrifugal, or rotational, force to generate pressure. Subsequently, these pumps can handle large volumes of water while maintaining high pressure. Water enters the pump, is driven to the outside by the spinning impeller, and exits at a higher pressure. This makes centrifugal pumps ideal for fire protection systems that require consistent flow and pressure.
The horizontal split-case fire pump is known for its durability and ease of maintenance. It features a casing that can be split open for quick access to the internal components, making it easy to perform repairs and inspections. These pumps can handle a wide range of flow rates and pressure capacities, and they are typically driven by electric motors or diesel engines. These pumps are more suitable for larger facilities, since they are large and require sufficient space for installation.
Vertical turbine pumps are unique because they can operate with negative suction presssure, allowing them to draw water from sources below grade, such as from rivers, ponds, or underground tanks. This makes them ideal for installations where water is sourced from deeper or more remote locations. Vertical turbine pumps are capable of handling large volumes of water and can be powered by either electric or diesel motors.
In-line fire pumps are compact and designed for installations where space is limited. These pumps are typically powered by electric motors and are used in systems that do not require large flow capacities. The suction and discharge flanges of in-line pumps are aligned on the same plane, making them easy to install in confined spaces. However, maintenance can be more difficult since the motor must be removed to access the pump. Thus, maintenance of the pump is more costly than the easy-to-access split-case units.
End suction pumps are similar in design to in-line pumps, but have a suction and discharge outlet arranged perpendicular to each other. They typically handle capacities up to 1,500 gallons per minute (GPM) and can be powered by either electric or diesel motors. Consequently, they are easy to install and often used in smaller fire protection systems where the available space for installation is a concern.
A diesel and electric fire pump
Multistage multiport pumps are using in large buildings with multiple pressure zones. These pumps use multiple impellers arranged in a series to generate different levels of pressure from a single unit. The pump has several discharge outlets, each delivering water at varying pressures. For example, in a high-rise building, one outlet might supply lower floors with a pressure of 100 psi, while another might supply higher floors with a pressure of 300 psi. As a result, this pump configuration can reduce the need for multiple pumps, saving both space and cost. It can also reduce the need for intermediate water storage tanks, lower structural load, and save on energy consumption.
A jockey pump is a small component designed to maintain pressure in the system’s piping. It helps to prevent pressure drops that could be caused by minor leaks, temperature changes, or trapped air. By running continuously at low flow, the jockey pump ensures the system stays pressurized without engaging the larger fire pump unless there’s a significant demand. It is typically sized to handle less flow than a single sprinkler head, so it only activates the main pump when necessary. Though these pumps are generally small centrifugal units, they do not need to be fire application certified, but their control equipment may need approval. The jockey pump’s pressure is usually set 10 psi higher than the main fire pump to ensure proper system operation.
A fire pump skid is a pre-packaged, self-contained unit that includes all the necessary components for a fire pump system. These units are designed to provide a reliable water supply to sprinkler system, standpipes, or other fire suppression systems. As such, these systems are used when you need to deploy a fire pump quickly and reduce field installation costs.
Choosing the right fire pump is a critical part of designing an effective fire protection system. Fire Pumps ensure that your sprinkler and standpipe systems have the water pressure they need during an emergency. With our extensive experience and commitment to quality, we provide a wide range of fire protection solutions, including fire pump installation, fire alarm system installation and expert guidance.
If you need help selecting or installing a fire pump system, our team of professionals is here to assist you. Contact us today to learn more about how we can support your fire protection needs with the right solutions tailored to your facility.
