What Is a Hot Water Recirculating Pump?

How often do you receive complaints about slow hot water or are frustrated by your building’s water and energy costs? With New York City’s focus on efficiency, most property owners are trying to find ways to accommodate changing regulatory demands without sacrificing tenant comfort or increasing operational costs. Thankfully, one plumbing installation can help. What is a hot water recirculating pump, and how can it help with tenant complaints, building appeal, and operational costs?

What Is a Hot Water Recirculating Pump?

Basic Components and Function

A hot water recirculating pump is a small but powerful device. It is usually installed near the water heater and continuously circulates hot water through your pipes, eliminating wasted water.

The pump draws slightly cooled water from the farthest point in your hot water line, pulling it back towards the water heater. Depending on the system, the water returns to the heater through a dedicated return line or a cold water line. Hot water then replaces the cold water, ensuring a continuous and reliable flow of on-demand hot water.

Purpose of the System

A hot water recirculating pump provides a constant flow of hot water in your system, allowing instantaneous hot water from any fixture at any time. Without a pump, the water in your building’s hot water lines gradually cools as it sits unused. Every time you, a tenant, or a staff member turns on a hot water tap, the cool water gets expelled as hot water rushes to replenish the lines, meaning wasted water. The pump eliminates the waste or at least reduces it, allowing for a more efficient system.

How Do Traditional Hot Water Systems Work?

The Problem of Wasted Water

A hot water recirculating pump solves a typical plumbing problem: wasted water. Tank-styled water heaters store a set volume of water, constantly heating it to a predetermined temperature. Insulated hot water pipes branch out from the heater, delivering hot water throughout the building or unit. When a faucet opens, it draws hot water from the pipes, allowing cold water to replace it at the bottom of the water heater, where it starts the cycle all over again.

Unfortunately, distance and time matters. The farther a faucet is from the water heater, the greater the opportunity for heat loss. Also, the longer the hot water sits in the line, the more it cools. Every time a hot water tap opens, the cooled water must vacate the line to make room for the fresh hot water, resulting in wasted water.

Also, traditional systems cannot differentiate between actively used periods and low-demand times, meaning they provide constant and often unnecessary heating. Your building’s water heater works harder than necessary, resulting in premature wear.

How Do Recirculating Pumps Improve the Situation?

Constant Flow of Hot Water

A hot water recirculating pump is a device that creates a continuous, gentle flow of water through the hot water lines. This process ensures the water furthest from the water heater cycles back through the system to maintain a consistent temperature throughout.

Because of the constant flow of hot water, tenants have instantaneous access to hot water at any tap in the building. The pump eliminates the risk of heat loss and standby cooling, ensuring tenants the reliability of fresh hot water without waiting.

Water Conservation

Traditional systems lead to a significant amount of water going down the drain while tenants wait for the hot water. A recirculating pump can eliminate most of that waste because it ensures hot water flows through the system and is ready for use.

Depending on the complexity of your plumbing system and the length of the hot water lines, a recirculating pump can save a surprising amount of water over a day, month, or year. Still, water conservation is not the only benefit of the system in terms of efficiency.

Increased Energy Savings

Ultimately, a hot water recirculating pump is a tool that increases energy savings and improves system efficiency. The primary benefit of the pump is its ability to reduce or near-eliminate standby heat losses. By circulating the water, the pump reduces heat loss and makes the water heater more efficient.

The device also prevents unnecessary heating cycles. With the constant flow of water in and out of the heater, the system can more accurately “sense” when hot water or reheating is necessary. The continuous cycling or flow ensures the water heater isn’t constantly reheating the entire tank volume.

Overall, the combined effect of reduced standby loss and prevention of unnecessary heating contributes to a notable reduction in energy use. A recirculating pump should lower utility bills over time, especially if tenants and staff use water responsibly.

What Types of Hot Water Recirculating Pumps Are Available?

Dedicated Return Line Systems

The hot water recirculating pump can attach to two types of systems. The first is the dedicated return line system, which uses a return line that runs parallel to the hot water lines, connecting to the farthest point in the system. The pump attaches to the dedicated return that carries cooled water back to the water heater.

Dedicated return line systems provide maximum efficiency and ensure readily available hot water. They are closed-loop systems often used in properties with more complex plumbing layouts.

Return Line-Free Systems

In a return line-free or point-of-use system, a hot water recirculating pump is closer to the fixture than the water heater. For example, a pump may be installed directly under the sink or fixture farthest from the water heater. These systems use an existing cold water line rather than a dedicated line as the return path.

When activated, the pump pulls cooled water from the hot water line and pushes it into the cold water line, which travels back to the water heater. While typically less expensive, the point-of-use setup is not an ideal solution for a multi-unit property.